CVE-2019-20633 — GNU patch through 2

GNU patch through 2.7.6 contains a free(p_line[p_end]) Double Free vulnerability in the function another_hunk in pch.c that can cause a denial of service via a crafted patch file. NOTE: this issue exists because of an incomplete fix for CVE-2018-6952.

01What is this vulnerability?

GNU patch through 2.7.6 contains a free(p_line[p_end]) Double Free vulnerability in the function another_hunk in pch.c that can cause a denial of service via a crafted patch file. NOTE: this issue exists because of an incomplete fix for CVE-2018-6952.

02Affected products

Vendor	Product	Versions
n	a / n/a	n/a

03Active exploitation status

Not currently listed on the CISA Known Exploited Vulnerabilities (KEV) catalog. EPSS is the best forward-looking signal — see the EPSS row above.

04Recommended remediation

• Patch to a fixed version listed in the vendor advisory (see references below).
• Mitigate with WAF rules, network egress filters, or feature flags where the patch is not yet available.
• Hunt historical logs for exploitation indicators — see Detection signatures below.

05Technical details

For the full vendor write-up, exploit chains, and reference implementations, see the references list in section 09.

06Detection signatures

Ask SARA in chat to draft a starting detection for this CVE in your stack of choice.

07Related CVEs

08Timeline

• Published: 2020-03-25T16:44:49.000Z
• Last modified: 2024-08-05T02:46:10.304Z

09References

• savannah.gnu.org — https://savannah.gnu.org/bugs/index.php?56683