A flaw was found in libsoup. When constructing a masked WebSocket client frame for a very large outgoing payload, size values passed to GByteArray allocation APIs could be truncated while the masking routine still used the full length, causing a heap buffer overflow.
Fix
Patch, vendor advisory and mitigation references on NVD 2
- https://access.redhat.com/security/cve/CVE-2026-102559 Mitigation, Third Party Advisory
- https://bugzilla.redhat.com/show_bug.cgi?id=2543285 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 6
- References+1 references (now 5)NVD modified 2026-10-19 05:17
- StatusAnalyzed → ModifiedNVD modified 2026-10-19 05:17
- Cpes+5 CPE criteria (now 5)NVD modified 2026-10-16 14:06
- StatusUndergoing Analysis → AnalyzedNVD modified 2026-10-16 14:06
- 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 5
- 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/errata/RHSA-2026:84586
- https://access.redhat.com/security/cve/CVE-2026-102559 Mitigation, Third Party Advisory
- https://bugzilla.redhat.com/show_bug.cgi?id=2543285 Issue Tracking, Patch, Third Party Advisory