CVE-2021-3403
CVSS v3
7.8
HIGH
EPSS Score
1.8 %
exploit probability, as of 2026-09-25
CISA KEV
No
known exploited
Exploitation
—
SSVC status
Description
In ytnef 1.9.3, the TNEFSubjectHandler function in lib/ytnef.c allows remote attackers to cause a denial-of-service (and potentially code execution) due to a double free which can be triggered via a crafted file.
Technical details
- Published
- 2021-03-04
Frequently asked questions
What is CVE-2021-3403?
In ytnef 1.9.3, the TNEFSubjectHandler function in lib/ytnef.c allows remote attackers to cause a denial-of-service (and potentially code execution) due to a double free which can be triggered via a crafted file.
Is CVE-2021-3403 actively exploited?
Active exploitation of CVE-2021-3403 has not been confirmed. Its EPSS score was 1.8% on 2026-09-25, the estimated probability of exploitation in the next 30 days.
What is the CVSS score for CVE-2021-3403?
CVE-2021-3403 has a CVSS v3 base score of 7.8 (HIGH severity).
Is CVE-2021-3403 affecting your environment?
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