# CVE-2026-22993: idpf: Fix RSS LUT NULL ptr issue after soft reset

> A local attacker can cause a kernel crash by triggering a NULL pointer dereference in the idpf driver during a soft reset sequence.

- **Severity:** Medium 5.5 (`CVSS:3.1/AV:L/AC:L/PR:L/UI:N/S:U/C:N/I:N/A:H`)
- **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:** 23 Jan 2026
- **Updated:** 11 May 2026
- **Also known as:** BELL-CVE-2026-22993, DEBIAN-CVE-2026-22993, GHSA-42mq-7943-cj3h, ROOT-OS-DEBIAN-13-CVE-2026-22993, ROOT-OS-UBUNTU-2404-CVE-2026-22993, UBUNTU-CVE-2026-22993

## What is CVE-2026-22993?

CVE-2026-22993 is a medium-severity vulnerability in Linux kernel, published on 23 Jan 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:

idpf: Fix RSS LUT NULL ptr issue after soft reset

During soft reset, the RSS LUT is freed and not restored unless the
interface is up. If an ethtool command that accesses the rss lut is
attempted immediately after reset, it will result in NULL ptr
dereference. Also, there is no need to reset the rss lut if the soft reset
does not involve queue count change.

After soft reset, set the RSS LUT to default values based on the updated
queue count only if the reset was a result of a queue count change and
the LUT was not configured by the user. In all other cases, don't touch
the LUT.

Steps to reproduce:

** Bring the interface down (if up)
ifconfig eth1 down

** update the queue count (eg., 27->20)
ethtool -L eth1 combined 20

** display the RSS LUT
ethtool -x eth1

[82375.558338] BUG: kernel NULL pointer dereference, address: 0000000000000000
[82375.558373] #PF: supervisor read access in kernel mode
[82375.558391] #PF: error_code(0x0000) - not-present page
[82375.558408] PGD 0 P4D 0
[82375.558421] Oops: Oops: 0000 [#1] SMP NOPTI
<snip>
[82375.558516] RIP: 0010:idpf_get_rxfh+0x108/0x150 [idpf]
[82375.558786] Call Trace:
[82375.558793]  <TASK>
[82375.558804]  rss_prepare.isra.0+0x187/0x2a0
[82375.558827]  rss_prepare_data+0x3a/0x50
[82375.558845]  ethnl_default_doit+0x13d/0x3e0
[82375.558863]  genl_family_rcv_msg_doit+0x11f/0x180
[82375.558886]  genl_rcv_msg+0x1ad/0x2b0
[82375.558902]  ? __pfx_ethnl_default_doit+0x10/0x10
[82375.558920]  ? __pfx_genl_rcv_msg+0x10/0x10
[82375.558937]  netlink_rcv_skb+0x58/0x100
[82375.558957]  genl_rcv+0x2c/0x50
[82375.558971]  netlink_unicast+0x289/0x3e0
[82375.558988]  netlink_sendmsg+0x215/0x440
[82375.559005]  __sys_sendto+0x234/0x240
[82375.559555]  __x64_sys_sendto+0x28/0x30
[82375.560068]  x64_sys_call+0x1909/0x1da0
[82375.560576]  do_syscall_64+0x7a/0xfa0
[82375.561076]  ? clear_bhb_loop+0x60/0xb0
[82375.561567]  entry_SYSCALL_64_after_hwframe+0x76/0x7e
<snip>

Weakness: CWE-476 (NULL Pointer Dereference)

## Which versions are affected by CVE-2026-22993?

It affects 1 product.


Products: Linux kernel.

## How do I fix CVE-2026-22993?

Apply the vendor's patch.

## Is CVE-2026-22993 being exploited?

There is no known exploitation of CVE-2026-22993 in the wild and no public exploit code.

## Other vulnerabilities in Linux kernel

- [CVE-2026-53266](https://insights.sbomify.com/CVE-2026-53266/): Linux Kernel Out-of-Bounds Write (high 8.8, exploited in the wild)
- [CVE-2013-6282](https://insights.sbomify.com/CVE-2013-6282/): Linux Kernel Improper Input Validation (high 8.8, exploited in the wild)
- [CVE-2022-0185](https://insights.sbomify.com/CVE-2022-0185/): Linux Kernel Heap-Based Buffer Overflow (high 8.4, exploited in the wild)
- [CVE-2013-2094](https://insights.sbomify.com/CVE-2013-2094/): Linux Kernel Privilege Escalation (high 8.4, exploited in the wild)
- [CVE-2026-53362](https://insights.sbomify.com/CVE-2026-53362/): Linux Kernel Unspecified (high 7.8, exploited in the wild)

## Fix prompt for AI coding agents

```text
Check this codebase for CVE-2026-22993 and fix it if it is affected.

What it is: CVE-2026-22993 is a medium-severity vulnerability in Linux kernel, published on 23 Jan 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-2026-22993 in the wild and no public exploit code.

Affected product: Linux kernel. 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-2026-22993/ (Markdown: https://insights.sbomify.com/CVE-2026-22993/index.md)
```

## Sources

- CVE record: https://www.cve.org/CVERecord?id=CVE-2026-22993
- NVD: https://nvd.nist.gov/vuln/detail/CVE-2026-22993
- OSV: https://osv.dev/vulnerability/CVE-2026-22993

---
From sbomify Insights: https://insights.sbomify.com/CVE-2026-22993/
Summaries are generated and may contain mistakes; the official description above is the record.
