How severe is CVE-2018-20969?

CVE-2018-20969 has a CVSS 3.x base score of 7.8, rated high severity. It is exploitable over local access with low attack complexity, requires no privileges and user interaction. Impact on confidentiality is high, integrity high, and availability high.

Is CVE-2018-20969 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-2018-20969?

CVE-2018-20969 affects Gnu Patch. See the affected-products list for the exact vulnerable versions.

How do I fix CVE-2018-20969?

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-2018-20969 published?

CVE-2018-20969 was published on 2019-08-16 and last updated on 2026-06-17.

CVE-2018-20969

CVE-2018-20969 is a high-severity vulnerability in Gnu Patch with a CVSS 3.x base score of 7.8. 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-78.

Key facts

Severity: High (CVSS 3.x base score 7.8)
CVSS v2: 9.3
EPSS exploit prediction: 3% (84th percentile)
Actively exploited: Not listed in CISA KEV
Weakness: CWE-78
Affected product: Gnu Patch
Published: 2019-08-16
Last modified: 2026-06-17

Description

do_ed_script in pch.c in GNU patch through 2.7.6 does not block strings beginning with a ! character. NOTE: this is the same commit as for CVE-2019-13638, but the ! syntax is specific to ed, and is unrelated to a shell metacharacter.

Frequently asked questions

What is CVE-2018-20969?: do_ed_script in pch.c in GNU patch through 2.7.6 does not block strings beginning with a ! character. NOTE: this is the same commit as for CVE-2019-13638, but the ! syntax is specific to ed, and is unrelated to a shell metacharacter.
How severe is CVE-2018-20969?: CVE-2018-20969 has a CVSS 3.x base score of 7.8, rated high severity. It is exploitable over local access with low attack complexity, requires no privileges and user interaction. Impact on confidentiality is high, integrity high, and availability high.
Is CVE-2018-20969 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-2018-20969?: CVE-2018-20969 affects Gnu Patch. See the affected-products list for the exact vulnerable versions.
How do I fix CVE-2018-20969?: 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-2018-20969 published?: CVE-2018-20969 was published on 2019-08-16 and last updated on 2026-06-17.

References

Affected products (1)

cpe:2.3:a:gnu:patch:*:*:*:*:*:*:*:*

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