Vulnerability in Libssh (CVE-2026-0966)
Summary
Vulnerability in Libssh (CVE-2026-0966). Risk of unauthorized operations or information disclosure.
Original description
The description as published by the source.
A flaw was found in libssh. The API function ssh_get_hexa() is vulnerable to a denial of service when processing zero-length input. This can be exploited remotely by an attacker during GSSAPI (Generic Security Service Application Program Interface) authentication if the server's logging verbosity is set to SSH_LOG_PACKET (3) or higher. Successful exploitation could lead to a self-Denial of Service of the per-connection daemon process.
Source: NIST National Vulnerability Database NVD GitHub Advisory
Auto-generated summary
Assembled by SecPulse from the source data (CVSS, CWE, affected versions) using templates — no AI involved. Check the original description and references below for exact details.
A vulnerability tracked as CVE-2026-0966 has been found in Libssh.
Risk of unauthorized operations or information disclosure. CVSS score: 8.2/10.
What to do: apply the vendor's official patched release.
If unsure, ask your IT team or search "Libssh CVE-2026-0966" on the vendor's site.
CVE-2026-0966 (Libssh) — CWE-124 / CVSS v3 8.2
Attack vector: remote (network-reachable) / unauthenticated / no user interaction
Plan: 1) Audit SBOM/dependencies, 2) Stage→prod upgrade, 3) Add WAF/proxy monitoring on affected endpoints, 4) Hunt IOCs in logs.
Refs: see the GHSA / vendor advisory / patched release linked on this page.
A vulnerability (CWE-124) exists in Libssh.
Check the vendor advisory for the affected versions of Libssh.
Severity: High (CVSS 8.2/10). Risk of unauthorized operations or information disclosure.
Update to the patched release per vendor advisory.
Until the patch is applied: disable the affected feature, apply WAF rules, or restrict access via network ACLs.
Search webserver/proxy logs for unusual request patterns matching this CVE's known IOCs. Run grep -r 'Libssh' . against your dependency files (package-lock.json, requirements.txt, go.sum) to find affected services.
Response actions
Concrete steps and command examples for SOC/SRE teams to execute in order
-
1Identify exposure identify
grep -r 'Libssh' . | grep -v node_modulesリポジトリと本番環境の依存ファイル (package-lock.json / requirements.txt / go.sum / Gemfile.lock 等) で
Libsshを grep し、稼働しているサービス・バージョンを把握する。 -
2Post-deployment verification verify
Confirm patched version is live in productionパッチ適用後、ステージングで PoC または同等の悪用パターンを再現して脆弱性が閉じたことを確認。本番ではアクセスログ・WAF でアラート再発が無いか継続監視。
Fix status by distribution
Fixed packages published by each distribution for this CVE
- Debian DEBIAN-CVE-2026-0966 libssh
- Ubuntu UBUNTU-CVE-2026-0966 libssh Fixed in: 0.6.3-4.3ubuntu0.6+esm4
References
- advisory access.redhat.com
- advisory access.redhat.com
- advisory access.redhat.com
- advisory nvd.nist.gov
- advisory access.redhat.com
- advisory github.com
- report bugzilla.redhat.com
- web libssh.org
- web libssh.org
- web github.com
- web access.redhat.com
- web catalog.redhat.com