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TI-2026-85465 Aliases CVE-2026-107891GHSA-mr8f-pr8h-27pc

Integer overflows in musl libc regcomp allow heap out-of-bounds writes

Priority LOW 36CWE-190Published · Updated

Key facts

Attack vector
Network
Privileges required
None
User interaction
None
Attack complexity
High
Impact type
Code execution
Confidentiality · integrity · availability
High · High · High
Fix status
Fixed

Attack profile from CVSS 3.1 · CNA. Fix status from CNA. Impact type from CWE-190 and the CVSS impact.

Summary

musl libc from 0.5.0 before 1.2.7 has multiple integer overflows in regcomp when an untrusted regular expression is compiled. The overflows can lead to incorrect allocation sizes and out-of-bounds heap writes (CWE-190). An attacker who can supply a regular expression to an application that calls regcomp may be able to corrupt heap memory.

Written with Claude Haiku 5.5 from the sources below · 2026-11-06

Description from the CNA

musl libc before 1.2.7, when an untrusted regular expression is used with regcomp, has multiple integer overflows, possibly leading to incorrect allocation sizes and out-of-bounds heap writes.

Why it matters now

EPSS 0.00549 46th percentileScored 2026-11-07
Fix Fixed musl (musl -libc): 1.2.7

SSVC decision points

Not available: CISA has not published SSVC decision points for this record.

Affected products

VendorProductAffected versionsFixed inStatusSource
musl-libcmusl0.5.0 to before 1.2.71.2.7Patch availableCNA
  • musl Vendormusl-libc Affected 0.5.0 to before 1.2.7 Fixed in 1.2.7 Patch available CNA

Remediation

Upgrade musl to version 1.2.7, which fixes the flaw.

Written with Claude Haiku 5.5 from the sources below · 2026-11-06

  • Fix · CNA musl (musl -libc) Fixed in 1.2.7

Vendor assessments

Red Hat

Red Hat's page for this CVE →

Not affected: 1 product
  • Red Hat

Timeline

  1. 2026-11-05 Threatist record created from CVE-2026-107891
  2. 2026-11-05 Alias added: GHSA-mr8f-pr8h-27pc
  3. 2026-11-06 Affected versions changed · Red Hat
  4. 2026-11-06 CVSS score added · Red Hat
  5. 2026-11-07 Priority changed: MEDIUM → LOW

References

Other 3

  • TI-2019-10919 musl libc through 1.1.23 has an x87 floating-point stack adjustment imbalance, related to… CVSS 3.1CRITICAL 9.8
  • TI-2015-01634 Stack-based buffer overflow in the inet_pton function in network/inet_pton.c in musl libc… CVSS 3.0CRITICAL 9.8
  • TI-2014-02811 Out-of-bounds write in musl libc CVSS 3.1CRITICAL 9.8
  • TI-2025-19457 Out-of-bounds write in musl-libc musl CVSS 3.1HIGH 8.1
  • TI-2017-11441 musl libc before 1.1.17 has a buffer overflow via crafted DNS replies because… CVSS 3.0HIGH 7.5
  • TI-2026-29014 An issue was discovered in musl libc 0.7.10 through 1.2.6. CVSS 3.1HIGH 8.1
See all 7 →

Sources

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