CVE-2026-84894

HIGH
7.5
CVSS Score
Published: September 28, 2026 at 06:40 PM UTC
Updated: September 30, 2026 at 07:57 PM UTC
1 product affected across 1 vendorMoxygen

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Severity
HIGH7.5
Exploit prediction
EPSS 0.3%
SSVC
No known exploit

Description

In moxygen before commit 004123dd24c3, MoQSession::dataStreamReadLoop keeps using a stream read handle after reading a FIN, which invalidates the handle under proxygen's WebTransport API. A remote peer can trigger the stale use by opening a data stream that names an unknown track alias and carries the FIN in the same write.

Affected

Our own answer: ranges merged, affected separated from platform-only, with confidence and review flags.

b24f8e65cb83ebe5f3880cc4e3a4c8f64e1882f9 ≤ v < 004123dd24c30dad6b649163575145f240dabc94b24f8e65cb83ebe5f3880cc4e3a4c8f64e1882f9
Vendor states this is fixed in 004123dd24c30dad6b649163575145f240dabc94 (fixed)

Remediation

No guide yet

No remediation guidance has been written for this CVE yet, and no fixed version or vendor advisory is recorded against it.

SSVC — Action Prioritization

SSVCNo known exploitAutomatablePartial impact

SSVC signals action urgency (what to patch first), separate from CVSS which measures severity.

CVSS

7.5HIGHCISA-ADP
Attack Vector
NETWORK
Complexity
LOW
Privileges
NONE
User Interaction
NONE
Scope
UNCHANGED
Confidentiality
HIGH
Integrity
NONE
Availability
NONE
Vector?

Quick Info

StatusDEFERRED
CWE
CWE-416

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