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HuttenlocherTechnologies
Updated 2 h ago

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.

1,762exploited flaws on CISA’s list
34added in the last 30 days
344new WordPress flaws this week
390,080entries in the database

36 results

  • May 25, 2026PuTTY 0.71 before 0.84 has an assertion failure in ECDSA signature verification.CVE-2026-48852 · Other software · PuTTY · reported by MITRELow 3.7

    PuTTY 0.71 before 0.84 has an assertion failure in ECDSA signature verification.

    Product
    PuTTY
    What to do
    Apply the vendor’s update. The NVD record links to the advisory.
  • May 25, 2026PuTTY 0.77 before 0.84 uses a copy of the PuTTY icon as a trust indication for TELNET data but the trust status is not cleared between proxy authentication and CVE-2026-48851 · Other software · PuTTY · reported by MITRELow 3.1

    PuTTY 0.77 before 0.84 uses a copy of the PuTTY icon as a trust indication for TELNET data but the trust status is not cleared between proxy authentication and the main session.

    Product
    PuTTY
    What to do
    Apply the vendor’s update. The NVD record links to the advisory.
  • May 25, 2026PuTTY 0.72 before 0.84 has a double free in RSA KEX.CVE-2026-48850 · Other software · PuTTY · reported by MITRELow 3.7

    PuTTY 0.72 before 0.84 has a double free in RSA KEX.

    Product
    PuTTY
    What to do
    Apply the vendor’s update. The NVD record links to the advisory.
  • Mar 22, 2026A vulnerability was detected in PuTTY 0.83.CVE-2026-4115 · Other software · Putty · reported by VulDBLow 2.9

    A vulnerability was detected in PuTTY 0.83. Affected is the function eddsa_verify of the file crypto/ecc-ssh.c of the component Ed25519 Signature Handler. The manipulation results in improper verification of cryptographic signature. The attack may be performed from remote. The attack requires a high level of complexity. The exploitability is told to be difficult. The exploit is now public and may be used. The real existence of this vulnerability is still doubted at the moment. The patch is identified as af996b5ec27ab79bae3882071b9d6acf16044549. It is advisable to implement a patch to correct this issue. The vendor was contacted early, responded in a very professional manner and quickly released a patch for the affected product. However, at the moment there is no proof that this flaw might have any real-world impact.

    Product
    Putty
    What to do
    Apply the vendor’s update. The NVD record links to the advisory.
  • Jan 15, 2026MTPutty 1.0.1.21 contains a sensitive information disclosure vulnerability that allows local attackers to view SSH connection passwords through Windows PowerSheCVE-2021-47759 · Other software · Ttyplus · reported by VulnCheckMedium 6.8

    MTPutty 1.0.1.21 contains a sensitive information disclosure vulnerability that allows local attackers to view SSH connection passwords through Windows PowerShell process listing. Attackers can run a PowerShell command to retrieve the full command line of MTPutty processes, exposing plaintext SSH credentials.

    Product
    MTPutty
    What to do
    Apply the vendor’s update. The NVD record links to the advisory.
  • Apr 15, 2024In PuTTY 0.68 through 0.80 before 0.81, biased ECDSA nonce generation allows an attacker to recover a user's NIST P-521 secret key via a quick attack in approxiCVE-2024-31497 · Other software · putty · reported by MITREMedium 5.9

    In PuTTY 0.68 through 0.80 before 0.81, biased ECDSA nonce generation allows an attacker to recover a user's NIST P-521 secret key via a quick attack in approximately 60 signatures. This is especially important in a scenario where an adversary is able to read messages signed by PuTTY or Pageant. The required set of signed messages may be publicly readable because they are stored in a public Git service that supports use of SSH for commit signing, and the signatures were made by Pageant through an agent-forwarding mechanism. In other words, an adversary may already have enough signature information to compromise a victim's private key, even if there is no further use of vulnerable PuTTY versions. After a key compromise, an adversary may be able to conduct supply-chain attacks on software maintained in Git. A second, independent scenario is that the adversary is an operator of an SSH server to which the victim authenticates (for remote login or file copy), even though this server is not fully trusted by the victim, and the victim uses the same private key for SSH connections to other services operated by other entities. Here, the rogue server operator (who would otherwise have no way

    Product
    putty
    What to do
    Apply the vendor’s update. The NVD record links to the advisory.
  • Jul 9, 2021PuTTY through 0.75 proceeds with establishing an SSH session even if it has never sent a substantive authentication response.CVE-2021-36367 · Other software · putty · reported by MITREHigh 8.1

    PuTTY through 0.75 proceeds with establishing an SSH session even if it has never sent a substantive authentication response. This makes it easier for an attacker-controlled SSH server to present a later spoofed authentication prompt (that the attacker can use to capture credential data, and use that data for purposes that are undesired by the client user).

