CVE-2026-12478
Publication date 14 July 2026
Last updated 16 July 2026
Ubuntu priority
Description
The fix for CVE-2026-0716 (commit 6ff7ef0, libsoup 3.6.6) placed the integer overflow guard inside the if (masked) block, leaving unmasked server-to-client frames unprotected. A malicious WebSocket server can send a crafted unmasked frame with a payload length near UINT64_MAX to trigger an OOB read in a libsoup-based client when max_incoming_payload_size is set to 0.
Status
| Package | Ubuntu Release | Status |
|---|---|---|
| libsoup3 | 26.04 LTS resolute |
Needs evaluation
|
| 24.04 LTS noble |
Needs evaluation
|
|
| 22.04 LTS jammy |
Needs evaluation
|
Severity score breakdown
CVSS version: CVSS v3.0
Base score
4.8 · Medium
Vector: CVSS:3.1/AV:N/AC:H/PR:N/UI:N/S:U/C:L/I:N/A:L