CVE-2021-24029

7.5 highEPSS 1.2%

High (7.5) in facebook. EPSS 1.2% chance of exploitation in the next 30 days.

A packet of death scenario is possible in mvfst via a specially crafted message during a QUIC session, which causes a crash via a failed assertion. Per QUIC specification, this particular message should be treated as a connection error. This issue affects mvfst versions prior to commit a67083ff4b8dcbb7ee2839da6338032030d712b0 and proxygen versions prior to v2021.03.15.00.

Severity

CVSS 3.1

7.5 high

CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:H

EPSS: 1.2% chance of exploitation in the next 30 days; higher than 67% of CVEs (scores of 2026-10-31)
CWE: CWE-617
Published: 2021-03-15
Modified: 2026-06-17
Record from: the NVD, synced 2026-10-19

Affected

facebook:mvfst
facebook:proxygen

References

https://github.com/facebookincubator/mvfst/commit/a67083ff4b8dcbb7ee2839da6338032030d712b0
https://www.facebook.com/security/advisories/cve-2021-24029
https://github.com/facebookincubator/mvfst/commit/a67083ff4b8dcbb7ee2839da6338032030d712b0
https://www.facebook.com/security/advisories/cve-2021-24029

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