# CVE-2026-53702: Gstreamer1-plugins-bad-free: gstreamer: stack buffer overflow in h.265 buffering period sei parser

> A stack buffer overflow in the GStreamer H.265 parser allows attackers to cause crashes or execute code via crafted video files.

- **Severity:** Medium 6.5 (`CVSS:3.1/AV:N/AC:L/PR:N/UI:R/S:U/C:N/I:N/A:H`)
- **Exploited in the wild:** Not known
- **Login needed:** Not needed
- **Attackable:** Over the internet
- **Victim action needed:** A user has to click or open something
- **Fix available:** Yes
- **Published:** 11 Jun 2026
- **Updated:** 15 Jun 2026
- **Also known as:** DEBIAN-CVE-2026-53702, ECHO-1c25-a74a-9071, GHSA-gmqw-mqj2-6j9j, OESA-2026-2793, UBUNTU-CVE-2026-53702

## What is CVE-2026-53702?

CVE-2026-53702 is a medium-severity memory corruption vulnerability in Red Hat Enterprise Linux 10, published on 11 Jun 2026. An attacker can exploit it over the internet without logging in, and only if a user opens a file or follows a link.

### Official description

A stack buffer overflow flaw was found in the GStreamer H.265 codec parser library (gst-plugins-bad). When parsing a buffering period SEI message, the parser uses an incorrect loop bound derived from cpb_cnt_minus1[i] (the loop index) instead of the sub-layer 0 CPB count cpb_cnt_minus1[0] from the referenced Sequence Parameter Set. A crafted H.265 video file or stream can cause the parser to write beyond the bounds of stack-allocated CPB delay arrays, resulting in a crash or potential stack memory corruption.

Weakness: CWE-787 (Out-of-bounds Write)

## Which versions are affected by CVE-2026-53702?


## How do I fix CVE-2026-53702?

Apply the vendor's patch.

## Is CVE-2026-53702 being exploited?

There is no known exploitation of CVE-2026-53702 in the wild and no public exploit code.

## Fix prompt for AI coding agents

```text
Check this codebase for CVE-2026-53702 and fix it if it is affected.

What it is: CVE-2026-53702 is a medium-severity memory corruption vulnerability in Red Hat Enterprise Linux 10, published on 11 Jun 2026. An attacker can exploit it over the internet without logging in, and only if a user opens a file or follows a link.
Exploitation: There is no known exploitation of CVE-2026-53702 in the wild and no public exploit code.

Affected product: Red Hat Enterprise Linux 10. No package-level version data is available, so check the vendor advisory linked from the reference page.

Task:
1. Search the dependency manifests and lockfiles (for example package.json, package-lock.json, requirements.txt, poetry.lock, uv.lock, pom.xml, build.gradle, go.mod, Cargo.lock, Gemfile.lock) and any Dockerfiles for the affected packages, including transitive dependencies.
2. If an affected version is in use, upgrade it to the fixed version for its release line with the project's package manager, so the lockfile is regenerated. Prefer the smallest upgrade that fixes it.
3. If there is no fix, or the upgrade would break the build, do not guess: explain the risk and the safest workaround instead.
4. Run the tests and summarise what changed and why.
5. If nothing in the project is affected, say so and change nothing.

Reference: https://insights.sbomify.com/CVE-2026-53702/ (Markdown: https://insights.sbomify.com/CVE-2026-53702/index.md)
```

## Sources

- CVE record: https://www.cve.org/CVERecord?id=CVE-2026-53702
- NVD: https://nvd.nist.gov/vuln/detail/CVE-2026-53702
- OSV: https://osv.dev/vulnerability/CVE-2026-53702

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From sbomify Insights: https://insights.sbomify.com/CVE-2026-53702/
Summaries are generated and may contain mistakes; the official description above is the record.