    Product
    putty
    What to do
    Apply the vendor’s update. The NVD record links to the advisory.
  • May 21, 2021PuTTY before 0.75 on Windows allows remote servers to cause a denial of service (Windows GUI hang) by telling the PuTTY window to change its title repeatedly atCVE-2021-33500 · Other software · Putty · reported by MITREHigh 7.5

    PuTTY before 0.75 on Windows allows remote servers to cause a denial of service (Windows GUI hang) by telling the PuTTY window to change its title repeatedly at high speed, which results in many SetWindowTextA or SetWindowTextW calls. NOTE: the same attack methodology may affect some OS-level GUIs on Linux or other platforms for similar reasons.

    Product
    Putty
    What to do
    Apply the vendor’s update. The NVD record links to the advisory.
  • Jan 28, 2021OnCommand Unified Manager Core Package versions prior to 5.2.5 may disclose sensitive account information to unauthorized users via the use of PuTTY Link (plinkCVE-2020-8585 · Other software · Netapp · reported by security-alert@netapp.comMedium 5.5

    OnCommand Unified Manager Core Package versions prior to 5.2.5 may disclose sensitive account information to unauthorized users via the use of PuTTY Link (plink).

    Product
    Oncommand Unified Manager
    What to do
    Apply the vendor’s update. The NVD record links to the advisory.
  • Jun 29, 2020PuTTY 0.68 through 0.73 has an Observable Discrepancy leading to an information leak in the algorithm negotiation.CVE-2020-14002 · Other software · Putty · reported by MITREMedium 5.9

    PuTTY 0.68 through 0.73 has an Observable Discrepancy leading to an information leak in the algorithm negotiation. This allows man-in-the-middle attackers to target initial connection attempts (where no host key for the server has been cached by the client).

    Product
    Putty
    What to do
    Apply the vendor’s update. The NVD record links to the advisory.
  • Oct 1, 2019PuTTY before 0.73 might allow remote SSH-1 servers to cause a denial of service by accessing freed memory locations via an SSH1_MSG_DISCONNECT message.CVE-2019-17069 · Other software · Putty · reported by MITREHigh 7.5

    PuTTY before 0.73 might allow remote SSH-1 servers to cause a denial of service by accessing freed memory locations via an SSH1_MSG_DISCONNECT message.

    Product
    Putty
    What to do
    Apply the vendor’s update. The NVD record links to the advisory.
  • Oct 1, 2019PuTTY before 0.73 mishandles the "bracketed paste mode" protection mechanism, which may allow a session to be affected by malicious clipboard content.CVE-2019-17068 · Other software · Putty · reported by MITREHigh 7.5

    PuTTY before 0.73 mishandles the "bracketed paste mode" protection mechanism, which may allow a session to be affected by malicious clipboard content.

    Product
    Putty
    What to do
    Apply the vendor’s update. The NVD record links to the advisory.
  • Oct 1, 2019PuTTY before 0.73 on Windows improperly opens port-forwarding listening sockets, which allows attackers to listen on the same port to steal an incoming connectiCVE-2019-17067 · Other software · Putty · reported by MITRECritical 9.8

    PuTTY before 0.73 on Windows improperly opens port-forwarding listening sockets, which allows attackers to listen on the same port to steal an incoming connection.

    Product
    Putty
    What to do
    Apply the vendor’s update. The NVD record links to the advisory.
  • Mar 21, 2019Potential recycling of random numbers used in cryptography exists within PuTTY before 0.71.CVE-2019-9898 · Other software · Putty · reported by MITRECritical 9.8

    Potential recycling of random numbers used in cryptography exists within PuTTY before 0.71.

