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TI-2026-60128 Aliases CVE-2026-88359GHSA-3qj9-89fg-m5cw

libfyaml 0.9.6 contains a stack exhaustion vulnerability in fy_atom_iter_format().

Priority MEDIUM 62CWE-770Published · Updated

Key facts

Attack vector
Network
Privileges required
None
User interaction
Required
Attack complexity
Low
Impact type
Denial of service
Confidentiality · integrity · availability
None · None · High
Fix status
No fix listed

Attack profile from CVSS 3.1 · CISA ADP. Fix status from CNA. Impact type from CWE-770.

Summary

libfyaml 0.9.6 contains a stack exhaustion vulnerability in fy_atom_iter_format(). When processing a specially crafted YAML document containing a very large literal or folded block scalar, the function repeatedly grows an internal buffer using alloca() inside a loop. The allocated stack memory is not released until the function returns, causing cumulative stack growth that can exceed the process stack limit and result in SIGSEGV and denial of service.

Why it matters now

Exploitation Proof of concept CISA SSVC · not in CISA KEV
EPSS 0.00296 22nd percentileScored 2026-11-07
Fix No fix listed No fixed version in the sources yet

SSVC decision points

CISA ADP · SSVC 2.0.3

Exploitation
Poc
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
——all versions—No fix listedCNA
  • — Vendor— Affected all versions Fixed in — No fix listed CNA

Remediation

No fixed version listed by the sources yet.

Vendor assessments

Red Hat

Red Hat's page for this CVE →

Not affected: 1 product
  • Red Hat

Timeline

  1. 2026-10-02 Threatist record created from CVE-2026-88359
  2. 2026-10-03 Alias added: GHSA-3qj9-89fg-m5cw

References

Other 3

Sources

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