SB2026100854 - Red Hat Enterprise Linux 8 update for bind
Published: October 8, 2026
Breakdown by Severity
- Low
- Medium
- High
- Critical
Description
This security bulletin contains information about 3 vulnerabilities.
1) Numeric Truncation Error (CVE-ID: CVE-2026-19667)
CWE-ID: CWE-197 - Numeric Truncation Error
CVSSv4: 8.7 [CVSS:4.0/AV:N/AC:L/AT:N/PR:N/UI:N/VC:N/VI:N/VA:H/SC:N/SI:N/SA:N]
The vulnerability allows a remote attacker to cause a denial of service.
The vulnerability exists due to numeric truncation in dns_ncache_add() when processing a negative answer exactly 65536 bytes long from an attacker-controlled authoritative server. A remote attacker can return such a negative answer to cause a denial of service.
2) Input validation error (CVE-ID: CVE-2026-80274)
CWE-ID: CWE-20 - Improper input validation
CVSSv4: 8.7 [CVSS:4.0/AV:N/AC:L/AT:N/PR:N/UI:N/VC:N/VI:N/VA:H/SC:N/SI:N/SA:N]
The vulnerability allows a remote attacker to cause a denial of service.
The vulnerability exists due to improper validation of a NOQNAME proof in the BIND validating resolver when processing DNSSEC responses. A remote attacker can send a DNS response containing a valid wildcard answer and signed NSEC3 proof followed by an unsigned NSEC record at the same owner name to cause a denial of service.
The resolver must query a DNSSEC-signed authoritative zone.
3) Use-after-free (CVE-ID: CVE-2026-19666)
CWE-ID: CWE-416 - Use After Free
CVSSv4: 8.7 [CVSS:4.0/AV:N/AC:L/AT:N/PR:N/UI:N/VC:N/VI:N/VA:H/SC:N/SI:N/SA:N]
The vulnerability allows a remote attacker to cause a denial of service.
The vulnerability exists due to use-after-free in query_addnoqnameproof() via the DNS64 filter64 path when processing a malformed applicable answer from an authoritative server. A remote attacker can send a malformed applicable DNS answer to cause a denial of service.
Only resolvers configured to use dns64 are affected.
Remediation
Install update from vendor's website.