CVE-2021-4156
CVSS v3
7.1
HIGH
EPSS Score
1.8 %
exploit probability, as of 2026-09-25
CISA KEV
No
known exploited
Exploitation
—
SSVC status
Description
An out-of-bounds read flaw was found in libsndfile's FLAC codec functionality. An attacker who is able to submit a specially crafted file (via tricking a user to open or otherwise) to an application linked with libsndfile and using the FLAC codec, could trigger an out-of-bounds read that would most likely cause a crash but could potentially leak memory information that could be used in further exploitation of other flaws.
Technical details
- Published
- 2022-03-23
Frequently asked questions
What is CVE-2021-4156?
An out-of-bounds read flaw was found in libsndfile's FLAC codec functionality. An attacker who is able to submit a specially crafted file (via tricking a user to open or otherwise) to an application linked with libsndfile and using the FLAC codec, could trigger an out-of-bounds read that would most likely cause a crash but could potentially leak memory information that could be used in further exploitation of other flaws.
Is CVE-2021-4156 actively exploited?
Active exploitation of CVE-2021-4156 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-2021-4156?
CVE-2021-4156 has a CVSS v3 base score of 7.1 (HIGH severity).
Is CVE-2021-4156 affecting your environment?
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