How severe is CVE-2018-13347?

CVE-2018-13347 has a CVSS 3.x base score of 9.8, rated critical severity. It is exploitable over network with low attack complexity, requires no privileges and no user interaction. Impact on confidentiality is high, integrity high, and availability high.

Is CVE-2018-13347 being actively exploited?

It is not currently listed in CISA's KEV catalog. Its EPSS exploit-prediction score is 3% (84th percentile), an estimate of the probability of exploitation in the next 30 days.

What products are affected by CVE-2018-13347?

CVE-2018-13347 affects Mercurial. See the affected-products list for the exact vulnerable versions.

How do I fix CVE-2018-13347?

Review the linked vendor and NVD advisories for patched versions and mitigations, then upgrade or apply the recommended workaround. Given its critical severity, prioritise patching exposed systems.

When was CVE-2018-13347 published?

CVE-2018-13347 was published on 2018-07-06 and last updated on 2026-06-17.

CVE-2018-13347

CVE-2018-13347 is a critical-severity vulnerability in Mercurial with a CVSS 3.x base score of 9.8. It is not currently listed as actively exploited by CISA, and its EPSS exploit-prediction score is low. The underlying weakness is classified as CWE-190.

Key facts

Severity: Critical (CVSS 3.x base score 9.8)
CVSS v2: 7.5
EPSS exploit prediction: 3% (84th percentile)
Actively exploited: Not listed in CISA KEV
Weakness: CWE-190
Affected product: Mercurial
Published: 2018-07-06
Last modified: 2026-06-17

Description

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

Frequently asked questions

What is CVE-2018-13347?: mpatch.c in Mercurial before 4.6.1 mishandles integer addition and subtraction, aka OVE-20180430-0002.
How severe is CVE-2018-13347?: CVE-2018-13347 has a CVSS 3.x base score of 9.8, rated critical severity. It is exploitable over network with low attack complexity, requires no privileges and no user interaction. Impact on confidentiality is high, integrity high, and availability high.
Is CVE-2018-13347 being actively exploited?: It is not currently listed in CISA's KEV catalog. Its EPSS exploit-prediction score is 3% (84th percentile), an estimate of the probability of exploitation in the next 30 days.
What products are affected by CVE-2018-13347?: CVE-2018-13347 affects Mercurial. See the affected-products list for the exact vulnerable versions.
How do I fix CVE-2018-13347?: Review the linked vendor and NVD advisories for patched versions and mitigations, then upgrade or apply the recommended workaround. Given its critical severity, prioritise patching exposed systems.
When was CVE-2018-13347 published?: CVE-2018-13347 was published on 2018-07-06 and last updated on 2026-06-17.

References

Affected products (1)

cpe:2.3:a:mercurial:mercurial:*:*:*:*:*:*:*:*

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