Vulnerability · Published Sep 18, 2026 · Assigned by GitHub_M
CVE-2026-77396PJSIP: Heap buffer overflow in the AVI parser
Medium 6.9
In plain English
A medium-severity heap buffer overflow in pjproject from pjsip. There are no confirmed reports of exploitation so far. The chance it is exploited in the next 30 days is estimated at 0.1% (higher than 2% of all known vulnerabilities). Ready-made attack tooling exists: public proof-of-concept code.
Official description
PJSIP is a free and open source multimedia communication library written in C. In 2.17 and earlier, the PJSIP AVI parser in pjmedia/src/pjmedia/avi_player.c uses an input-file video chunk length as the number of bytes copied into a frame buffer whose capacity is derived from the declared media dimensions. A crafted AVI file can therefore cause an attacker-controlled out-of-bounds write past the heap allocation when an application plays the file or pulls its frames. The existing size assertion does not protect production release builds, where assertions are disabled. Typical local playback can crash the process, while applications that accept untrusted AVI sources expose a stronger memory-corruption condition. No fixed version is available as of this review.
Affected packages & fixed versions
| Ecosystem | Package | Fixed in | Advisory |
|---|---|---|---|
| Debian:14 | asterisk | no fix listed | DEBIAN-CVE-2026-77396 |
| Ubuntu:22.04:LTS | asterisk | no fix listed | UBUNTU-CVE-2026-77396 |
| Ubuntu:24.04:LTS | asterisk | no fix listed | UBUNTU-CVE-2026-77396 |
| Ubuntu:26.04:LTS | asterisk | no fix listed | UBUNTU-CVE-2026-77396 |
| Ubuntu:26.10 | asterisk | no fix listed | UBUNTU-CVE-2026-77396 |
Affected products (as reported)
Weakness: CWE-122, CWE-787 · Vector: CVSS:4.0/AV:L/AC:L/AT:N/PR:N/UI:P/VC:N/VI:H/VA:H/SC:N/SI:N/SA:N