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TI-2026-11561 Aliases CVE-2026-13713GHSA-p3p9-6pr6-mr9m

Double free in TODDR YAML::Syck

Priority LOW 27CWE-415Published · Updated

Key facts

Attack vector
Local
Privileges required
None
User interaction
None
Attack complexity
Low
Impact type
Denial of service
Confidentiality · integrity · availability
None · None · High
Fix status
Partial Red Hat: 1 fixed, 2 without a fix

Attack profile from CVSS 3.1 · CISA ADP. Fix status from CNA and Red Hat. Impact type from CWE-415 and the CVSS impact.

Summary

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.

Why it matters now

Exploitation None reported CISA SSVC · not in CISA KEV
EPSS 0.00179 7th percentileScored 2026-11-07
Fix Partial YAML::Syck (TODDR): 1.47Red Hat: 1 advisoryRed Hat: 1 fixed, 2 without a fix

SSVC decision points

CISA ADP · SSVC 2.0.3

Exploitation
None
Automatable
No
Technical impact
Partial

The decision (Track, Attend, Act) also depends on your mission and well-being impact; see CISA's SSVC guide.

Affected products

VendorProductAffected versionsFixed inStatusSource
TODDRYAML::Syckbefore 1.471.47Patch availableCNA
  • YAML::Syck VendorTODDR Affected before 1.47 Fixed in 1.47 Patch available CNA

Remediation

  • Fix · CNA YAML::Syck (TODDR) Fixed in 1.47

Red Hat 1 advisory

  • RHSA-2026:67269 Released 2026-09-14 · Red Hat rating Important
    perl-YAML-Syck security update
    • Red Hat Enterprise Linux CRB (v. 8) perl-YAML-Syck-1.30-7.el8_10

Fixed in the same release

Records fixed by the same vendor advisory or release, as the CNA lists them.

  • Release ·

    TODDR YAML::Syck 1.47

    4 records Highest priority Priority MEDIUM 1 MEDIUM, 3 LOW

    Other records, highest priority first

    • TI-2026-41065 Out-of-bounds read in TODDR YAML::SyckPriority MEDIUM 48
    • TI-2026-41067 Out-of-bounds read in TODDR YAML::SyckPriority LOW 35
    • TI-2026-41066 Use after free in TODDR YAML::SyckPriority LOW 35
    Show all 4 records →

Vendor assessments

Red Hat

Red Hat rating: Important. Red Hat's page for this CVE →

ProductStatusPlan or fix
Red Hat Enterprise Linux 6AffectedNo fix planned: Out of support scope
Red Hat Enterprise Linux 7AffectedNo fix planned: Out of support scope
Red Hat Enterprise Linux CRB (v. 8)Fixed RHSA-2026:67269

Timeline

  1. 2026-10-02 Threatist record created from CVE-2026-13713
  2. 2026-10-03 Alias added: GHSA-p3p9-6pr6-mr9m

References

Patch 1

Other 1

  • TI-2026-04444 YAML::Syck versions before 1.38 for Perl has an out-of-bounds read CVSS 3.1HIGH 7.3
  • TI-2006-06994 Heap-based buffer overflow in TODDR XML::Parser CVSS 3.1CRITICAL 9.8
  • TI-2006-06993 Heap-based buffer overflow in TODDR XML::Parser CVSS 3.1CRITICAL 9.8
  • TI-2026-41065 Out-of-bounds read in TODDR YAML::Syck CVSS 3.1CRITICAL 9.1
  • TI-2026-03625 Heap-based buffer overflow in TODDR YAML::Syck CVSS 3.1CRITICAL 9.1
  • TI-2026-41067 Out-of-bounds read in TODDR YAML::Syck CVSS 3.1HIGH 7.7
See all 8 →

Sources

This product uses the NVD API but is not endorsed or certified by the NVD. Sources and licences