{"id":"CVE-2026-102559","title":"A flaw was found in libsoup","summary":"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, c…","severity":"high","cvss":8.6,"cvssVector":"CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:L/I:L/A:H","cwe":["CWE-125"],"vendor":"Red Hat","product":"libsoup3","affected":["libsoup3 (all versions)","libsoup (all versions)","libsoup","libsoup (all versions)","libsoup (all versions)"],"published":"2026-09-29","updated":"2026-10-15","sourceUpdated":"2026-10-15T17:17:09.633","source":"NVD","sourceUrl":"https://nvd.nist.gov/vuln/detail/CVE-2026-102559","references":[{"url":"https://access.redhat.com/errata/RHSA-2026:83384","label":"secalert@redhat.com"},{"url":"https://access.redhat.com/errata/RHSA-2026:83618","label":"secalert@redhat.com"},{"url":"https://access.redhat.com/security/cve/CVE-2026-102559","label":"secalert@redhat.com"},{"url":"https://bugzilla.redhat.com/show_bug.cgi?id=2543285","label":"secalert@redhat.com"},{"url":"https://security.access.redhat.com/data/csaf/v2/vex/2026/cve-2026-102559.json"},{"url":"https://www.cve.org/CVERecord?id=CVE-2026-102559"},{"url":"https://nvd.nist.gov/vuln/detail/CVE-2026-102559"},{"url":"https://access.redhat.com/errata/RHSA-2026:84586","label":"RHSA-2026:84586"},{"url":"https://access.redhat.com/errata/RHSA-2026:92347","label":"RHSA-2026:92347"}],"tags":["nvd","cve.org","csaf","vex","red-hat"],"ssvc":{"exploitation":"none","automatable":"yes","technicalImpact":"partial","timestamp":"2026-09-30T19:42:40.159345Z"},"epss":0.00404,"epssPercentile":0.34438,"ingestedAt":"2026-09-29T17:41:02.260Z","patched":["enterprise_linux_appstream_v_10","enterprise_linux_appstream_v_8","enterprise_linux_appstream_v_9","enterprise_linux_baseos_v_8","enterprise_linux_codeready_linux_builder_v_10"],"slug":"CVE-2026-102559","body":"## Overview\n\nA 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.\n\n## Remediation\n\nRefer to the linked advisories for vendor-supplied fixes and affected version ranges.\n\n## Vendor advisories\n\n- **Red Hat VEX** · Important · affected: Red Hat Enterprise Linux 6, Red Hat Enterprise Linux 7 · no fix planned: Red Hat Enterprise Linux 6, Red Hat Enterprise Linux 7 · updated 2026-10-19 · [vex](https://security.access.redhat.com/data/csaf/v2/vex/2026/cve-2026-102559.json)\n- **RHSA-2026:83618** · Red Hat · fixed in: Red Hat Enterprise Linux AppStream (v. 10), Red Hat Enterprise Linux CodeReady Linux Builder (v. 10) · released 2026-10-15 · [advisory](https://access.redhat.com/errata/RHSA-2026:83618)\n- **RHSA-2026:84586** · Red Hat · fixed in: Red Hat Enterprise Linux AppStream (v. 8), Red Hat Enterprise Linux BaseOS (v. 8) · released 2026-10-19 · [advisory](https://access.redhat.com/errata/RHSA-2026:84586)\n- **RHSA-2026:83384** · Red Hat · fixed in: Red Hat Enterprise Linux AppStream (v. 9) · released 2026-10-15 · [advisory](https://access.redhat.com/errata/RHSA-2026:83384)","depth":"twilight","depthScore":47,"depthScoreParts":{"impact":47.3,"likelihood":0.1,"exploitation":0,"ransomware":0},"changes":[]}