CVE-2026-4115

Name
CVE-2026-4115
Description
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.
NVD Severity
unknown
Other trackers
Mailing lists
Exploits
Forges
GitHub (code, issues), Aports (code, issues)

References

Type URI
cna@vuldb.com https://git.tartarus.org/?p=simon/putty.git;a=commitdiff;h=af996b5ec27ab79bae3882071b9d6acf16044549
cna@vuldb.com https://github.com/py-thok/putty-ed25519-malleability-s-plus-l
cna@vuldb.com https://github.com/py-thok/putty-ed25519-malleability-s-plus-l/blob/main/poc.py
cna@vuldb.com https://vuldb.com/?ctiid.352429
cna@vuldb.com https://vuldb.com/?id.352429
cna@vuldb.com https://vuldb.com/?submit.775576
cna@vuldb.com https://www.chiark.greenend.org.uk/~sgtatham/putty/wishlist/eddsa-overlarge-s.html
cna@vuldb.com https://www.rfc-editor.org/rfc/rfc8032#section-8.4

Match rules

CPE URI Source package Min version Max version
cpe:2.3:a:putty:putty:0.83:*:*:*:*:*:*:* putty == None == 0.83

Vulnerable and fixed packages

Source package Branch Version Maintainer Status
putty edge-community 0.83-r2 None possibly vulnerable
putty edge-community 0.83-r1 Celeste <cielesti@protonmail.com> possibly vulnerable
putty edge-community 0.83-r0 Celeste <cielesti@protonmail.com> possibly vulnerable
putty 3.23-community 0.83-r1 Celeste <cielesti@protonmail.com> possibly vulnerable