Vulnerability database
Every flaw the U.S. government’s cybersecurity agency (CISA) has confirmed attackers are using, plus the new WordPress plugin and theme bugs published each day, sorted by what they mean for a small business. We refresh it twice a day. If you see something your website or office runs, tell us.
25 results
Oct 21, 2026Jupyter Server is the backend for Jupyter web applications.CVE-2026-114135 · Other software · jupyter-server · reported by GitHubHigh 8.8
Jupyter Server is the backend for Jupyter web applications. From 2.0.0 until 2.6.0, enabling GatewayClient.url replaced the normal KernelWebsocketHandler with WebSocketChannelsHandler, which authenticated the user but did not call authorizer.is_authorized(...) for the execute action on the kernels resource. A restricted authenticated user could therefore open an upstream kernel channel and obtain kernel execution despite the configured Authorizer denying that action, exposing data and credentials available to the kernel and permitting modification or disruption of the kernel environment. The default gateway configuration is fixed in version 2.6.0. In 2.6.0 and later, the same authorization bypass remains possible when a deployment manually registers the deprecated jupyter_server.gateway.handlers module, because its handler still omits the configured kernel-execute authorization decision.
- Product
- jupyter_server
- What to do
- Apply the vendor’s update. The NVD record links to the advisory.
Sep 17, 2026Jupyter Server is the backend for Jupyter web applications.CVE-2026-86049 · Other software · jupyter-server · reported by GitHubHigh 7.1
Jupyter Server is the backend for Jupyter web applications. Prior to version 2.21.0, the 5xx request logging path in jupyter_server/log.py copies the Referer header into a JSON header block without applying the token scrubbing used for the request URI. A request that returns HTTP 500 while the Referer contains a token-bearing URL can therefore write that token to server logs in plaintext. An attacker who can read those logs can recover the token and use the affected user's Jupyter Server permissions. This issue is fixed in version 2.21.0.
- Product
- jupyter_server
- What to do
- Apply the vendor’s update. The NVD record links to the advisory.
Jul 16, 2026Jupyter Enterprise Gateway launches remote Jupyter Notebook kernels across distributed clusters like Apache Spark, Kubernetes, and Docker Swarm.CVE-2026-44182 · Other software · jupyter-server · reported by GitHubCritical 10
Jupyter Enterprise Gateway launches remote Jupyter Notebook kernels across distributed clusters like Apache Spark, Kubernetes, and Docker Swarm. In versions prior to 3.3.0, the server interpolates untrusted environment variables (e.g., KERNEL_XXX) into Kubernetes manifests without YAML-aware escaping, enabling YAML injection attacks. Attackers can inject new fields, overwrite critical fields (e.g., duplicate securityContext keys, where the last one prevails), and inject document boundaries (--- for new documents, ... for end-of-document) to generate multiple resources, potentially creating arbitrary types, such as privileged pods. The Jinja2 template for the Kubernetes manifest contains several kernel_xxx variables, such as kernel_working_dir that are used when rendering the manifest and are all vectors for YAML injection. This issue has been fixed in version 3.3.0.
- Product
- enterprise_gateway
- What to do
- Apply the vendor’s update. The NVD record links to the advisory.
Jul 16, 2026Jupyter Enterprise Gateway launches remote Jupyter Notebook kernels across distributed clusters like Apache Spark, Kubernetes, and Docker Swarm.CVE-2026-44181 · Other software · jupyter-server · reported by GitHubCritical 10
Jupyter Enterprise Gateway launches remote Jupyter Notebook kernels across distributed clusters like Apache Spark, Kubernetes, and Docker Swarm. In versions 2.0.0rc2 and above, prior to 3.3.0, the environment variables (KERNEL_XXX) used during the rendering of the Kubernetes manifest are vulnerable to Server Side Template Injection (SSTI). By including Jinja2 template expressions it is possible to execution Python code and OS Commands in the Enterprise Gateway service. The code can use or steal the Kubernetes service account token, which can steal Kubernetes secrets and be used to fully compromise the Kubernetes cluster by scheduling a privileged pod or a pod with a hostPath volume mount. This issue has been fixed in version 3.3.0.
