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.
17 results
Oct 22, 2026multer is a middleware for Node.js that handles multipart/form-data file uploads.CVE-2026-113872 · Other software · multer · reported by ce714d77-add3-4f53-aff5-83d477b104bbHigh 7.5
multer is a middleware for Node.js that handles multipart/form-data file uploads. In versions from 2.0.0 before 2.5.0, when multer is configured with an asynchronous fileFilter, a single request can crash the Node.js process. If the request is aborted while one file's asynchronous fileFilter is still pending, the pending callback later resumes a parsing stream that multer has already torn down, and the underlying parser emits an error on a stream that no longer has an error listener, which Node raises as an unhandled error event so the process exits. Any application using multer with an asynchronous fileFilter is affected regardless of storage engine, while uploads using a synchronous fileFilter are not affected. The issue is fixed in multer 2.5.0, and users should upgrade to 2.5.0 or later. As a workaround, use a synchronous fileFilter.
- Product
- multer
- What to do
- Apply the vendor’s update. The NVD record links to the advisory.
Full record and what to do →NVD recordcna.openjsf.orggithub.com
Sep 14, 2026multer is a Node.js middleware for handling multipart/form-data uploads.CVE-2026-88932 · Other software · multer · reported by ce714d77-add3-4f53-aff5-83d477b104bbMedium 5.3
multer is a Node.js middleware for handling multipart/form-data uploads. In versions 2.2.0 through 2.3.0, when a request using disk storage is aborted mid-upload, file writes that complete after multer has already run its abort cleanup are not removed, so each aborted upload can leave an orphaned file on disk. A remote unauthenticated attacker can repeatedly start and abort uploads to accumulate orphaned files and exhaust disk space, causing a denial of service. The issue is fixed in multer 2.4.0, and users should upgrade to 2.4.0 or later.
- Product
- multer
- What to do
- Apply the vendor’s update. The NVD record links to the advisory.
Full record and what to do →NVD recordcna.openjsf.orggithub.com
Aug 28, 2026multer is a middleware for handling multipart/form-data in Node.js.CVE-2026-82333 · Other software · multer · reported by ce714d77-add3-4f53-aff5-83d477b104bbHigh 7.5
multer is a middleware for handling multipart/form-data in Node.js. A small multipart request with two specially crafted text field names can make multer's field parser synchronously iterate a maximum-length sparse array, blocking the event loop so the process cannot handle other requests. A large numeric array index in the first field allocates a maximum-length sparse array, and a second field with a non-numeric key then triggers a full-length iteration inside the append-field dependency. All versions before 2.3.0 are affected, and this is a remotely triggerable denial of service. multer 2.3.0 adds an opt-in fieldArrayIndexLimit option that rejects oversized array indexes. Upgrade to multer 2.3.0 and set limits.fieldArrayIndexLimit to the largest array index your application needs to remediate.
- Product
- multer
- What to do
- Apply the vendor’s update. The NVD record links to the advisory.
Full record and what to do →NVD recordcna.openjsf.orggithub.com
Aug 28, 2026multer is a middleware for handling multipart/form-data in Node.js.CVE-2026-77078 · Other software · multer · reported by ce714d77-add3-4f53-aff5-83d477b104bbHigh 7.5
multer is a middleware for handling multipart/form-data in Node.js. A small multipart request containing two specially crafted text field names can cause an uncaught RangeError (Invalid array length) that terminates the Node.js process. The first field uses a very large numeric array index to allocate a maximum-length sparse array, and a second field then pushes past that length, which throws inside the append-field dependency and is not caught by multer. All versions before 2.3.0 are affected, and the issue is a remotely triggerable denial of service. The issue is fixed in multer 2.3.0. Upgrade to multer 2.3.0 to remediate.
- Product
- multer
- What to do
- Apply the vendor’s update. The NVD record links to the advisory.
Full record and what to do →NVD recordcna.openjsf.orggithub.com
Aug 28, 2026multer is a middleware for handling multipart/form-data in Node.js.CVE-2026-77063 · Other software · multer · reported by ce714d77-add3-4f53-aff5-83d477b104bbLow 3.7
multer is a middleware for handling multipart/form-data in Node.js. When an application uses an asynchronous fileFilter together with the fileSize limit, a race condition in multer's file stream handling can allow a file that exceeds the configured size limit to bypass the size-limit rejection. All versions before 2.3.0 are affected. The impact is limited because the underlying multipart parser still truncates the stream at the size limit, so this is a bypass of the limit rejection rather than uncontrolled resource consumption. The issue is fixed in multer 2.3.0. Upgrade to multer 2.3.0 to remediate.
- Product
- multer
- What to do
- Apply the vendor’s update. The NVD record links to the advisory.
