# CVE-2026-89847: scsi: qla2xxx: Avoid double completion in async IOCB timeout

> A use-after-free in the qla2xxx SCSI driver allows attackers to execute arbitrary code or escalate privileges via a race condition in async IOCB timeout handling.

- **Severity:** Critical 9.8 (`CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:H/A:H`)
- **Exploited in the wild:** Not known
- **Login needed:** Not needed
- **Attackable:** Over the internet
- **Victim action needed:** Not needed
- **Fix available:** Yes
- **Published:** 16 Sep 2026
- **Updated:** 19 Oct 2026
- **Also known as:** AZL-101352, BELL-CVE-2026-89847, DEBIAN-CVE-2026-89847, GHSA-6f8q-4cvp-fr9q, UBUNTU-CVE-2026-89847

## What is CVE-2026-89847?

CVE-2026-89847 is a critical use after free vulnerability in Linux, published on 16 Sep 2026. An attacker can exploit it over the internet without logging in, with no action from the victim.

### Official description

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

scsi: qla2xxx: Avoid double completion in async IOCB timeout

qla2x00_async_iocb_timeout() tries to abort a timed-out async IOCB. When
qla24xx_async_abort_cmd() fails, both the SRB_LOGIN_CMD path and the
SRB_CTRL_VP/default path scan outstanding_cmds[] for the SRB and then
call sp->done(sp, QLA_FUNCTION_TIMEOUT) unconditionally, without checking
whether the SRB was actually found and removed.

If the response ISR completes the same handle first, it removes the SRB
under qp_lock_ptr and runs sp->done() -> complete(sp->comp). The
submitter qla24xx_control_vp() wakes from wait_for_completion(), clears
sp->comp, drops its reference and returns, reclaiming the on-stack
completion. The timer reference keeps the SRB alive across the timeout
handler, but not the submitter's stack. The timeout then issues a second
sp->done() -> qla_ctrlvp_sp_done(), which evaluates "if (sp->comp)
complete(sp->comp)"; with the pointer loaded before the submitter's NULL
store, complete() writes into the freed stack frame, a use-after-free.

Track whether this path removed the SRB from outstanding_cmds and only
call sp->done() when it did, so the command is completed exactly once by
whichever path owns it. This mirrors the sp_found guard already used in
qla24xx_abort_iocb_timeout().

## Which versions are affected by CVE-2026-89847?


## How do I fix CVE-2026-89847?

Apply the vendor's patch.

## Is CVE-2026-89847 being exploited?

There is no known exploitation of CVE-2026-89847 in the wild and no public exploit code.

## Fix prompt for AI coding agents

```text
Check this codebase for CVE-2026-89847 and fix it if it is affected.

What it is: CVE-2026-89847 is a critical use after free vulnerability in Linux, published on 16 Sep 2026. An attacker can exploit it over the internet without logging in, with no action from the victim.
Exploitation: There is no known exploitation of CVE-2026-89847 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-2026-89847/ (Markdown: https://insights.sbomify.com/CVE-2026-89847/index.md)
```

## Sources

- CVE record: https://www.cve.org/CVERecord?id=CVE-2026-89847
- NVD: https://nvd.nist.gov/vuln/detail/CVE-2026-89847
- OSV: https://osv.dev/vulnerability/CVE-2026-89847

---
From sbomify Insights: https://insights.sbomify.com/CVE-2026-89847/
Summaries are generated and may contain mistakes; the official description above is the record.