# CVE-2024-26793: gtp: fix use-after-free and null-ptr-deref in gtp_newlink()

> A use-after-free and null pointer dereference in the Linux kernel GTP module allows local attackers to cause a system crash.

- **Severity:** High 7.8 (`CVSS:3.1/AV:L/AC:L/PR:L/UI:N/S:U/C:H/I:H/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 Apr 2024
- **Updated:** 5 Aug 2026
- **Also known as:** BELL-CVE-2024-26793, DEBIAN-CVE-2024-26793, GHSA-3v83-crv9-cf9p, UBUNTU-CVE-2024-26793

## What is CVE-2024-26793?

CVE-2024-26793 is a high-severity use after free vulnerability in Linux kernel, published on 4 Apr 2024. 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:

gtp: fix use-after-free and null-ptr-deref in gtp_newlink()

The gtp_link_ops operations structure for the subsystem must be
registered after registering the gtp_net_ops pernet operations structure.

Syzkaller hit 'general protection fault in gtp_genl_dump_pdp' bug:

[ 1010.702740] gtp: GTP module unloaded
[ 1010.715877] general protection fault, probably for non-canonical address 0xdffffc0000000001: 0000 [#1] SMP KASAN NOPTI
[ 1010.715888] KASAN: null-ptr-deref in range [0x0000000000000008-0x000000000000000f]
[ 1010.715895] CPU: 1 PID: 128616 Comm: a.out Not tainted 6.8.0-rc6-std-def-alt1 #1
[ 1010.715899] Hardware name: QEMU Standard PC (Q35 + ICH9, 2009), BIOS 1.16.0-alt1 04/01/2014
[ 1010.715908] RIP: 0010:gtp_newlink+0x4d7/0x9c0 [gtp]
[ 1010.715915] Code: 80 3c 02 00 0f 85 41 04 00 00 48 8b bb d8 05 00 00 e8 ed f6 ff ff 48 89 c2 48 89 c5 48 b8 00 00 00 00 00 fc ff df 48 c1 ea 03 <80> 3c 02 00 0f 85 4f 04 00 00 4c 89 e2 4c 8b 6d 00 48 b8 00 00 00
[ 1010.715920] RSP: 0018:ffff888020fbf180 EFLAGS: 00010203
[ 1010.715929] RAX: dffffc0000000000 RBX: ffff88800399c000 RCX: 0000000000000000
[ 1010.715933] RDX: 0000000000000001 RSI: ffffffff84805280 RDI: 0000000000000282
[ 1010.715938] RBP: 000000000000000d R08: 0000000000000001 R09: 0000000000000000
[ 1010.715942] R10: 0000000000000001 R11: 0000000000000001 R12: ffff88800399cc80
[ 1010.715947] R13: 0000000000000000 R14: 0000000000000000 R15: 0000000000000400
[ 1010.715953] FS:  00007fd1509ab5c0(0000) GS:ffff88805b300000(0000) knlGS:0000000000000000
[ 1010.715958] CS:  0010 DS: 0000 ES: 0000 CR0: 0000000080050033
[ 1010.715962] CR2: 0000000000000000 CR3: 000000001c07a000 CR4: 0000000000750ee0
[ 1010.715968] PKRU: 55555554
[ 1010.715972] Call Trace:
[ 1010.715985]  ? __die_body.cold+0x1a/0x1f
[ 1010.715995]  ? die_addr+0x43/0x70
[ 1010.716002]  ? exc_general_protection+0x199/0x2f0
[ 1010.716016]  ? asm_exc_general_protection+0x1e/0x30
[ 1010.716026]  ? gtp_newlink+0x4d7/0x9c0 [gtp]
[ 1010.716034]  ? gtp_net_exit+0x150/0x150 [gtp]
[ 1010.716042]  __rtnl_newlink+0x1063/0x1700
[ 1010.716051]  ? rtnl_setlink+0x3c0/0x3c0
[ 1010.716063]  ? is_bpf_text_address+0xc0/0x1f0
[ 1010.716070]  ? kernel_text_address.part.0+0xbb/0xd0
