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 to determine the victim's private key) can derive the victim's private key, and then use it for unauthorized access to those other services. If the other services include Git services, then again it may be possible to conduct supply-chain attacks on software maintained in Git. This also affects, for example, FileZilla before 3.67.0, WinSCP before 6.3.3, TortoiseGit before 2.15.0.1, and TortoiseSVN through 1.14.6.
References
Link Providers
http://www.openwall.com/lists/oss-security/2024/04/15/6 cve-icon cve-icon cve-icon
https://bugzilla.redhat.com/show_bug.cgi?id=2275183 cve-icon cve-icon cve-icon
https://bugzilla.suse.com/show_bug.cgi?id=1222864 cve-icon cve-icon cve-icon
https://docs.ccv.brown.edu/oscar/connecting-to-oscar/ssh/ssh-agent-forwarding/key-generation-and-agent-forwarding-with-putty cve-icon cve-icon cve-icon
https://filezilla-project.org/versions.php cve-icon cve-icon cve-icon
https://git.tartarus.org/?h=c193fe9848f50a88a4089aac647fecc31ae96d27&p=simon/putty.git cve-icon cve-icon cve-icon
https://github.com/advisories/GHSA-6p4c-r453-8743 cve-icon cve-icon cve-icon
https://github.com/daedalus/BreakingECDSAwithLLL cve-icon cve-icon cve-icon
https://lists.debian.org/debian-lts-announce/2024/06/msg00014.html cve-icon cve-icon cve-icon
https://lists.fedoraproject.org/archives/list/package-announce%40lists.fedoraproject.org/message/IZS3B37GNGWOOV7QU7B7JFK76U4TOP4V/ cve-icon cve-icon cve-icon
https://lists.fedoraproject.org/archives/list/package-announce%40lists.fedoraproject.org/message/MMHILY2K7HQGQRHOC375KRRG2M6625RD/ cve-icon cve-icon cve-icon
https://lists.fedoraproject.org/archives/list/package-announce%40lists.fedoraproject.org/message/PUOTQVGC4DISVHQGSPUYGXO6TLDK65LA/ cve-icon cve-icon cve-icon
https://lists.fedoraproject.org/archives/list/package-announce%40lists.fedoraproject.org/message/WFDZBV7ZCAZ6AH3VCQ34SSY7L3J7VZXZ/ cve-icon cve-icon cve-icon
https://lists.fedoraproject.org/archives/list/package-announce%40lists.fedoraproject.org/message/WMJH7M663BVO3SY6MFAW2FAZWLLXAPRQ/ cve-icon cve-icon cve-icon
https://news.ycombinator.com/item?id=40044665 cve-icon cve-icon cve-icon
https://security-tracker.debian.org/tracker/CVE-2024-31497 cve-icon cve-icon cve-icon
https://securityonline.info/cve-2024-31497-critical-putty-vulnerability-exposes-private-keys-immediate-action-required/ cve-icon cve-icon cve-icon
https://tartarus.org/~simon/putty-snapshots/htmldoc/Chapter9.html#pageant-forward cve-icon cve-icon cve-icon
https://tortoisegit.org cve-icon cve-icon cve-icon
https://twitter.com/CCBalert/status/1780229237569470549 cve-icon cve-icon cve-icon
https://twitter.com/lambdafu/status/1779969509522133272 cve-icon cve-icon cve-icon
https://winscp.net/eng/news.php cve-icon cve-icon cve-icon
https://www.bleepingcomputer.com/news/security/putty-ssh-client-flaw-allows-recovery-of-cryptographic-private-keys/ cve-icon cve-icon cve-icon
https://www.chiark.greenend.org.uk/~sgtatham/putty/changes.html cve-icon cve-icon cve-icon
https://www.chiark.greenend.org.uk/~sgtatham/putty/wishlist/vuln-p521-bias.html cve-icon cve-icon cve-icon
https://www.openwall.com/lists/oss-security/2024/04/15/6 cve-icon cve-icon cve-icon
https://www.reddit.com/r/sysadmin/comments/1c4wmoj/putty_vulnerability_affecting_v068_to_v08/ cve-icon cve-icon cve-icon
https://www.vicarius.io/vsociety/posts/understanding-a-critical-vulnerability-in-putty-biased-ecdsa-nonce-generation-revealing-nist-p-521-private-keys-cve-2024-31497 cve-icon cve-icon
History

Mon, 19 Aug 2024 08:30:00 +0000

Type Values Removed Values Added
CPEs cpe:2.3:a:putty:putty:-:*:*:*:*:*:*:*
References
Metrics ssvc

{'options': {'Automatable': 'No', 'Exploitation': 'None', 'Technical Impact': 'Partial'}, 'version': '2.0.3'}


cve-icon MITRE

Status: PUBLISHED

Assigner: mitre

Published: 2024-04-15T00:00:00

Updated: 2024-08-19T07:48:01.287Z

Reserved: 2024-04-04T00:00:00

Link: CVE-2024-31497

cve-icon Vulnrichment

Updated: 2024-08-19T07:48:01.287Z

cve-icon NVD

Status : Modified

Published: 2024-04-15T20:15:11.077

Modified: 2024-11-21T09:13:38.997

Link: CVE-2024-31497

cve-icon Redhat

No data.