Junglewise Threat Intelligence

CVE-2025-32988: GnuTLS double-free in Subject Alternative Name export logic

CVE-2025-32988 · Severity: medium · CVSS 6.5 · Published 2025-07-10

Technologies: Red Hat Enterprise Linux 9, Red Hat Enterprise Linux 8, Red Hat Enterprise Linux 10, GnuTLS Project Gnutls. Vendors: Red Hat.

Executive brief

GnuTLS is a widely used security library that enables encrypted communications for websites and applications. A flaw in how it handles certain certificate data could allow an attacker to crash services or potentially corrupt system memory. This could lead to a service outage or provide a foothold for further malicious activity.

Technical details

A double-free vulnerability exists in GnuTLS due to incorrect ownership handling in the export logic of Subject Alternative Name (SAN) entries containing an 'otherName'. When a malformed or invalid type-id OID is encountered, GnuTLS incorrectly calls asn1_delete_structure() on an ASN.1 node it does not own. This results in a double-free condition when the caller subsequently attempts to free the same structure. The flaw can be triggered via public GnuTLS APIs, and while it primarily results in a denial of service (crash), it may lead to memory corruption depending on the system's memory allocator behavior. The issue is resolved in GnuTLS version 3.8.10 and various vendor-specific patches.

Affected products

  • GnuTLS Project GnuTLS < 3.8.10
  • Red Hat Red Hat Enterprise Linux 8 < 3.6.16-8.el8_10.4
  • Red Hat Red Hat Enterprise Linux 9 < 3.8.3-6.el9_6.2
  • Red Hat Red Hat Enterprise Linux 10 < 3.8.9-9.el10_0.14

Timeline

  • 2025-07-08: patched: GnuTLS 3.8.10 released with fix
  • 2025-07-10: disclosed: CVE-2025-32988 published
  • 2025-09-17: advisory: Red Hat issued security advisories RHSA-2025:16115 and RHSA-2025:16116

References

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