    Product
    Putty
    What to do
    Apply the vendor’s update. The NVD record links to the advisory.
  • Mar 21, 2019Multiple denial-of-service attacks that can be triggered by writing to the terminal exist in PuTTY versions before 0.71.CVE-2019-9897 · Other software · Putty · reported by MITREHigh 7.5

    Multiple denial-of-service attacks that can be triggered by writing to the terminal exist in PuTTY versions before 0.71.

    Product
    Putty
    What to do
    Apply the vendor’s update. The NVD record links to the advisory.
  • Mar 21, 2019In PuTTY versions before 0.71 on Windows, local attackers could hijack the application by putting a malicious help file in the same directory as the executable.CVE-2019-9896 · Other software · Putty · reported by MITREHigh 7.8

    In PuTTY versions before 0.71 on Windows, local attackers could hijack the application by putting a malicious help file in the same directory as the executable.

    Product
    Putty
    What to do
    Apply the vendor’s update. The NVD record links to the advisory.
  • Mar 21, 2019In PuTTY versions before 0.71 on Unix, a remotely triggerable buffer overflow exists in any kind of server-to-client forwarding.CVE-2019-9895 · Other software · Putty · reported by MITRECritical 9.8

    In PuTTY versions before 0.71 on Unix, a remotely triggerable buffer overflow exists in any kind of server-to-client forwarding.

    Product
    Putty
    What to do
    Apply the vendor’s update. The NVD record links to the advisory.
  • Mar 21, 2019A remotely triggerable memory overwrite in RSA key exchange in PuTTY before 0.71 can occur before host key verification.CVE-2019-9894 · Other software · Putty · reported by MITREHigh 7.5

    A remotely triggerable memory overwrite in RSA key exchange in PuTTY before 0.71 can occur before host key verification.

    Product
    Putty
    What to do
    Apply the vendor’s update. The NVD record links to the advisory.
  • Mar 27, 2017The TFTP server in ExtraPuTTY 0.30 and earlier allows remote attackers to cause a denial of service (crash) via a large (1) read or (2) write TFTP protocol messCVE-2017-7183 · Other software · Extraputty · reported by MITREHigh 7.5

    The TFTP server in ExtraPuTTY 0.30 and earlier allows remote attackers to cause a denial of service (crash) via a large (1) read or (2) write TFTP protocol message.

    Product
    Extraputty
    What to do
    Apply the vendor’s update. The NVD record links to the advisory.
  • Mar 27, 2017The ssh_agent_channel_data function in PuTTY before 0.68 allows remote attackers to have unspecified impact via a large length value in an agent protocol messagCVE-2017-6542 · Other software · Putty · reported by MITRECritical 9.8

    The ssh_agent_channel_data function in PuTTY before 0.68 allows remote attackers to have unspecified impact via a large length value in an agent protocol message and leveraging the ability to connect to the Unix-domain socket representing the forwarded agent connection, which trigger a buffer overflow.

    Product
    Putty
    What to do
    Apply the vendor’s update. The NVD record links to the advisory.
  • Jan 30, 2017Multiple untrusted search path vulnerabilities in Putty beta 0.67 allow local users to execute arbitrary code and conduct DLL hijacking attacks via a Trojan horCVE-2016-6167 · Other software · Putty · reported by MITREHigh 7.8

    Multiple untrusted search path vulnerabilities in Putty beta 0.67 allow local users to execute arbitrary code and conduct DLL hijacking attacks via a Trojan horse (1) UxTheme.dll or (2) ntmarta.dll file in the current working directory.

    Product
    Putty
    What to do
    Apply the vendor’s update. The NVD record links to the advisory.
  • Apr 7, 2016Stack-based buffer overflow in the SCP command-line utility in PuTTY before 0.67 and KiTTY 0.66.6.3 and earlier allows remote servers to cause a denial of serviCVE-2016-2563 · Other software · 9bis · reported by MITRECritical 9.8

    Stack-based buffer overflow in the SCP command-line utility in PuTTY before 0.67 and KiTTY 0.66.6.3 and earlier allows remote servers to cause a denial of service (stack memory corruption) or execute arbitrary code via a crafted SCP-SINK file-size response to an SCP download request.

