# CVE-2026-23064: net/sched: act_ife: avoid possible NULL deref

> A NULL pointer dereference in the Linux kernel's IFE action allows local attackers to cause a system crash via crafted network packets.

- **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:** 4 Feb 2026
- **Updated:** 11 May 2026
- **Also known as:** BELL-CVE-2026-23064, DEBIAN-CVE-2026-23064, GHSA-949x-gvhg-pggc, ROOT-OS-UBUNTU-2204-CVE-2026-23064, ROOT-OS-UBUNTU-2404-CVE-2026-23064, UBUNTU-CVE-2026-23064

## What is CVE-2026-23064?

CVE-2026-23064 is a medium-severity vulnerability in Linux kernel, published on 4 Feb 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/sched: act_ife: avoid possible NULL deref

tcf_ife_encode() must make sure ife_encode() does not return NULL.

syzbot reported:

Oops: general protection fault, probably for non-canonical address 0xdffffc0000000000: 0000 [#1] SMP KASAN NOPTI
KASAN: null-ptr-deref in range [0x0000000000000000-0x0000000000000007]
 RIP: 0010:ife_tlv_meta_encode+0x41/0xa0 net/ife/ife.c:166
CPU: 3 UID: 0 PID: 8990 Comm: syz.0.696 Not tainted syzkaller #0 PREEMPT(full)
Call Trace:
 <TASK>
  ife_encode_meta_u32+0x153/0x180 net/sched/act_ife.c:101
  tcf_ife_encode net/sched/act_ife.c:841 [inline]
  tcf_ife_act+0x1022/0x1de0 net/sched/act_ife.c:877
  tc_act include/net/tc_wrapper.h:130 [inline]
  tcf_action_exec+0x1c0/0xa20 net/sched/act_api.c:1152
  tcf_exts_exec include/net/pkt_cls.h:349 [inline]
  mall_classify+0x1a0/0x2a0 net/sched/cls_matchall.c:42
  tc_classify include/net/tc_wrapper.h:197 [inline]
  __tcf_classify net/sched/cls_api.c:1764 [inline]
  tcf_classify+0x7f2/0x1380 net/sched/cls_api.c:1860
  multiq_classify net/sched/sch_multiq.c:39 [inline]
  multiq_enqueue+0xe0/0x510 net/sched/sch_multiq.c:66
  dev_qdisc_enqueue+0x45/0x250 net/core/dev.c:4147
  __dev_xmit_skb net/core/dev.c:4262 [inline]
  __dev_queue_xmit+0x2998/0x46c0 net/core/dev.c:4798

Weakness: CWE-476 (NULL Pointer Dereference)

## Which versions are affected by CVE-2026-23064?

It affects 1 product.


Products: Linux kernel.

## How do I fix CVE-2026-23064?

Apply the vendor's patch.

## Is CVE-2026-23064 being exploited?

There is no known exploitation of CVE-2026-23064 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-2026-23064 and fix it if it is affected.

What it is: CVE-2026-23064 is a medium-severity vulnerability in Linux kernel, published on 4 Feb 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-2026-23064 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-2026-23064/ (Markdown: https://insights.sbomify.com/CVE-2026-23064/index.md)
```

## Sources

- CVE record: https://www.cve.org/CVERecord?id=CVE-2026-23064
- NVD: https://nvd.nist.gov/vuln/detail/CVE-2026-23064
- OSV: https://osv.dev/vulnerability/CVE-2026-23064

---
From sbomify Insights: https://insights.sbomify.com/CVE-2026-23064/
Summaries are generated and may contain mistakes; the official description above is the record.