CVE-2026-85534
MEDIUM
MEDIUM
Priority: 0.02
BB Relevance:
62/100
Published: 2026-09-04
Modified: 2026-11-06
First seen: 2026-11-06
Status: active
Attack Surface
Network
No Auth
No Interaction
CVSS Vector Breakdown
AV:
Network
AC:
High
PR:
None
UI:
None
S:
Unchanged
C:
None
I:
None
A:
High
Description
A flaw was found in libsoup. When a client sends an HTTP/2 request body from a non-pollable input stream, the library can buffer more data than the current flow-control window later allows. A malicious HTTP/2 server can shrink SETTINGS_INITIAL_WINDOW_SIZE while that buffered read is still in progress. The client then copies the full buffer into a smaller DATA callback without a runtime bounds check, which can abort the process or fail the HTTP/2 session.