Full record and what to do →NVD recordcna.openjsf.orggithub.com
Aug 28, 2026multer is a middleware for handling multipart/form-data in Node.js.CVE-2026-77037 · Other software · multer · reported by ce714d77-add3-4f53-aff5-83d477b104bbHigh 7.5
multer is a middleware for handling multipart/form-data in Node.js. In version 2.2.0, when a disk-backed upload is aborted or truncated before the write stream finishes, multer's disk storage engine removes the visible file but does not close the underlying write file descriptor, leaving a deleted but still open descriptor. A remote attacker able to reach an upload route using the built-in disk storage can send repeated aborted or malformed multipart uploads, each one leaking a file descriptor and retaining disk blocks until the process exits, which can exhaust resources and cause a denial of service. The issue is fixed in multer 2.3.0, which closes the destination write stream on abnormal source termination and defers cleanup until the stream has closed. Upgrade to multer 2.3.0 to remediate.
- Product
- multer
- What to do
- Apply the vendor’s update. The NVD record links to the advisory.
Full record and what to do →NVD recordcna.openjsf.orggithub.com
Jun 15, 2026Impact: multer versions 2.0.0-alpha.1 through 2.1.1 and 3.0.0-alpha.1 are vulnerable to a Denial of Service when using diskStorage.CVE-2026-5038 · Other software · multer · reported by ce714d77-add3-4f53-aff5-83d477b104bbMedium 5.3
Impact: multer versions 2.0.0-alpha.1 through 2.1.1 and 3.0.0-alpha.1 are vulnerable to a Denial of Service when using diskStorage. Aborted or malformed multipart uploads leave orphaned partial files on disk because the Readable.pipe() call does not propagate the stream destroy signal to the underlying fs.WriteStream. An attacker can exhaust disk space by triggering many aborted uploads, with no application bug required. Patches: Users should upgrade to multer 2.2.0 (2.x line) or 3.0.0-alpha.2 (3.x prerelease). Both versions track in-flight write streams and clean them up on the abort path. Workarounds: None.
- Product
- multer
- What to do
- Apply the vendor’s update. The NVD record links to the advisory.
Full record and what to do →NVD recordcna.openjsf.orggithub.com
Jun 15, 2026Impact: multer versions 1.0.0 through 2.1.1 and 3.0.0-alpha.1 are vulnerable to a Denial of Service via deeply nested field names in multipart form data.CVE-2026-5079 · Other software · multer · reported by ce714d77-add3-4f53-aff5-83d477b104bbHigh 7.5
Impact: multer versions 1.0.0 through 2.1.1 and 3.0.0-alpha.1 are vulnerable to a Denial of Service via deeply nested field names in multipart form data. The append-field dependency parses bracket notation in field names with no limit on nesting depth, allowing an attacker to force allocation of deeply nested object structures that consume CPU and memory. A single HTTP request with a crafted multipart body is sufficient to exploit this. Patches: Users should upgrade to multer 2.2.0 (2.x line) or 3.0.0-alpha.2 (3.x prerelease) and configure the new limits.fieldNestingDepth option to the minimum depth their application requires. Workarounds: Set limits.fields to a reasonable value to reduce the number of fields an attacker can send per request. This does not fully mitigate the issue but limits the impact.
- Product
- multer
- What to do
- Apply the vendor’s update. The NVD record links to the advisory.
Full record and what to do →NVD recordcna.openjsf.orggithub.com
Mar 4, 2026Multer is a node.js middleware for handling `multipart/form-data`.CVE-2026-3520 · Other software · expressjs · reported by ce714d77-add3-4f53-aff5-83d477b104bbHigh 8.7
Multer is a node.js middleware for handling `multipart/form-data`. A vulnerability in Multer prior to version 2.1.1 allows an attacker to trigger a Denial of Service (DoS) by sending malformed requests, potentially causing stack overflow. Users should upgrade to version 2.1.1 to receive a patch. No known workarounds are available.
- Product
- multer
- What to do
- Apply the vendor’s update. The NVD record links to the advisory.
Full record and what to do →NVD recordcna.openjsf.orggithub.com
Feb 27, 2026Multer is a node.js middleware for handling `multipart/form-data`.CVE-2026-3304 · Other software · expressjs · reported by ce714d77-add3-4f53-aff5-83d477b104bbHigh 8.7
Multer is a node.js middleware for handling `multipart/form-data`. A vulnerability in Multer prior to version 2.1.0 allows an attacker to trigger a Denial of Service (DoS) by sending malformed requests, potentially causing resource exhaustion. Users should upgrade to version 2.1.0 to receive a patch. No known workarounds are available.
- Product
- multer
- What to do
- Apply the vendor’s update. The NVD record links to the advisory.