- Product
- enterprise_gateway
- What to do
- Apply the vendor’s update. The NVD record links to the advisory.
Jul 16, 2026Jupyter Enterprise Gateway launches remote Jupyter Notebook kernels across distributed clusters like Apache Spark, Kubernetes, and Docker Swarm.CVE-2026-44180 · Other software · jupyter-server · reported by GitHubCritical 9.8
Jupyter Enterprise Gateway launches remote Jupyter Notebook kernels across distributed clusters like Apache Spark, Kubernetes, and Docker Swarm. Versions 2.0.0rc1 and above prior to 3.3.0 have a prohibited UID and GID feature that by default prevents launching kernels with UID or GID 0 (root), and this restriction can be bypassed using a specially crafted KERNEL_UID or KERNEL_GID value. This input validation vulnerability allows running Jupyter kernels as root, which can be dangerous as it allows more attack surface, and may lead to container escapes, compromising the worker node and all workloads running on it. Repeated exploitation can compromise all worker nodes, and thus the entire Kubernetes cluster. It is possible to specify volume mounts, so one vector for a container escape is to use a hostPath R/W volume mount, use this UID/GID bypass to run as root, and then gain code execution in the underlying worker node by creating a crontab entry in the mounted host file system. This issue has been fixed in version 3.0.0.
- Product
- enterprise_gateway
- What to do
- Apply the vendor’s update. The NVD record links to the advisory.
Jun 22, 2026Jupyter Server is the backend for Jupyter web applications.CVE-2026-44727 · Other software · jupyter-server · reported by GitHubCritical 9.3
Jupyter Server is the backend for Jupyter web applications. Prior to 2.20, the nbconvert HTTP handlers in jupyter_server render user-authored notebook HTML under the Jupyter origin without a sandbox directive in their Content-Security-Policy. Combined with nbconvert.HTMLExporter's default non-sanitizing behavior, a notebook carrying an HTML payload in a display_data output triggers stored XSS with cookie access, full /api/* authority, and kernel RCE. This vulnerability is fixed in 2.20.
- Product
- jupyter_server
- What to do
- Apply the vendor’s update. The NVD record links to the advisory.
Jun 3, 2026A vulnerability in jupyter-server versions 1.12.0 through 2.17.0 allows an attacker to bypass CORS origin validation when the `allow_origin_pat` configuration iCVE-2026-6657 · Other software · jupyter · reported by security@huntr.devHigh 8.8
A vulnerability in jupyter-server versions 1.12.0 through 2.17.0 allows an attacker to bypass CORS origin validation when the `allow_origin_pat` configuration is used. The issue arises from the use of `re.match()` for validating the `Origin` header, which only anchors at the start of the string. This allows attacker-controlled domains such as `trusted.example.com.evil.com` to pass validation against patterns intended to match `trusted.example.com`. The vulnerability affects multiple locations in the codebase, including CORS headers, WebSocket connections, referer validation, and login redirects, potentially enabling phishing attacks, arbitrary code execution, and unauthorized access to sensitive API responses.
- Product
- jupyter/jupyter
- What to do
- Apply the vendor’s update. The NVD record links to the advisory.
Jun 2, 2026A path traversal vulnerability exists in jupyter-server version 2.17.0 due to an incorrect root directory boundary check in the _get_os_path() function within jCVE-2026-5422 · Other software · jupyter · reported by security@huntr.devHigh 8.1
A path traversal vulnerability exists in jupyter-server version 2.17.0 due to an incorrect root directory boundary check in the _get_os_path() function within jupyter_server/services/contents/fileio.py. The check uses startswith(root) without appending a trailing path separator, allowing sibling directories with names starting with the same prefix as root_dir to bypass the check. Additionally, the to_os_path() function in utils.py does not strip ".." from path parts, enabling traversal sequences to bypass the vulnerable check. This vulnerability can lead to unauthorized read/write access to files in sibling directories, potentially exposing sensitive data in shared hosting environments.
