YAML::Syck versions before 1.38 for Perl has an out-of-bounds read. The base60 (sexagesimal)...
Summary
Vulnerability reported (CVE-2026-5089). Risk of unauthorized operations or information disclosure.
Original description
The description as published by the source.
YAML::Syck versions before 1.38 for Perl has an out-of-bounds read.
The base60 (sexagesimal) parsing code in perl_syck.h has a buffer underflow bug in both int#base60 and float#base60 handlers. When processing the leftmost segment of a colon-separated value (e.g., the 1 in 1:30:45), the inner while loop can decrement a pointer past the start of the string buffer:
while ( colon >= ptr && *colon != ':' )
{
colon--;
}
if ( *colon == ':' ) *colon = '\0'; // colon may be ptr-1 here
When no colon is found (final/leftmost segment), colon becomes ptr-1, and the subsequent *colon dereference reads one byte before the allocated buffer.
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-2026-5089 has been found.
Risk of unauthorized operations or information disclosure. CVSS score: 7.3/10.
What to do: apply the vendor's official patched release.
If unsure, ask your IT team or search "CVE-2026-5089" on the vendor's site.
CVE-2026-5089 — CWE-124 / CVSS v3 7.3
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) has been reported.
Check the vendor advisory for the affected versions.
Severity: High (CVSS 7.3/10). 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. Audit SBOM/dependencies to find affected services.
Response actions
Concrete steps and command examples for SOC/SRE teams to execute in order
-
1Identify exposure identify
Audit SBOM/dependencies for affected components.資産台帳・SBOM・依存マニフェストで影響コンポーネントを特定する。
-
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
- BellSoft Alpaquita BELL-CVE-2026-5089 perl-yaml-syck Fixed in: 1.34-r4
- Debian DEBIAN-CVE-2026-5089 libyaml-syck-perl
- Ubuntu UBUNTU-CVE-2026-5089 libyaml-syck-perl
References
- web github.com
- web github.com
- web github.com
- web metacpan.org
- web nvd.nist.gov
- web github.com
- web openwall.com