CVE-2026-85534
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.
Published:Sep 3, 2026
Last Modified:Sep 4, 2026
EPS:Sep 4, 2026
EPSS Score:
CVSS Score:5.9
Affected Products
Vendor
Product
Action
Vendor
Gnome
Product
Libsoup
Gnome
Libsoup
Vendor
Redhat
Product
Enterprise Linux
Redhat
Enterprise Linux
Exploits
No exploit reference
Common Weakness Enumeration
Common Attack Pattern Enumeration and Classification (CAPEC)
No CAPEC recorded yet
Related CVEs
Common Vulnerability Scoring System
Attack Vector
Network
Adjacent
Local
Physical
Privileges Required
None
Low
High
User Interaction
None
Required
Scope
Unchanged
Changed
Confidentiality
None
Low
High
Integrity
None
Low
High
Availability
None
Low
High