- Product
- jupyter/jupyter
- What to do
- Apply the vendor’s update. The NVD record links to the advisory.
May 5, 2026Jupyter Server is the backend for Jupyter web applications.CVE-2026-40934 · Other software · jupyter-server · reported by GitHubHigh 7.6
Jupyter Server is the backend for Jupyter web applications. In versions 2.17.0 and earlier, the secret used to sign authentication cookies is persisted to a static file at ~/.local/share/jupyter/runtime/jupyter_cookie_secret and is never rotated when a user changes their password. After a password reset and server restart, any previously issued authentication cookie remains cryptographically valid because the signing key has not changed. An attacker who has captured a session cookie through any means retains full authenticated access to the server regardless of subsequent password changes. This affects deployments using password-based authentication, particularly shared or public-facing servers where credential rotation is expected to revoke existing sessions. This issue has been fixed in version 2.18.0.
- Product
- jupyter_server
- What to do
- Apply the vendor’s update. The NVD record links to the advisory.
May 5, 2026Jupyter Server is the backend for Jupyter web applications.CVE-2026-40110 · Other software · jupyter-server · reported by GitHubHigh 7.6
Jupyter Server is the backend for Jupyter web applications. In versions 2.17.0 and earlier, the Origin header validation uses Python's re.match() to check incoming origins against the allow_origin_pat configuration value. Because re.match() only anchors at the start of the string and does not require a full match, a pattern intended to match only a trusted domain (e.g., trusted.example.com) will also match any origin that begins with that domain followed by additional characters (e.g., trusted.example.com.evil.com). An attacker who controls such a domain can bypass the CORS origin restriction and make cross-origin requests to the Jupyter Server API from an untrusted site. This issue has been fixed in version 2.18.0.
- Product
- jupyter_server
- What to do
- Apply the vendor’s update. The NVD record links to the advisory.
May 5, 2026Jupyter Server is the backend for Jupyter web applications.CVE-2026-35397 · Other software · jupyter-server · reported by GitHubHigh 7.6
Jupyter Server is the backend for Jupyter web applications. In versions 2.17.0 and earlier, a path traversal vulnerability in the REST API allows an authenticated user to escape the configured root_dir and access sibling directories whose names begin with the same prefix as the root_dir. For example, with a root_dir named "test", the API permits access to a sibling directory named "testtest" through a crafted request to the /api/contents endpoint using encoded path components. An attacker can read, write, and delete files in affected sibling directories. Multi-tenant deployments using predictable naming schemes are particularly at risk, as a user with a directory named "user1" could access directories for user10 through user19 and beyond. A user who can choose a single-character folder name could gain access to a significant number of sibling directories. Version 2.18.0 contains a fix. As a workaround, ensure folder names do not share a common prefix with any sibling directory.
- Product
- jupyter_server
- What to do
- Apply the vendor’s update. The NVD record links to the advisory.
Full record and what to do →NVD recordgithub.comaccess.redhat.com
May 5, 2026Jupyter Server is the backend for Jupyter web applications.CVE-2025-61669 · Other software · jupyter-server · reported by GitHubMedium 6.3
Jupyter Server is the backend for Jupyter web applications. In jupyter_server versions through 2.17.0, the next query parameter in the login flow is insufficiently validated in `LoginFormHandler._redirect_safe()`, which allows redirects to arbitrary external domains via values such as `///example.com`. An attacker can use a crafted login URL to redirect users to a malicious site and facilitate phishing attacks. This issue is fixed in version 2.18.0.
- Product
- jupyter_server
- What to do
- Apply the vendor’s update. The NVD record links to the advisory.