[ 1010.716076]  ? __kernel_text_address+0x56/0xa0
[ 1010.716084]  ? unwind_get_return_address+0x5a/0xa0
[ 1010.716091]  ? create_prof_cpu_mask+0x30/0x30
[ 1010.716098]  ? arch_stack_walk+0x9e/0xf0
[ 1010.716106]  ? stack_trace_save+0x91/0xd0
[ 1010.716113]  ? stack_trace_consume_entry+0x170/0x170
[ 1010.716121]  ? __lock_acquire+0x15c5/0x5380
[ 1010.716139]  ? mark_held_locks+0x9e/0xe0
[ 1010.716148]  ? kmem_cache_alloc_trace+0x35f/0x3c0
[ 1010.716155]  ? __rtnl_newlink+0x1700/0x1700
[ 1010.716160]  rtnl_newlink+0x69/0xa0
[ 1010.716166]  rtnetlink_rcv_msg+0x43b/0xc50
[ 1010.716172]  ? rtnl_fdb_dump+0x9f0/0x9f0
[ 1010.716179]  ? lock_acquire+0x1fe/0x560
[ 1010.716188]  ? netlink_deliver_tap+0x12f/0xd50
[ 1010.716196]  netlink_rcv_skb+0x14d/0x440
[ 1010.716202]  ? rtnl_fdb_dump+0x9f0/0x9f0
[ 1010.716208]  ? netlink_ack+0xab0/0xab0
[ 1010.716213]  ? netlink_deliver_tap+0x202/0xd50
[ 1010.716220]  ? netlink_deliver_tap+0x218/0xd50
[ 1010.716226]  ? __virt_addr_valid+0x30b/0x590
[ 1010.716233]  netlink_unicast+0x54b/0x800
[ 1010.716240]  ? netlink_attachskb+0x870/0x870
[ 1010.716248]  ? __check_object_size+0x2de/0x3b0
[ 1010.716254]  netlink_sendmsg+0x938/0xe40
[ 1010.716261]  ? netlink_unicast+0x800/0x800
[ 1010.716269]  ? __import_iovec+0x292/0x510
[ 1010.716276]  ? netlink_unicast+0x800/0x800
[ 1010.716284]  __sock_sendmsg+0x159/0x190
[ 1010.716290]  ____sys_sendmsg+0x712/0x880
[ 1010.716297]  ? sock_write_iter+0x3d0/0x3d0
[ 1010.716304]  ? __ia32_sys_recvmmsg+0x270/0x270
[ 1010.716309]  ? lock_acquire+0x1fe/0x560
[ 1010.716315]  ? drain_array_locked+0x90/0x90
[ 1010.716324]  ___sys_sendmsg+0xf8/0x170
[ 1010.716331]  ? sendmsg_copy_msghdr+0x170/0x170
[ 1010.716337]  ? lockdep_init_map
---truncated---

Weakness: CWE-476 (NULL Pointer Dereference), CWE-416 (Use After Free)

## Which versions are affected by CVE-2024-26793?

It affects 1 product.


Products: Linux kernel.

## How do I fix CVE-2024-26793?

Apply the vendor's patch.

## Is CVE-2024-26793 being exploited?

There is no known exploitation of CVE-2024-26793 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-2024-26793 and fix it if it is affected.

What it is: CVE-2024-26793 is a high-severity use after free vulnerability in Linux kernel, published on 4 Apr 2024. 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-2024-26793 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-2024-26793/ (Markdown: https://insights.sbomify.com/CVE-2024-26793/index.md)
```

## Sources

- CVE record: https://www.cve.org/CVERecord?id=CVE-2024-26793
- NVD: https://nvd.nist.gov/vuln/detail/CVE-2024-26793
- OSV: https://osv.dev/vulnerability/CVE-2024-26793

---
From sbomify Insights: https://insights.sbomify.com/CVE-2024-26793/
Summaries are generated and may contain mistakes; the official description above is the record.
