SB2026092604 - Red Hat Enterprise Linux 7 Extended Lifecycle Support update for unbound
Published: September 26, 2026
Security Bulletin ID
SB2026092604
CSH Severity
High
Patch available
YES
Number of vulnerabilities
1
Exploitation vector
Remote access
Highest impact
Code execution
Breakdown by Severity
- Low
- Medium
- High
- Critical
Description
This security bulletin contains information about 1 vulnerability.
1) Out-of-bounds write (CVE-ID: CVE-2026-81642)
CWE-ID: CWE-787 - Out-of-bounds write
CVSSv4: 9.3 [CVSS:4.0/AV:N/AC:L/AT:N/PR:N/UI:N/VC:H/VI:H/VA:H/SC:N/SI:N/SA:N]
The vulnerability allows a remote attacker to execute arbitrary code or cause a denial of service.
The vulnerability exists due to a buffer overflow in Unbound's DNSSEC validator when processing a DNSKEY with an owner compression pointer to its own RDATA. A remote attacker can control a malicious zone and query a vulnerable Unbound instance to execute arbitrary code or cause a denial of service.
Remediation
Install update from vendor's website.