YAML::Syck versions before 1.47 for Perl allow a use-after-free and double-free via an anchor...
Summary
Vulnerability reported (CVE-2026-13713). Risk of unauthorized operations or information disclosure.
Original description
The description as published by the source.
YAML::Syck versions before 1.47 for Perl allow a use-after-free and double-free via an anchor node freed while still on the parser value stack.
In the bundled libsyck, when an anchor name is redefined or removed, syck_hdlr_add_anchor and syck_hdlr_remove_anchor free the node stored under that name with syck_free_node. That node can still be live on the parser's value stack, so syck_hdlr_add_node reaches it again and frees it a second time. On a normal build the 48-byte node chunk is freed twice and the interpreter aborts. Anchors need no special flags, so this is reached on the default Load path, and a 7-byte document that redefines an anchor triggers it.
Any caller that runs Load or LoadFile on an untrusted document that redefines an anchor mid-parse crashes the interpreter, a denial of service.
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-2026-13713 has been found.
Risk of unauthorized operations or information disclosure. CVSS score: 6.2/10.
What to do: apply the vendor's official patched release.
If unsure, ask your IT team or search "CVE-2026-13713" on the vendor's site.
CVE-2026-13713 — CWE-415 / CVSS v3 6.2
Attack vector: local / 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-415) has been reported.
Check the vendor advisory for the affected versions.
Severity: Medium (CVSS 6.2/10). 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. 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。
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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
- Alpine Linux ALPINE-CVE-2026-13713 perl-yaml-syck Fixed in: 1.47-r0
- BellSoft Alpaquita BELL-CVE-2026-13713 perl-yaml-syck Fixed in: 1.34-r5
- Debian DEBIAN-CVE-2026-13713 libyaml-syck-perl Fixed in: 1.34-2+deb12u3
- Ubuntu UBUNTU-CVE-2026-13713 libyaml-syck-perl
References
- web github.com
- web metacpan.org
- web nvd.nist.gov
- web github.com
- web openwall.com