What’s Vulnerable › Vulnerabilities

CVE-2026-84895

• Severity: high (CVSS 7.3 v3.1)
• Exploited in the wild: not listed in CISA KEV
• EPSS: 0.2% probability of exploitation in the next 30 days
• Public exploit or detection template: none known
• Published: 2026-09-28 · updated 2026-10-01
• Weakness: CWE-416

Description

In proxygen from v2026.04.06.00 until v2026.09.28.00, QuicWtSession::closeSession accesses its member fields after calling the base QuicWtSessionBase::closeSession method. The base method notifies the session handler, which may release the last reference to the session and destroy it.

Affected products

• Facebook proxygen: from v2026.04.06.00 before v2026.09.28.00 — fixed in v2026.09.28.00

How to fix

Upgrade to a fixed version: Facebook proxygen v2026.09.28.00. Check the vendor advisory for mitigations.

References

• https://github.com/facebook/proxygen/commit/479eb5574195764e80e6cedebef669f6baa85083
• https://www.facebook.com/security/advisories/cve-2026-84895

Get alerted when CVE-2026-84895 or the next vulnerability affects your stack