CVE-2026-121737
Deferred Deferred - Pending Action

HTTP/1.1 Request Pipelining DoS in Proxygen

Vulnerability report for CVE-2026-121737, including description, CVSS score, EPSS score, affected products, exploitability, helpful resources, and attack-flow context.

Publication date: 2026-11-11

Last updated on: 2026-11-11

Assigner: Facebook, Inc.

Description

When a remote, unauthenticated HTTP/1.1 client pipelined the start of a second request and then stopped reading, proxygen's coroutine-based HTTP session could free that pipelined stream while resetting the connection's streams on the resulting write timeout, then go on to use it. This can crash the server, leading to denial of service, and may allow memory corruption with further impact. This issue affects proxygen versions prior to v2026.11.09.00.

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Meta Information

Published
2026-11-11
Last Modified
2026-11-11
Generated
2026-11-11
EPSS Evaluated
N/A
NVD
EUVD

Affected Vendors & Products

Showing 1 associated CPE
Vendor Product Version / Range
facebook proxygen to 2026.11.09.00 (exc)

Helpful Resources

Exploitability

CWE
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CWE ID Description
CWE-UNKNOWN

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