What is CVE-2018-13347?

CVE-2018-13347 is a critical-severity vulnerability in Mercurial, classified under Integer Overflow or Wraparound. CVSS score: 9.8/10. Published 2018-07-06.

How severe is CVE-2018-13347?

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

Integer overflow in Mercurial

CVE-2018-13347

mpatch.c in Mercurial before 4.6.1 mishandles integer addition and subtraction, aka OVE-20180430-0002.

Vulnerability class: Integer Overflow

Published 2018-07-06 · 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: 0.027 (85.2th percentile), scored 2026-09-29.

Low probability of exploitation in the next 30 days, but still tracked. 85th percentile — 85.2% of CVEs in the catalogue have a lower EPSS than this one. How to read EPSS.

EPSS over last 30 days · oldest: 0.027 · newest: 0.027 · change: 0.000

Affected products

Mercurial

Weakness classification (CWE)

CWE-190 — Integer Overflow or Wraparound

References

www.mercurial-scm.org/repo/hg-committed/log (Patch, Vendor Advisory)
www.mercurial-scm.org/wiki/WhatsNew (Release Notes, Vendor Advisory)
www.mercurial-scm.org/repo/hg/rev/1acfc35d478c (Patch, Vendor Advisory)
access.redhat.com/errata/RHSA-2019:2276 (vendor-advisory)
lists.debian.org/debian-lts-announce/2020/07/msg00032.html (mailing-list)

Frequently asked questions

What is CVE-2018-13347?: CVE-2018-13347 is a critical-severity vulnerability in Mercurial, classified under Integer Overflow or Wraparound. CVSS score: 9.8/10. Published 2018-07-06.
How severe is CVE-2018-13347?: Critical severity. CVSS v3 base score is 9.8 out of 10.