Jun 11, 2024Jupyter Server Proxy allows users to run arbitrary external processes alongside their notebook server and provide authenticated web access to them.CVE-2024-35225 · Other software · jupyterhub · reported by GitHubCritical 9.6
Jupyter Server Proxy allows users to run arbitrary external processes alongside their notebook server and provide authenticated web access to them. Versions of 3.x prior to 3.2.4 and 4.x prior to 4.2.0 have a reflected cross-site scripting (XSS) issue. The `/proxy` endpoint accepts a `host` path segment in the format `/proxy/<host>`. When this endpoint is called with an invalid `host` value, `jupyter-server-proxy` replies with a response that includes the value of `host`, without sanitization [2]. A third-party actor can leverage this by sending a phishing link with an invalid `host` value containing custom JavaScript to a user. When the user clicks this phishing link, the browser renders the response of `GET /proxy/<host>`, which runs the custom JavaScript contained in `host` set by the actor. As any arbitrary JavaScript can be run after the user clicks on a phishing link, this issue permits extensive access to the user's JupyterLab instance for an actor. Patches are included in versions 4.2.0 and 3.2.4. As a workaround, server operators who are unable to upgrade can disable the `jupyter-server-proxy` extension.
- Product
- jupyter-server-proxy
- What to do
- Apply the vendor’s update. The NVD record links to the advisory.
Jun 6, 2024The Jupyter Server provides the backend for Jupyter web applications.CVE-2024-35178 · Other software · jupyter-server · reported by GitHubHigh 7.5
The Jupyter Server provides the backend for Jupyter web applications. Jupyter Server on Windows has a vulnerability that lets unauthenticated attackers leak the NTLMv2 password hash of the Windows user running the Jupyter server. An attacker can crack this password to gain access to the Windows machine hosting the Jupyter server, or access other network-accessible machines or 3rd party services using that credential. Or an attacker perform an NTLM relay attack without cracking the credential to gain access to other network-accessible machines. This vulnerability is fixed in 2.14.1.
- Product
- jupyter_server
- What to do
- Apply the vendor’s update. The NVD record links to the advisory.
May 23, 2024Jupyter Scheduler is collection of extensions for programming jobs to run now or run on a schedule.CVE-2024-28188 · Other software · jupyter-server · reported by GitHubMedium 5.3
Jupyter Scheduler is collection of extensions for programming jobs to run now or run on a schedule. The list of conda environments of `jupyter-scheduler` users maybe be exposed, potentially revealing information about projects that a specific user may be working on. This vulnerability has been patched in version(s) 1.1.6, 1.2.1, 1.8.2 and 2.5.2.
- Product
- jupyter-scheduler
- What to do
- Apply the vendor’s update. The NVD record links to the advisory.
Mar 20, 2024Jupyter Server Proxy allows users to run arbitrary external processes alongside their Jupyter notebook servers and provides authenticated web access.CVE-2024-28179 · Other software · jupyterhub · reported by GitHubCritical 9
Jupyter Server Proxy allows users to run arbitrary external processes alongside their Jupyter notebook servers and provides authenticated web access. Prior to versions 3.2.3 and 4.1.1, Jupyter Server Proxy did not check user authentication appropriately when proxying websockets, allowing unauthenticated access to anyone who had network access to the Jupyter server endpoint. This vulnerability can allow unauthenticated remote access to any websocket endpoint set up to be accessible via Jupyter Server Proxy. In many cases, this leads to remote unauthenticated arbitrary code execution, due to how affected instances use websockets. The websocket endpoints exposed by `jupyter_server` itself is not affected. Projects that do not rely on websockets are also not affected. Versions 3.2.3 and 4.1.1 contain a fix for this issue.
- Product
- jupyter-server-proxy
- What to do
- Apply the vendor’s update. The NVD record links to the advisory.