    Product
    Kitty
    What to do
    Apply the vendor’s update. The NVD record links to the advisory.
  • Mar 13, 2016The ImageInputType::ensurePrimaryContent function in WebKit/Source/core/html/forms/ImageInputType.cpp in Blink, as used in Google Chrome before 49.0.2623.87, doCVE-2016-1643 · Computers, phones & browsers · Google · reported by chrome-cve-admin@google.comHigh 8.8

    The ImageInputType::ensurePrimaryContent function in WebKit/Source/core/html/forms/ImageInputType.cpp in Blink, as used in Google Chrome before 49.0.2623.87, does not properly maintain the user agent shadow DOM, which allows remote attackers to cause a denial of service or possibly have unspecified other impact via vectors that leverage "type confusion."

    Product
    Chrome
    What to do
    Apply the vendor’s update. The NVD record links to the advisory.
  • Dec 7, 2015Integer overflow in the terminal emulator in PuTTY before 0.66 allows remote attackers to cause a denial of service (memory corruption) or possibly execute arbiCVE-2015-5309 · Other software · Opensuse · reported by Red HatMedium 4.3

    Integer overflow in the terminal emulator in PuTTY before 0.66 allows remote attackers to cause a denial of service (memory corruption) or possibly execute arbitrary code via an ECH (erase characters) escape sequence with a large parameter value, which triggers a buffer underflow.

    Product
    Leap
    What to do
    Apply the vendor’s update. The NVD record links to the advisory.
  • Mar 27, 2015The (1) ssh2_load_userkey and (2) ssh2_save_userkey functions in PuTTY 0.51 through 0.63 do not properly wipe SSH-2 private keys from memory, which allows localCVE-2015-2157 · Other software · Debian · reported by MITRELow 2.1

    The (1) ssh2_load_userkey and (2) ssh2_save_userkey functions in PuTTY 0.51 through 0.63 do not properly wipe SSH-2 private keys from memory, which allows local users to obtain sensitive information by reading the memory.

    Product
    Debian Linux
    What to do
    Apply the vendor’s update. The NVD record links to the advisory.
  • Aug 23, 2013PuTTY 0.59 through 0.61 does not clear sensitive process memory when managing user replies that occur during keyboard-interactive authentication, which might alCVE-2011-4607 · Other software · Putty · reported by Red HatLow 2.1

    PuTTY 0.59 through 0.61 does not clear sensitive process memory when managing user replies that occur during keyboard-interactive authentication, which might allow local users to read login passwords by obtaining access to the process' memory.

    Product
    Putty
    What to do
    Apply the vendor’s update. The NVD record links to the advisory.
  • Aug 19, 2013Integer overflow in PuTTY 0.62 and earlier, WinSCP before 5.1.6, and other products that use PuTTY allows remote SSH servers to cause a denial of service (crashCVE-2013-4852 · Other software · Winscp · reported by MITREMedium 6.8

    Integer overflow in PuTTY 0.62 and earlier, WinSCP before 5.1.6, and other products that use PuTTY allows remote SSH servers to cause a denial of service (crash) and possibly execute arbitrary code in certain applications that use PuTTY via a negative size value in an RSA key signature during the SSH handshake, which triggers a heap-based buffer overflow.

    Product
    Winscp
    What to do
    Apply the vendor’s update. The NVD record links to the advisory.
  • Aug 19, 2013The rsa_verify function in PuTTY before 0.63 (1) does not clear sensitive process memory after use and (2) does not free certain structures containing sensitiveCVE-2013-4208 · Other software · Putty · reported by Red HatLow 2.1

    The rsa_verify function in PuTTY before 0.63 (1) does not clear sensitive process memory after use and (2) does not free certain structures containing sensitive process memory, which might allow local users to discover private RSA and DSA keys.

    Product
    Putty
    What to do
    Apply the vendor’s update. The NVD record links to the advisory.
  • Aug 19, 2013Buffer overflow in sshbn.c in PuTTY before 0.63 allows remote SSH servers to cause a denial of service (crash) via an invalid DSA signature that is not properlyCVE-2013-4207 · Other software · Putty · reported by Red HatMedium 4.3

    Buffer overflow in sshbn.c in PuTTY before 0.63 allows remote SSH servers to cause a denial of service (crash) via an invalid DSA signature that is not properly handled during computation of a modular inverse and triggers the overflow during a division by zero by the bignum functionality, a different vulnerability than CVE-2013-4206.

