Low
tinyssh — security advisory
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.
- Products
- tinyssh
- Affected versions
- 20180101-1, 20180201-1, 20190101-1build1, 20190101-1ubuntu1, 20230101-2, 20230101-3, 20230101-4, 20240101-1, 20240101-2, 20250201-1, 20250501-1, 20250501-2, 20260601-1
- Fixed versions
- Not specified
- CVEs
- CVE-2026-4541
- Confirmed fixed CVEs
- Not specified
- Updated in this feed
- 31 Oct 2026, 02:14 UTC · Revision 1
Source evidence
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.
osv:UBUNTU-CVE-2026-4541
tinyssh
Fixed versions: Not specified
tinyssh
Fixed versions: Not specified
tinyssh
Fixed versions: Not specified
tinyssh
Fixed versions: Not specified
tinyssh
Fixed versions: Not specified
tinyssh
Fixed versions: Not specified
tinyssh
Fixed versions: Not specified
Complete source record
{
"id": "3592c6a3c3cfc1c5b1aefa2dfe4e40d6072b14ba3cf30c9b161cfec6bc8f8110",
"url": "https://osv.dev/vulnerability/UBUNTU-CVE-2026-4541",
"method": "structured",
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"summary": "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.",
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"modified": "2026-10-17T12:58:23.055964745Z",
"provider": "osv",
"upstream": [
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"references": [
"https://ubuntu.com/security/CVE-2026-4541",
"https://www.cve.org/CVERecord?id=CVE-2026-4541",
"https://github.com/janmojzis/tinyssh/",
"https://github.com/janmojzis/tinyssh/commit/9c87269607e0d7d20174df742accc49c042cff17",
"https://github.com/janmojzis/tinyssh/issues/101",
"https://github.com/janmojzis/tinyssh/issues/101#issue-3983586116",
"https://github.com/janmojzis/tinyssh/pull/102",
"https://github.com/janmojzis/tinyssh/releases/tag/20260301",
"https://vuldb.com/?ctiid.352358",
"https://vuldb.com/?id.352358",
"https://vuldb.com/?submit.774687"
]
},
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"source_id": "core-osv",
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"published_at": "2026-03-22T09:15:00+00:00"
}