CVE-2021-26813
CVSS v3
7.5
HIGH
EPSS Score
2.2 %
exploit probability, as of 2026-09-25
CISA KEV
No
known exploited
Exploitation
—
SSVC status
Description
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.
Technical details
- Published
- 2021-03-03
Frequently asked questions
What is CVE-2021-26813?
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.
Is CVE-2021-26813 actively exploited?
Active exploitation of CVE-2021-26813 has not been confirmed. Its EPSS score was 2.2% on 2026-09-25, the estimated probability of exploitation in the next 30 days.
What is the CVSS score for CVE-2021-26813?
CVE-2021-26813 has a CVSS v3 base score of 7.5 (HIGH severity).
Is CVE-2021-26813 affecting your environment?
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