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TI-2026-41066 Aliases CVE-2026-57076GHSA-q6x2-vfpr-9j7p

Use after free in TODDR YAML::Syck

Priority LOW 35CWE-416Published · Updated

Key facts

Attack vector
Local
Privileges required
Low
User interaction
None
Attack complexity
Low
Impact type
Code execution
Confidentiality · integrity · availability
High · High · High
Fix status
Partial Red Hat: 3 without a fix

Attack profile from CVSS 3.1 · CISA ADP. Fix status from CNA and Red Hat. Impact type from CWE-416 and the CVSS impact.

Summary

YAML::Syck versions before 1.47 for Perl allow a heap use-after-free via an anchor name reused as an anchors-table key in syck_hdlr_add_anchor. In the bundled libsyck an anchor name allocated by syck_strndup is stored both as node->anchor, freed when the node is freed, and as the key in the parser's anchors table. Freeing the node frees the shared key, and a later anchor redefinition makes st_delete compare against the freed key, so st_strcmp reads freed heap memory. Anchors are a standard YAML feature and need no special flags, so this is reached on the default Load path. Any caller that runs Load or LoadFile on an untrusted document that redefines an anchor reaches the read of freed memory.

Why it matters now

Exploitation None reported CISA SSVC · not in CISA KEV
EPSS 0.00168 6th percentileScored 2026-11-07
Fix Partial YAML::Syck (TODDR): 1.47Red Hat: 3 without a fix

SSVC decision points

CISA ADP · SSVC 2.0.3

Exploitation
None
Automatable
No
Technical impact
Total

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

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-2026-11561 Double free in TODDR YAML::SyckPriority LOW 27
    Show all 4 records →

Vendor assessments

Red Hat

Red Hat rating: Moderate. 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 8AffectedNo fix yet: Fix deferred

Timeline

  1. 2026-10-02 Threatist record created from CVE-2026-57076
  2. 2026-10-03 Alias added: GHSA-q6x2-vfpr-9j7p

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