SECURELYN
Free ScanFree consultation

CVE-2026-102560

A flaw was found in libsoup. When the permessage-deflate WebSocket extension compresses a very large outgoing message, truncated size calculations used for GByteArray growth could wrap, causing zlib to write past the allocated buffer and resulting in a heap buffer overflow.

Scores

9.8
CVSS 9.8 out of 10, critical severity.
0.4%
EPSS 0.4% chance of exploitation in the next 30 days.

The facts

Published
29 September 2026
Last changed
16 October 2026
NVD status
Analyzed
Severity
Critical, CVSS 9.8 out of 10 (version 3.1)
CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:H/A:H
Weakness
Affects
  • gnome libsoup
  • redhat enterprise linux
Known exploited
Not in the CISA Known Exploited Vulnerabilities catalogue in this build.
EPSS
0.4% chance of exploitation activity in the next 30 days (percentile 35).

Is there a Securelyn advisory?

Not yet. Securelyn writes plain-English advisories for the flaws that matter most to businesses. Subscribe to the digest to hear about them.

References