SB2026103003 - Red Hat Enterprise Linux 8 update for pcre2
Published: October 30, 2026
Breakdown by Severity
- Low
- Medium
- High
- Critical
Description
This security bulletin contains information about 2 vulnerabilities.
1) Heap-based buffer overflow (CVE-ID: CVE-2026-86145)
CWE-ID: CWE-122 - Heap-based Buffer Overflow
CVSSv4: 8.8 [CVSS:4.0/AV:N/AC:L/AT:N/PR:N/UI:N/VC:N/VI:H/VA:L/SC:N/SI:N/SA:N]
The vulnerability allows a remote attacker to cause a denial of service.
The vulnerability exists due to heap-based buffer overflow in pcre2_dfa_match() when processing an attacker-supplied regular expression with recursive patterns under a low heap limit. A remote attacker can supply a specially crafted regular expression to cause a denial of service.
Exploitation requires the application to use DFA matching, and the heap limit can be lowered within the pattern using the (*LIMIT_HEAP=...) control verb. Control of the subject or match context is not required.
2) Out-of-bounds write (CVE-ID: CVE-2026-103111)
CWE-ID: CWE-787 - Out-of-bounds write
CVSSv4: 7.2 [CVSS:4.0/AV:N/AC:L/AT:N/PR:L/UI:N/VC:L/VI:H/VA:L/SC:N/SI:N/SA:N]
The vulnerability allows a remote user to corrupt adjacent memory.
The vulnerability exists due to an out-of-bounds write in JIT matching stack allocation handling when matching a JIT-compiled user-supplied regular expression requiring a large single stack allocation. A remote user can supply a regular expression with many capturing groups and recursive matching to corrupt adjacent memory.
Only applications with JIT enabled that create and assign a growable JIT stack are affected.
Remediation
Install update from vendor's website.