# CVE-2026-97615: net: bridge: use option bits for CFM/MRP frame handlers

> A memory corruption vulnerability in the Linux kernel bridge module allows attackers to corrupt list states, potentially causing denial of service or code execution.

- **Severity:** Not scored
- **Exploited in the wild:** Not known
- **Login needed:** Not needed
- **Attackable:** Local or same network only
- **Victim action needed:** Not needed
- **Fix available:** Yes
- **Published:** 25 Sep 2026
- **Updated:** 21 Oct 2026
- **Also known as:** AZL-104274, BELL-CVE-2026-97615, DEBIAN-CVE-2026-97615, GHSA-jx7q-xjrp-x794, UBUNTU-CVE-2026-97615

## What is CVE-2026-97615?

CVE-2026-97615 is a memory corruption vulnerability in Linux, published on 25 Sep 2026. It can only be exploited from the same machine or local network, with no action from the victim.

### Official description

In the Linux kernel, the following vulnerability has been resolved:

net: bridge: use option bits for CFM/MRP frame handlers

CFM and MRP register a global br_frame_type whose hlist_node is linked
into the per-bridge frame_type_list when the first MEP/MRP instance is
created. Enabling the protocol on multiple bridges therefore inserts the
same node into multiple lists. Unregistering it on one bridge then
corrupts list state belonging to another.

These handlers can only be installed once per bridge, and they are
uncommon. Track their per-bridge enable state with net_bridge option
bits, which already live on the Rx hot cache line, and dispatch the
matching handler directly from the receive path. Check both bits
together first as an unlikely case.

Remove the generic frame_type_list and br_frame_type helpers, which
have had no other users since CFM and MRP were added. That shrinks
struct net_bridge by 8 bytes and drops the list walk from the fast
path. When neither protocol is compiled in, BR_CFM_MRP_OPTS is 0 and
the compiler prunes the branch.

## Which versions are affected by CVE-2026-97615?


## How do I fix CVE-2026-97615?

Apply the vendor's patch.

## Is CVE-2026-97615 being exploited?

There is no known exploitation of CVE-2026-97615 in the wild and no public exploit code.

## Fix prompt for AI coding agents

```text
Check this codebase for CVE-2026-97615 and fix it if it is affected.

What it is: CVE-2026-97615 is a memory corruption vulnerability in Linux, published on 25 Sep 2026. It can only be exploited from the same machine or local network, with no action from the victim.
Exploitation: There is no known exploitation of CVE-2026-97615 in the wild and no public exploit code.

Affected product: Linux. No package-level version data is available, so check the vendor advisory linked from the reference page.

Task:
1. Search the dependency manifests and lockfiles (for example package.json, package-lock.json, requirements.txt, poetry.lock, uv.lock, pom.xml, build.gradle, go.mod, Cargo.lock, Gemfile.lock) and any Dockerfiles for the affected packages, including transitive dependencies.
2. If an affected version is in use, upgrade it to the fixed version for its release line with the project's package manager, so the lockfile is regenerated. Prefer the smallest upgrade that fixes it.
3. If there is no fix, or the upgrade would break the build, do not guess: explain the risk and the safest workaround instead.
4. Run the tests and summarise what changed and why.
5. If nothing in the project is affected, say so and change nothing.

Reference: https://insights.sbomify.com/CVE-2026-97615/ (Markdown: https://insights.sbomify.com/CVE-2026-97615/index.md)
```

## Sources

- CVE record: https://www.cve.org/CVERecord?id=CVE-2026-97615
- NVD: https://nvd.nist.gov/vuln/detail/CVE-2026-97615
- OSV: https://osv.dev/vulnerability/CVE-2026-97615

---
From sbomify Insights: https://insights.sbomify.com/CVE-2026-97615/
Summaries are generated and may contain mistakes; the official description above is the record.