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% (85th 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% (85th 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% (85th 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:*:*:*:*:*:*:*:*

More vulnerabilities in Gnu Patch

CVE-2019-13638 — High (CVSS 7.8): GNU patch through 2.7.6 is vulnerable to OS shell command injection that can be exploited by opening a crafted patch…
CVE-2018-1000156 — High (CVSS 7.8): GNU Patch version 2.7.6 contains an input validation vulnerability when processing patch files, specifically the…
CVE-2015-1396 — High (CVSS 7.5): A Directory Traversal vulnerability exists in the GNU patch before 2.7.4. A remote attacker can write to arbitrary…
CVE-2018-6952 — High (CVSS 7.5): A double free exists in the another_hunk function in pch.c in GNU patch through 2.7.6.
CVE-2018-6951 — High (CVSS 7.5): An issue was discovered in GNU patch through 2.7.6. There is a segmentation fault, associated with a NULL pointer…
CVE-2015-1395 — High (CVSS 7.5): Directory traversal vulnerability in GNU patch versions which support Git-style patching before 2.7.3 allows remote…

All CVEs affecting Gnu Patch →

Other CWE-78 (OS Command Injection) vulnerabilities

CVE-2026-19188 — Critical (CVSS 10.0): A critical OS command injection vulnerability has been identified in the Haiwell IoT Cloud HMI Gateway product. The…
CVE-2026-48362 — Critical (CVSS 10.0): ColdFusion is affected by an Improper Neutralization of Special Elements used in an OS Command ('OS Command Injection')…
CVE-2026-16812 — Critical (CVSS 10.0): VeloCloud Orchestrator (VCO) on-prem has a security issue where this issue may allow a remote attacker to access…
CVE-2026-6516 — Critical (CVSS 10.0): Zohocorp ManageEngine ADAudit Plus versions before 8606 are affected by Unauthenticated Remote code execution due to…
CVE-2026-46339 — Critical (CVSS 10.0): 9Router is an AI router & token saver. From 0.4.30 until 0.4.37, 9Router's src/proxy.js middleware did not protect…
CVE-2026-59726 — Critical (CVSS 10.0): Ruflo is an agent meta-harness for Claude Code and Codex. Prior to 3.16.3, ruflo's default docker-compose deployment…

Browse all CWE-78 (OS Command Injection) vulnerabilities →