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.
Fix
Patch, vendor advisory and mitigation references on NVD 2
- https://access.redhat.com/security/cve/CVE-2026-102560 Mitigation, Third Party Advisory
- https://bugzilla.redhat.com/show_bug.cgi?id=2543296 Issue Tracking, Patch, Third Party Advisory
Every line above is quoted from NVD, CISA, Microsoft, the vendor's own advisory or DISA; nothing is generated.
Change history 5
- Cpes+5 CPE criteria (now 5)NVD modified 2026-10-16 13:56
- StatusUndergoing Analysis → AnalyzedNVD modified 2026-10-16 13:56
- CVSS8.6 (v3.1, CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:L/I:L/A:H) → 9.8 (v3.1, CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:H/A:H)NVD modified 2026-10-16 13:56
- References+1 references (now 4)NVD modified 2026-10-15 17:17
- First seenCVSS 8.6NVD modified 2026-10-15 06:17
Affected (CPE criteria) 5
cpe:2.3:a:gnome:libsoup:*:*:*:*:*:*:*:*cpe:2.3:o:redhat:enterprise_linux:7.0:*:*:*:*:*:*:*cpe:2.3:o:redhat:enterprise_linux:8.0:*:*:*:*:*:*:*cpe:2.3:o:redhat:enterprise_linux:9.0:*:*:*:*:*:*:*cpe:2.3:o:redhat:enterprise_linux:10.0:*:*:*:*:*:*:*
References 4
- https://access.redhat.com/errata/RHSA-2026:83384 Third Party Advisory
- https://access.redhat.com/errata/RHSA-2026:83618 Third Party Advisory
- https://access.redhat.com/security/cve/CVE-2026-102560 Mitigation, Third Party Advisory
- https://bugzilla.redhat.com/show_bug.cgi?id=2543296 Issue Tracking, Patch, Third Party Advisory