Heap-based buffer overflow in PCRE2 - CVE-2026-86145

Vulnerability identifier: #VU146524

CSH Severity: High

CVSS v4: 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]

CVE-ID: CVE-2026-86145

CWE-ID: CWE-122

Exploitation vector: Remote access

Exploit availability: No public exploit available

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.

PCRE2
Red Hat Enterprise Linux Server - AUS
openEuler
Anolis OS
pcre2 (Red Hat package)
pcre2-help
pcre2-devel
pcre2-debugsource
pcre2-debuginfo
pcre2
pcre2-syntax
pcre2-utf32
pcre2-utf16
pcre2-tools
pcre2-static

Install security update from vendor's website.

PCRE2 - update to 10.48
pcre2 (Red Hat package) - addressed in versions 10.32-2.el8_4.1, 10.32-3.el8_6.1
pcre2-help - addressed in versions 10.35-12, 10.39-19, 10.42-15
pcre2-devel - addressed in versions 10.35-12, 10.39-19, 10.42-15
pcre2-debugsource - addressed in versions 10.35-12, 10.39-19, 10.42-15
pcre2-debuginfo - addressed in versions 10.35-12, 10.39-19, 10.42-15
pcre2 - addressed in versions 10.35-12, 10.39-19, 10.42-15
pcre2-syntax - update to 10.42-5
pcre2-utf32 - update to 10.42-5
pcre2-utf16 - update to 10.42-5
pcre2-tools - update to 10.42-5
pcre2-static - update to 10.42-5
pcre2-devel - update to 10.42-5
pcre2 - update to 10.42-5

• https://github.com/PCRE2Project/pcre2/security/advisories/GHSA-3r4p-g7gg-ppmf
• https://github.com/PCRE2Project/pcre2/commit/3979bb90cc692a371d33e6b159dc324f27361deb

• Multiple vulnerabilities in PCRE2
• openEuler 24.03 LTS SP4 update for pcre2
• openEuler 24.03 LTS SP1 update for pcre2
• openEuler 22.03 LTS SP4 update for pcre2
• openEuler 20.03 LTS SP4 update for pcre2
• Anolis OS update for pcre2
• Red Hat Enterprise Linux 8 update for pcre2
• Red Hat Enterprise Linux 8 update for pcre2