CVE-2021-24029CWE-617

CVE-2021-24029: vulnerability in Facebook mvfst

Published · Updated

Follow this CVE+ Monitor Proxygen+ Monitor mvfst

E-mail alert when it lands in KEV, gets a public PoC or its score goes up.

3Vexday Risk Score

No sign of exploitation. No public exploitation artifact known so far.

ssvc Trackepss 1.2%
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.
Affected products
Facebook · mvfstFacebook · proxygen
Related CVEs — Facebook mvfst

In the same product, most dangerous first.

CVE-2020-1897—CVE-2020-1897EPSS 1.1%CVE-2026-44909HIGHCVE-2026-44909EPSS 0.6%CVE-2025-30403HIGHCVE-2025-30403EPSS 0.3%CVE-2025-55181MEDIUMCVE-2025-55181EPSS 0.3%CVE-2026-91096HIGHCVE-2026-91096EPSS 0.3%CVE-2026-91095MEDIUMCVE-2026-91095EPSS 0.2%