Aggregates CVE and security vulnerability intelligence across all putty-related products, including CVSS, EPSS, publication dates, and vulnerability intelligence data.
Disclosed issues often relate to vendor risk input validation, vendor risk path handling, and vendor risk memory corruption; exposure may include vendor impact memory corruption in vendor surface production workloads contexts.
| CVE | Summary | Source | Max CVSS | EPSS % | Published | Updated |
|---|---|---|---|---|---|---|
| CVE-2026-48852 | PuTTY 0.71 before 0.84 has an assertion failure in ECDSA signature verification. | [email protected] | 3.7 | 0.05% | 2026-05-25 | 2026-05-27 |
| CVE-2026-48851 | 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. | [email protected] | 3.1 | 0.03% | 2026-05-25 | 2026-05-27 |
| CVE-2026-48850 | PuTTY 0.72 before 0.84 has a double free in RSA KEX. | [email protected] | 3.7 | 0.06% | 2026-05-25 | 2026-05-27 |
| CVE-2026-4115 | 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 ident | [email protected] | 2.9 | 0.01% | 2026-03-22 | 2026-05-25 |
| CVE-2024-31497 | 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 a | [email protected] | 5.9 | 23.27% | 2024-04-15 | 2025-11-04 |
| CVE-2023-48795 | The SSH transport protocol with certain OpenSSH extensions, found in OpenSSH before 9.6 and other products, allows remote attackers to bypass integrity checks such that some packets are omitted (from the extension negotiation message), and a client and server may consequently end up with a connection for which some security features have been downgraded or disabled, aka a Terrapin attack. This occurs because the SSH Binary Packet Protocol (BPP), implemented by these extensions, mishandles the ha | [email protected] | 5.9 | 54.21% | 2023-12-18 | 2026-05-12 |
| CVE-2021-36367 | 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). | [email protected] | 8.1 | 0.14% | 2021-07-09 | 2024-11-21 |
| CVE-2021-33500 | 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. | [email protected] | 7.5 | 0.40% | 2021-05-21 | 2024-11-21 |
| CVE-2020-14002 | 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). | [email protected] | 5.9 | 0.75% | 2020-06-29 | 2024-11-21 |
| CVE-2019-17069 | 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. | [email protected] | 7.5 | 0.47% | 2019-10-01 | 2024-11-21 |
| CVE-2019-17068 | PuTTY before 0.73 mishandles the "bracketed paste mode" protection mechanism, which may allow a session to be affected by malicious clipboard content. | [email protected] | 7.5 | 0.37% | 2019-10-01 | 2024-11-21 |
| CVE-2019-17067 | 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. | [email protected] | 9.8 | 0.43% | 2019-10-01 | 2024-11-21 |
| CVE-2019-9898 | Potential recycling of random numbers used in cryptography exists within PuTTY before 0.71. | [email protected] | 9.8 | 4.29% | 2019-03-21 | 2024-11-21 |
| CVE-2019-9897 | Multiple denial-of-service attacks that can be triggered by writing to the terminal exist in PuTTY versions before 0.71. | [email protected] | 7.5 | 2.39% | 2019-03-21 | 2024-11-21 |
| CVE-2019-9896 | 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. | [email protected] | 7.8 | 2.24% | 2019-03-21 | 2024-11-21 |
| CVE-2019-9895 | In PuTTY versions before 0.71 on Unix, a remotely triggerable buffer overflow exists in any kind of server-to-client forwarding. | [email protected] | 9.8 | 1.37% | 2019-03-21 | 2024-11-21 |
| CVE-2019-9894 | A remotely triggerable memory overwrite in RSA key exchange in PuTTY before 0.71 can occur before host key verification. | [email protected] | 7.5 | 0.66% | 2019-03-21 | 2024-11-21 |
| CVE-2017-6542 | 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. | [email protected] | 9.8 | 30.63% | 2017-03-27 | 2026-05-13 |
| CVE-2016-6167 | 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. | [email protected] | 7.8 | 0.12% | 2017-01-30 | 2026-05-13 |
| CVE-2015-2157 | 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. | [email protected] | 2.1 | 0.09% | 2015-03-27 | 2026-05-06 |