What is CVE-2017-8399?

CVE-2017-8399 is a critical-severity vulnerability in Pcre Pcre2, classified under Improper Restriction of Operations within the Bounds of a Memory Buffer. CVSS score: 9.8/10. Published 2017-05-01.

How severe is CVE-2017-8399?

Critical severity. CVSS v3 base score is 9.8 out of 10.

Buffer overflow in Pcre Pcre2

CVE-2017-8399

PCRE2 before 10.30 has an out-of-bounds write caused by a stack-based buffer overflow in pcre2_match.c, related to a "pattern with very many captures."

Vulnerability class: Buffer Overflow

Published 2017-05-01 · last modified 2026-06-17.

CVSS v3 metric

CVSS v3 base score 9.8 (Critical). Vector: CVSS:3.0/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:H/A:H.

EPSS exploit prediction

EPSS: 0.031 (87.7th percentile), scored 2026-10-26.

Low probability of exploitation in the next 30 days, but still tracked. 88th percentile — 87.7% of CVEs in the catalogue have a lower EPSS than this one. How to read EPSS.

EPSS over last 30 days · oldest: 0.031 · newest: 0.031 · change: 0.000

Affected products

Pcre Pcre2

Weakness classification (CWE)

CWE-119 — Improper Restriction of Operations within the Bounds of a Memory Buffer

References

security.gentoo.org/glsa/201710-09 (vendor-advisory, Third Party Advisory)
vcs.pcre.org/pcre2/code/tags/pcre2-10.30/ChangeLog
bugs.chromium.org/p/oss-fuzz/issues/detail (Third Party Advisory)
vcs.pcre.org/pcre2 (Patch, Vendor Advisory)
www.securityfocus.com/bid/98315 (VDB Entry, Third Party Advisory, vdb-entry)

Frequently asked questions

What is CVE-2017-8399?: CVE-2017-8399 is a critical-severity vulnerability in Pcre Pcre2, classified under Improper Restriction of Operations within the Bounds of a Memory Buffer. CVSS score: 9.8/10. Published 2017-05-01.
How severe is CVE-2017-8399?: Critical severity. CVSS v3 base score is 9.8 out of 10.