Improper input validation in Github Cmark-Gfm

CVE-2020-5238

The table extension in GitHub Flavored Markdown before version 0.29.0.gfm.1 takes O(n * n) time to parse certain inputs. An attacker could craft a markdown table which would take an unreasonably long time to process, causing a denial of service. This issue does not affect the upstream cmark project. The issue has been fixed in version 0.29.0.gfm.1.

Vulnerability class: Drupalgeddon 2 (CVE-2018-7600)

EPSS: 0.016 (72.8th percentile) — read the EPSS interpretation.

CVSS v3 metric

CVSS v3 base score 6.5 (Medium). Vector: CVSS:3.1/AV:N/AC:L/PR:L/UI:N/S:U/C:N/I:N/A:H.

Affected products

Weakness classification (CWE)

References

Frequently asked questions

What is CVE-2020-5238?
CVE-2020-5238 is a medium-severity vulnerability in Github Cmark-Gfm, classified under Improper Input Validation. CVSS score: 6.5/10. Published 2020-07-01.
How severe is CVE-2020-5238?
Medium severity. CVSS v3 base score is 6.5 out of 10.