Full record and what to do →NVD recordcna.openjsf.orggithub.com
Feb 27, 2026Multer is a node.js middleware for handling `multipart/form-data`.CVE-2026-2359 · Other software · expressjs · reported by ce714d77-add3-4f53-aff5-83d477b104bbHigh 8.7
Multer is a node.js middleware for handling `multipart/form-data`. A vulnerability in Multer prior to version 2.1.0 allows an attacker to trigger a Denial of Service (DoS) by dropping connection during file upload, potentially causing resource exhaustion. Users should upgrade to version 2.1.0 to receive a patch. No known workarounds are available.
- Product
- multer
- What to do
- Apply the vendor’s update. The NVD record links to the advisory.
Full record and what to do →NVD recordcna.openjsf.orggithub.com
Jul 17, 2025Multer is a node.js middleware for handling `multipart/form-data`.CVE-2025-7338 · Other software · expressjs · reported by ce714d77-add3-4f53-aff5-83d477b104bbHigh 7.5
Multer is a node.js middleware for handling `multipart/form-data`. A vulnerability that is present starting in version 1.4.4-lts.1 and prior to version 2.0.2 allows an attacker to trigger a Denial of Service (DoS) by sending a malformed multi-part upload request. This request causes an unhandled exception, leading to a crash of the process. Users should upgrade to version 2.0.2 to receive a patch. No known workarounds are available.
- Product
- multer
- What to do
- Apply the vendor’s update. The NVD record links to the advisory.
Full record and what to do →NVD recordcna.openjsf.orggithub.com
Jun 3, 2025Multer is a node.js middleware for handling `multipart/form-data`.CVE-2025-48997 · Other software · expressjs · reported by GitHubHigh 8.7
Multer is a node.js middleware for handling `multipart/form-data`. A vulnerability that is present starting in version 1.4.4-lts.1 and prior to version 2.0.1 allows an attacker to trigger a Denial of Service (DoS) by sending an upload file request with an empty string field name. This request causes an unhandled exception, leading to a crash of the process. Users should upgrade to `2.0.1` to receive a patch. No known workarounds are available.
- Product
- multer
- What to do
- Apply the vendor’s update. The NVD record links to the advisory.
May 19, 2025Multer is a node.js middleware for handling `multipart/form-data`.CVE-2025-47944 · Other software · expressjs · reported by GitHubHigh 7.5
Multer is a node.js middleware for handling `multipart/form-data`. A vulnerability that is present starting in version 1.4.4-lts.1 and prior to version 2.0.0 allows an attacker to trigger a Denial of Service (DoS) by sending a malformed multi-part upload request. This request causes an unhandled exception, leading to a crash of the process. Users should upgrade to version 2.0.0 to receive a patch. No known workarounds are available.
- Product
- multer
- What to do
- Apply the vendor’s update. The NVD record links to the advisory.
May 19, 2025Multer is a node.js middleware for handling `multipart/form-data`.CVE-2025-47935 · Other software · expressjs · reported by GitHubHigh 7.5
Multer is a node.js middleware for handling `multipart/form-data`. Versions prior to 2.0.0 are vulnerable to a resource exhaustion and memory leak issue due to improper stream handling. When the HTTP request stream emits an error, the internal `busboy` stream is not closed, violating Node.js stream safety guidance. This leads to unclosed streams accumulating over time, consuming memory and file descriptors. Under sustained or repeated failure conditions, this can result in denial of service, requiring manual server restarts to recover. All users of Multer handling file uploads are potentially impacted. Users should upgrade to 2.0.0 to receive a patch. No known workarounds are available.
- Product
- multer
- What to do
- Apply the vendor’s update. The NVD record links to the advisory.
Mar 20, 2025A vulnerability in danny-avila/librechat version git 81f2936 allows for path traversal due to improper sanitization of file paths by the multer middleware.CVE-2024-11170 · Other software · danny-avila · reported by security@huntr.devHigh 8.8
A vulnerability in danny-avila/librechat version git 81f2936 allows for path traversal due to improper sanitization of file paths by the multer middleware. This can lead to arbitrary file write and potentially remote code execution. The issue is fixed in version 0.7.6.
- Product
- danny-avila/librechat
- What to do
- Apply the vendor’s update. The NVD record links to the advisory.
Feb 10, 2025A vulnerability in mintplex-labs/anything-llm prior to version 1.3.1 allows for path traversal due to improper handling of non-ASCII filenames in the multer libCVE-2024-13059 · Other software · mintplex-labs · reported by security@huntr.devHigh 7.2
A vulnerability in mintplex-labs/anything-llm prior to version 1.3.1 allows for path traversal due to improper handling of non-ASCII filenames in the multer library. This vulnerability can lead to arbitrary file write, which can subsequently result in remote code execution. The issue arises when the filename transformation introduces '../' sequences, which are not sanitized by multer, allowing attackers with manager or admin roles to write files to arbitrary locations on the server.
- Product
- mintplex-labs/anything-llm
- 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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