SB2025101318 - Red Hat Enterprise Linux 9 update for gnutls
Published: October 13, 2025
Breakdown by Severity
- Low
- Medium
- High
- Critical
Description
This security bulletin contains information about 4 secuirty vulnerabilities.
1) NULL pointer dereference (CVE-ID: CVE-2025-32990)
The vulnerability allows a remote attacker to perform a denial of service (DoS) attack.
The vulnerability exists due to a NULL pointer dereference error when the certtool program is invoked with a template file with a number of string pairs for a single keyword. A remote attacker can pass specially crafted data to the application and perform a denial of service (DoS) attack.
2) Heap-based buffer overflow (CVE-ID: CVE-2025-32989)
The vulnerability allows a remote attacker to execute arbitrary code on the target system.
The vulnerability exists due to a boundary error when handling the Certificate Transparency (CT) Signed Certificate Timestamp (SCT) extension during X.509 certificate parsing. A remote attacker can supply a specially crafted X.509 certificate to the application, trigger a heap-based buffer overflow and execute arbitrary code on the target system.
Successful exploitation of this vulnerability may result in complete compromise of vulnerable system.
3) Double free (CVE-ID: CVE-2025-32988)
The vulnerability allows a remote attacker to execute arbitrary code on the target system.
The vulnerability exists due to a boundary error when exporting a certificate with an otherName in the SAN (subject alternative name) extension. A remote attacker can trick the victim into export a specially crafted certificate, trigger a double free error on the ASN.1 structure and execute arbitrary code on the target system.
Successful exploitation of this vulnerability may result in complete compromise of vulnerable system.
4) NULL pointer dereference (CVE-ID: CVE-2025-6395)
The vulnerability allows a remote attacker to perform a denial of service (DoS) attack.
The vulnerability exists due to a NULL pointer dereference error when a TLS 1.3 handshake involves a Hello Retry Request and the second Client Hello omits the PSK which was present in the first Client Hello. A remote attacker can pass specially crafted data to the application and perform a denial of service (DoS) attack.
Remediation
Install update from vendor's website.