    Product
    Putty
    What to do
    Apply the vendor’s update. The NVD record links to the advisory.
  • Aug 19, 2013Heap-based buffer underflow in the modmul function in sshbn.c in PuTTY before 0.63 allows remote SSH servers to cause a denial of service (crash) and possibly tCVE-2013-4206 · Other software · Putty · reported by Red HatMedium 6.8

    Heap-based buffer underflow in the modmul function in sshbn.c in PuTTY before 0.63 allows remote SSH servers to cause a denial of service (crash) and possibly trigger memory corruption or code execution via a crafted DSA signature, which is not properly handled when performing certain bit-shifting operations during modular multiplication.

    Product
    Putty
    What to do
    Apply the vendor’s update. The NVD record links to the advisory.
  • Mar 7, 2007PuTTY 0.59 and earlier uses weak file permissions for (1) ppk files containing private keys generated by puttygen and (2) session logs created by putty, which aCVE-2006-7162 · Other software · Putty · reported by MITRELow 1.9

    PuTTY 0.59 and earlier uses weak file permissions for (1) ppk files containing private keys generated by puttygen and (2) session logs created by putty, which allows local users to gain sensitive information by reading these files.

    Product
    Putty
    What to do
    Apply the vendor’s update. The NVD record links to the advisory.
  • Feb 21, 2005Multiple integer overflows in the (1) sftp_pkt_getstring and (2) fxp_readdir_recv functions in the PSFTP and PSCP clients for PuTTY 0.56, and possibly earlier vCVE-2005-0467 · Other software · Putty · reported by MITREHigh 7.5

    Multiple integer overflows in the (1) sftp_pkt_getstring and (2) fxp_readdir_recv functions in the PSFTP and PSCP clients for PuTTY 0.56, and possibly earlier versions, allow remote malicious web sites to execute arbitrary code via SFTP responses that corrupt the heap after insufficient memory has been allocated.

    Product
    Putty
    What to do
    Apply the vendor’s update. The NVD record links to the advisory.
  • Jan 10, 2005Integer signedness error in the ssh2_rdpkt function in PuTTY before 0.56 allows remote attackers to execute arbitrary code via a SSH2_MSG_DEBUG packet with a moCVE-2004-1008 · Other software · Putty · reported by MITREHigh 10

    Integer signedness error in the ssh2_rdpkt function in PuTTY before 0.56 allows remote attackers to execute arbitrary code via a SSH2_MSG_DEBUG packet with a modified stringlen parameter, which leads to a buffer overflow.

    Product
    Putty
    What to do
    Apply the vendor’s update. The NVD record links to the advisory.
  • Dec 31, 2004Multiple heap-based buffer overflows in the modpow function in PuTTY before 0.55 allow (1) remote attackers to execute arbitrary code via an SSH2 packet with a CVE-2004-1440 · Other software · Putty · reported by MITREHigh 7.5

    Multiple heap-based buffer overflows in the modpow function in PuTTY before 0.55 allow (1) remote attackers to execute arbitrary code via an SSH2 packet with a base argument that is larger than the mod argument, which causes the modpow function to write memory before the beginning of its buffer, and (2) remote malicious servers to cause a denial of service (client crash) and possibly execute arbitrary code via a large bignum during authentication.

    Product
    Putty
    What to do
    Apply the vendor’s update. The NVD record links to the advisory.
  • Mar 18, 2003The PuTTY terminal emulator 0.53 allows attackers to modify the window title via a certain character escape sequence and then insert it back to the command lineCVE-2003-0069 · Other software · Putty · reported by MITREHigh 7.5

    The PuTTY terminal emulator 0.53 allows attackers to modify the window title via a certain character escape sequence and then insert it back to the command line in the user's terminal, e.g. when the user views a file containing the malicious sequence, which could allow the attacker to execute arbitrary commands.

    Product
    Putty
    What to do
    Apply the vendor’s update. The NVD record links to the advisory.
  • Feb 19, 2003PuTTY 0.53b and earlier does not clear logon credentials from memory, including plaintext passwords, which could allow attackers with access to memory to steal CVE-2003-0048 · Other software · Putty · reported by MITREMedium 4.6

    PuTTY 0.53b and earlier does not clear logon credentials from memory, including plaintext passwords, which could allow attackers with access to memory to steal the SSH credentials.

    Product
    Putty
    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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