How severe is CVE-2018-13346?

CVE-2018-13346 has a CVSS 3.x base score of 7.5, rated high severity. It is exploitable over network with low attack complexity, requires no privileges and no user interaction. Impact on confidentiality is none, integrity high, and availability none.

Is CVE-2018-13346 being actively exploited?

It is not currently listed in CISA's KEV catalog. Its EPSS exploit-prediction score is 2% (82nd percentile), an estimate of the probability of exploitation in the next 30 days.

What products are affected by CVE-2018-13346?

CVE-2018-13346 affects Mercurial. See the affected-products list for the exact vulnerable versions.

How do I fix CVE-2018-13346?

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

When was CVE-2018-13346 published?

CVE-2018-13346 was published on 2018-07-06 and last updated on 2026-06-17.

CVE-2018-13346

CVE-2018-13346 is a high-severity vulnerability in Mercurial with a CVSS 3.x base score of 7.5. 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-20.

Key facts

Severity: High (CVSS 3.x base score 7.5)
CVSS v2: 5.0
EPSS exploit prediction: 2% (82nd percentile)
Actively exploited: Not listed in CISA KEV
Weakness: CWE-20
Affected product: Mercurial
Published: 2018-07-06
Last modified: 2026-06-17

Description

The mpatch_apply function in mpatch.c in Mercurial before 4.6.1 incorrectly proceeds in cases where the fragment start is past the end of the original data, aka OVE-20180430-0004.

Frequently asked questions

What is CVE-2018-13346?: The mpatch_apply function in mpatch.c in Mercurial before 4.6.1 incorrectly proceeds in cases where the fragment start is past the end of the original data, aka OVE-20180430-0004.
How severe is CVE-2018-13346?: CVE-2018-13346 has a CVSS 3.x base score of 7.5, rated high severity. It is exploitable over network with low attack complexity, requires no privileges and no user interaction. Impact on confidentiality is none, integrity high, and availability none.
Is CVE-2018-13346 being actively exploited?: It is not currently listed in CISA's KEV catalog. Its EPSS exploit-prediction score is 2% (82nd percentile), an estimate of the probability of exploitation in the next 30 days.
What products are affected by CVE-2018-13346?: CVE-2018-13346 affects Mercurial. See the affected-products list for the exact vulnerable versions.
How do I fix CVE-2018-13346?: Review the linked vendor and NVD advisories for patched versions and mitigations, then upgrade or apply the recommended workaround. Given its high severity, prioritise patching exposed systems.
When was CVE-2018-13346 published?: CVE-2018-13346 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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