Dec 4, 2023The Jupyter Server provides the backend (i.e.CVE-2023-49080 · Other software · jupyter-server · reported by GitHubLow 3.5
The Jupyter Server provides the backend (i.e. the core services, APIs, and REST endpoints) for Jupyter web applications like Jupyter notebook, JupyterLab, and Voila. Unhandled errors in API requests coming from an authenticated user include traceback information, which can include path information. There is no known mechanism by which to trigger these errors without authentication, so the paths revealed are not considered particularly sensitive, given that the requesting user has arbitrary execution permissions already in the same environment. A fix has been introduced in commit `0056c3aa52` which no longer includes traceback information in JSON error responses. For compatibility, the traceback field is present, but always empty. This commit has been included in version 2.11.2. Users are advised to upgrade. There are no known workarounds for this vulnerability.
- Product
- jupyter_server
- What to do
- Apply the vendor’s update. The NVD record links to the advisory.
Aug 28, 2023jupyter-server is the backend for Jupyter web applications.CVE-2023-40170 · Other software · jupyter-server · reported by GitHubMedium 4.6
jupyter-server is the backend for Jupyter web applications. Improper cross-site credential checks on `/files/` URLs could allow exposure of certain file contents, or accessing files when opening untrusted files via "Open image in new tab". This issue has been addressed in commit `87a49272728` which has been included in release `2.7.2`. Users are advised to upgrade. Users unable to upgrade may use the lower performance `--ContentsManager.files_handler_class=jupyter_server.files.handlers.FilesHandler`, which implements the correct checks.
- Product
- jupyter_server
- What to do
- Apply the vendor’s update. The NVD record links to the advisory.
Aug 28, 2023jupyter-server is the backend for Jupyter web applications.CVE-2023-39968 · Other software · jupyter-server · reported by GitHubMedium 4.3
jupyter-server is the backend for Jupyter web applications. Open Redirect Vulnerability. Maliciously crafted login links to known Jupyter Servers can cause successful login or an already logged-in session to be redirected to arbitrary sites, which should be restricted to Jupyter Server-served URLs. This issue has been addressed in commit `29036259` which is included in release 2.7.2. Users are advised to upgrade. There are no known workarounds for this vulnerability.
- Product
- jupyter_server
- What to do
- Apply the vendor’s update. The NVD record links to the advisory.
Jun 14, 2022Jupyter Server provides the backend (i.e.CVE-2022-29241 · Other software · jupyter-server · reported by GitHubHigh 7.1
Jupyter Server provides the backend (i.e. the core services, APIs, and REST endpoints) for Jupyter web applications like Jupyter Notebook. Prior to version 1.17.1, if notebook server is started with a value of `root_dir` that contains the starting user's home directory, then the underlying REST API can be used to leak the access token assigned at start time by guessing/brute forcing the PID of the jupyter server. While this requires an authenticated user session, this URL can be used from a cross-site scripting payload or from a hooked or otherwise compromised browser to leak this access token to a malicious third party. This token can be used along with the REST API to interact with Jupyter services/notebooks such as modifying or overwriting critical files, such as .bashrc or .ssh/authorized_keys, allowing a malicious user to read potentially sensitive data and possibly gain control of the impacted system. This issue is patched in version 1.17.1.
- Product
- jupyter_server
- What to do
- Apply the vendor’s update. The NVD record links to the advisory.
Mar 23, 2022The Jupyter Server provides the backend (i.e.CVE-2022-24757 · Other software · jupyter-server · reported by GitHubHigh 7.5
The Jupyter Server provides the backend (i.e. the core services, APIs, and REST endpoints) for Jupyter web applications. Prior to version 1.15.4, unauthorized actors can access sensitive information from server logs. Anytime a 5xx error is triggered, the auth cookie and other header values are recorded in Jupyter Server logs by default. Considering these logs do not require root access, an attacker can monitor these logs, steal sensitive auth/cookie information, and gain access to the Jupyter server. Jupyter Server version 1.15.4 contains a patch for this issue. There are currently no known workarounds.
