CVE-2021-26813
HIGHEPSS 82th pctlDescription
markdown2 >=1.0.1.18, fixed in 2.4.0, is affected by a regular expression denial of service vulnerability. If an attacker provides a malicious string, it can make markdown2 processing difficult or delayed for an extended period of time.
How to fix
TridentStack Control can deploy fixes like this automatically across your Windows, macOS, and Linux fleet. See how it works
Remediation is compiled from vendor and distribution security advisories. Always confirm against the linked source for your exact version and platform.
CVSS v3 Vector
Exploitability
Impact
CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:H
Exploit Intelligence
Elevated risk: more likely to be exploited than 82% of all known CVEs.
References
Related Vulnerabilities
Other CWE-1333 vulnerabilities, ordered by exploit likelihood. View all
| CVE | Severity | CVSS | EPSS | Exploited | Fix |
|---|---|---|---|---|---|
| CVE-2023-3364 | High | 7.5 | 44% | - | Fix |
| CVE-2024-8124 | High | 7.5 | 40% | - | Fix |
| CVE-2024-25126 | Medium | 5.3 | 35% | - | Fix |
| CVE-2024-2651 | Medium | 6.5 | 33% | - | Fix |
| CVE-2021-32837 | High | 7.5 | 29% | - | Fix |
| CVE-2024-2829 | High | 7.5 | 26% | - | Fix |
Common questions
How do I fix CVE-2021-26813?
Upgrade python-markdown2 on debian 11 to 2.3.10-1.1 or later.
Is CVE-2021-26813 being actively exploited?
Not that we know of. CVE-2021-26813 is not in the CISA Known Exploited Vulnerabilities catalog. Its EPSS score of 2.4% is the estimated probability that it will be exploited in the next 30 days. That is higher than 82% of all scored CVEs.
How severe is CVE-2021-26813?
CVE-2021-26813 has a CVSS v3 base score of 7.5, rated high. CVSS rates the technical impact if the vulnerability is exploited, not how likely that is, so weigh it alongside the exploit-prediction score when you decide what to patch first.
What does CVE-2021-26813 affect?
Published advisories record a fix for python-markdown2 (Debian). Only products with a sourced advisory are listed, so treat this as what we can cite rather than a complete inventory.
Embed a live status badge for CVE-2021-26813
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This product uses NVD data but is not endorsed or certified by the NVD. EPSS scores courtesy of FIRST.org (https://www.first.org/epss). Source: CISA KEV Catalog. Data as of 2024-11-21.