# CVE-2026-90299: bpf: Fix sleepable check for tracing/lsm prog

> A local attacker can trigger a kernel BUG and denial of service by attaching a sleepable BPF program to a specific target when error injection is disabled.

- **Severity:** Not scored
- **Exploited in the wild:** Not known
- **Login needed:** Any signed-in user
- **Attackable:** Local or same network only
- **Victim action needed:** Not needed
- **Fix available:** Yes
- **Published:** 17 Sep 2026
- **Updated:** 19 Oct 2026
- **Also known as:** DEBIAN-CVE-2026-90299, GHSA-6wg8-p2j3-rxg8, UBUNTU-CVE-2026-90299

## What is CVE-2026-90299?

CVE-2026-90299 is a denial of service vulnerability in Linux, published on 17 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:

bpf: Fix sleepable check for tracing/lsm prog

When CONFIG_FUNCTION_ERROR_INJECTION is disabled, a sleepable tracing prog
is allowed to attach to '__x64_'-alike prefix symbols.

It is because the verifier does not verify whether the symbol is a kernel
function or a bpf prog. That said, a sleepable tracing prog is allowed to
attach to a bpf prog target whose name has '__x64_'-alike prefix.

For example, a sleepable fentry prog attaches to a '__x64_sys_nop' XDP
prog, and copies buffer from a user pointer with bpf_copy_from_user()
helper. After attaching the XDP prog to lo interface, the kernel BUG
could be triggered by 'ping -c 1 -W 1 127.0.0.1':

[    3.460756] BUG: sleeping function called from invalid context at kernel/bpf/trampoline.c:1324

Fix it by disallowing sleepable prog always when its target
btf is not a kernel's btf.

## Which versions are affected by CVE-2026-90299?


## How do I fix CVE-2026-90299?

Apply the vendor's patch.

## Is CVE-2026-90299 being exploited?

There is no known exploitation of CVE-2026-90299 in the wild and no public exploit code.

## Fix prompt for AI coding agents

```text
Check this codebase for CVE-2026-90299 and fix it if it is affected.

What it is: CVE-2026-90299 is a denial of service vulnerability in Linux, published on 17 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-2026-90299 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-2026-90299/ (Markdown: https://insights.sbomify.com/CVE-2026-90299/index.md)
```

## Sources

- CVE record: https://www.cve.org/CVERecord?id=CVE-2026-90299
- NVD: https://nvd.nist.gov/vuln/detail/CVE-2026-90299
- OSV: https://osv.dev/vulnerability/CVE-2026-90299

---
From sbomify Insights: https://insights.sbomify.com/CVE-2026-90299/
Summaries are generated and may contain mistakes; the official description above is the record.