- Product
- jupyter_server
- What to do
- Apply the vendor’s update. The NVD record links to the advisory.
Jan 25, 2022Jupyter Server Proxy is a Jupyter notebook server extension to proxy web services.CVE-2022-21697 · Other software · jupyterhub · reported by GitHubMedium 6.3
Jupyter Server Proxy is a Jupyter notebook server extension to proxy web services. Versions of Jupyter Server Proxy prior to 3.2.1 are vulnerable to Server-Side Request Forgery (SSRF). Any user deploying Jupyter Server or Notebook with jupyter-proxy-server extension enabled is affected. A lack of input validation allows authenticated clients to proxy requests to other hosts, bypassing the `allowed_hosts` check. Because authentication is required, which already grants permissions to make the same requests via kernel or terminal execution, this is considered low to moderate severity. Users may upgrade to version 3.2.1 to receive a patch or, as a workaround, install the patch manually.
- Product
- jupyter-server-proxy
- What to do
- Apply the vendor’s update. The NVD record links to the advisory.
Aug 25, 2021nbgitpuller is a Jupyter server extension to sync a git repository one-way to a local path.CVE-2021-39160 · Other software · jupyterhub · reported by GitHubCritical 9.6
nbgitpuller is a Jupyter server extension to sync a git repository one-way to a local path. Due to unsanitized input, visiting maliciously crafted links could result in arbitrary code execution in the user environment. This has been resolved in version 0.10.2 and all users are advised to upgrade. No work around exist for users who can not upgrade.
- Product
- nbgitpuller
- What to do
- Apply the vendor’s update. The NVD record links to the advisory.
Dec 21, 2020The Jupyter Server provides the backend (i.e.CVE-2020-26275 · Other software · jupyter-server · reported by GitHubMedium 6.1
The Jupyter Server provides the backend (i.e. the core services, APIs, and REST endpoints) for Jupyter web applications like Jupyter notebook, JupyterLab, and Voila. In Jupyter Server before version 1.1.1, an open redirect vulnerability could cause the jupyter server to redirect the browser to a different malicious website. All jupyter servers running without a base_url prefix are technically affected, however, these maliciously crafted links can only be reasonably made for known jupyter server hosts. A link to your jupyter server may *appear* safe, but ultimately redirect to a spoofed server on the public internet. This same vulnerability was patched in upstream notebook v5.7.8. This is fixed in jupyter_server 1.1.1. If upgrade is not available, a workaround can be to run your server on a url prefix: "jupyter server --ServerApp.base_url=/jupyter/".
- Product
- jupyter_server
- What to do
- Apply the vendor’s update. The NVD record links to the advisory.
Full record and what to do →NVD recordadvisory.checkmarx.netgithub.com
Nov 24, 2020Jupyter Server before version 1.0.6 has an Open redirect vulnerability.CVE-2020-26232 · Other software · jupyter · reported by GitHubMedium 4.1
Jupyter Server before version 1.0.6 has an Open redirect vulnerability. A maliciously crafted link to a jupyter server could redirect the browser to a different website. All jupyter servers are technically affected, however, these maliciously crafted links can only be reasonably made for known jupyter server hosts. A link to your jupyter server may appear safe, but ultimately redirect to a spoofed server on the public internet.
- Product
- jupyter_server
- What to do
- Apply the vendor’s update. The NVD record links to the advisory.
Where this comes from: the exploited list is CISA’s Known Exploited Vulnerabilities catalog. Everything else is the whole National Vulnerability Database, where each record is published by the team that found the bug (Wordfence, Patchstack, WPScan, the vendors themselves and others); we show who. Exploit odds are FIRST’s EPSS, updated daily. Titles and categories are ours, so check the linked record before acting on a detail. For a write-up of the big ones, see our advisories. Every vendor, and every WordPress plugin and theme with a recorded flaw, also has its own page. All of it is free to reuse as JSON, CSV or RSS.
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