What is CVE-2023-33981?

CVE-2023-33981 is a medium-severity vulnerability in Briarproject Briar, classified under Improper Validation of Integrity Check Value. CVSS score: 6.5/10. Published 2023-05-24.

How severe is CVE-2023-33981?

Medium severity. CVSS v3 base score is 6.5 out of 10.

Vulnerability in Briarproject Briar

CVE-2023-33981

Briar before 1.4.22 allows attackers to spoof other users' messages in a blog, forum, or private group, but each spoofed message would need to be an exact duplicate of a legitimate message displayed alongside the spoofed one.

Published 2023-05-24 · last modified 2026-06-17.

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:H/A:N.

EPSS exploit prediction

EPSS: 0.003 (24.4th percentile), scored 2026-10-02.

Very low probability of exploitation in the next 30 days; routine patching cadence is appropriate. 24th percentile — 24.4% of CVEs in the catalogue have a lower EPSS than this one. How to read EPSS.

EPSS over last 30 days · oldest: 0.003 · newest: 0.003 · change: 0.000

Affected products

Briarproject Briar

Weakness classification (CWE)

CWE-354 — Improper Validation of Integrity Check Value

References

briarproject.org/news/2023-three-security-issues-found-and-fixed/ (Vendor Advisory)
ethz.ch/content/dam/ethz/special-interest/infk/inst-infsec/appliedcrypto/educat… (Technical Description, Exploit, Third Party Advisory)

Frequently asked questions

What is CVE-2023-33981?: CVE-2023-33981 is a medium-severity vulnerability in Briarproject Briar, classified under Improper Validation of Integrity Check Value. CVSS score: 6.5/10. Published 2023-05-24.
How severe is CVE-2023-33981?: Medium severity. CVSS v3 base score is 6.5 out of 10.