Affected: libgnutls, Red Hat Enterprise Linux 10, Red Hat Enterprise Linux 9, Red Hat Enterprise Linux 9.2 Update Services for SAP Solutions, Red Hat Enterprise Linux 9.4 Extended Update Support, Red Hat Ceph Storage 7, Red Hat Discovery 2, Red Hat Hardened Images, Red Hat Insights proxy 1.5, Red Hat Enterprise Linux 6 and 6 more

A heap-buffer-overread vulnerability was found in GnuTLS in how it handles the Certificate Transparency (CT) Signed Certificate Timestamp (SCT) extension during X.509 certificate parsing. This flaw allows a malicious user to create a certificate containing a malformed SCT extension (OID 1.3.6.1.4.1.11129.2.4.2) that contains sensitive data. This issue leads to the exposure of confidential information when GnuTLS verifies certificates from certain websites when the certificate (SCT) is not checked correctly.

Affected: Ubuntu:22.04:LTS: gnutls28, Ubuntu:24.04:LTS: gnutls28

It was discovered that GnuTLS incorrectly handled exporting Subject Alternative Name (SAN) entries containing an otherName. A remote attacker could use this issue to cause GnuTLS to crash, resulting in a denial of service, or possibly execute arbitrary code. (CVE-2025-32988)

It was discovered that GnuTLS incorrectly handled parsing the Certificate Transparency (CT) Signed Certificate Timestamp (SCT) extension. A remote attacker could use this issue to cause GnuTLS to crash, resulting in a denial of service, or possibly obtain sensitive information. (CVE-2025-32989)

It was discovered that the GnuTLS certtool utility incorrectly handled parsing certain template files. An attacker could use this issue to cause GnuTLS to crash, resulting in a denial of service, or possibly execute arbitrary code. (CVE-2025-32990)

Stefan Bühler discovered that GnuTLS incorrectly handled parsing certain template files. An attacker could possibly use this issue to cause GnuTLS to crash, resulting in a denial of service. (CVE-2025-6395)