CVE-2026-4541

Name	CVE-2026-4541
Description	A flaw has been found in janmojzis tinyssh up to 20250501. Impacted is an unknown function of the file tinyssh/crypto_sign_ed25519_tinyssh.c of the component Ed25519 Signature Handler. This manipulation causes improper verification of cryptographic signature. The attack is restricted to local execution. The attack's complexity is rated as high. The exploitability is considered difficult. The exploit has been published and may be used. Upgrading to version 20260301 is recommended to address this issue. Patch name: 9c87269607e0d7d20174df742accc49c042cff17. Upgrading the affected component is recommended. If you want to get best quality of vulnerability data, you may have to visit VulDB.
Source	CVE (at NVD; CERT, ENISA, LWN, oss-sec, fulldisc, Debian ELTS, Red Hat, Ubuntu, Gentoo, SUSE bugzilla/CVE, GitHub advisories/code/issues, web search, more)

Vulnerable and fixed packages

The table below lists information on source packages.

Source Package	Release	Version	Status
tinyssh (PTS)	bullseye	20190101-1+deb11u1	fixed
	bookworm	20230101-1	fixed
	trixie	20250501-1	vulnerable
	forky, sid	20260301-1	fixed

The information below is based on the following data on fixed versions.

Package	Type	Release	Fixed Version	Urgency
tinyssh	source	bullseye	(not affected)
tinyssh	source	bookworm	(not affected)
tinyssh	source	(unstable)	20260301-1	unimportant

Notes

[bookworm] - tinyssh <not-affected> (Vulnerable code not present)
[bullseye] - tinyssh <not-affected> (Vulnerable code not present)
https://github.com/janmojzis/tinyssh/issues/101
https://github.com/janmojzis/tinyssh/pull/102
Fixed by: https://github.com/janmojzis/tinyssh/commit/9c87269607e0d7d20174df742accc49c042cff17 (20260301)
Negligible security impact