# CVE-2024-53139: sctp: fix possible UAF in sctp_v6_available()

> A use-after-free vulnerability in the Linux kernel SCTP module allows attackers to potentially execute code or escalate privileges via improper RCU locking.

- **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 Dec 2024
- **Updated:** 5 Aug 2026
- **Also known as:** AZL-54165, BELL-CVE-2024-53139, DEBIAN-CVE-2024-53139, GHSA-p28q-ghm8-cw23, UBUNTU-CVE-2024-53139

## What is CVE-2024-53139?

CVE-2024-53139 is a high-severity use after free vulnerability in Linux kernel, published on 4 Dec 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:

sctp: fix possible UAF in sctp_v6_available()

A lockdep report [1] with CONFIG_PROVE_RCU_LIST=y hints
that sctp_v6_available() is calling dev_get_by_index_rcu()
and ipv6_chk_addr() without holding rcu.

[1]
 =============================
 WARNING: suspicious RCU usage
 6.12.0-rc5-virtme #1216 Tainted: G        W
 -----------------------------
 net/core/dev.c:876 RCU-list traversed in non-reader section!!

other info that might help us debug this:

rcu_scheduler_active = 2, debug_locks = 1
 1 lock held by sctp_hello/31495:
 #0: ffff9f1ebbdb7418 (sk_lock-AF_INET6){+.+.}-{0:0}, at: sctp_bind (./arch/x86/include/asm/jump_label.h:27 net/sctp/socket.c:315) sctp

stack backtrace:
 CPU: 7 UID: 0 PID: 31495 Comm: sctp_hello Tainted: G        W          6.12.0-rc5-virtme #1216
 Tainted: [W]=WARN
 Hardware name: QEMU Standard PC (i440FX + PIIX, 1996), BIOS 1.16.3-debian-1.16.3-2 04/01/2014
 Call Trace:
  <TASK>
 dump_stack_lvl (lib/dump_stack.c:123)
 lockdep_rcu_suspicious (kernel/locking/lockdep.c:6822)
 dev_get_by_index_rcu (net/core/dev.c:876 (discriminator 7))
 sctp_v6_available (net/sctp/ipv6.c:701) sctp
 sctp_do_bind (net/sctp/socket.c:400 (discriminator 1)) sctp
 sctp_bind (net/sctp/socket.c:320) sctp
 inet6_bind_sk (net/ipv6/af_inet6.c:465)
 ? security_socket_bind (security/security.c:4581 (discriminator 1))
 __sys_bind (net/socket.c:1848 net/socket.c:1869)
 ? do_user_addr_fault (./include/linux/rcupdate.h:347 ./include/linux/rcupdate.h:880 ./include/linux/mm.h:729 arch/x86/mm/fault.c:1340)
 ? do_user_addr_fault (./arch/x86/include/asm/preempt.h:84 (discriminator 13) ./include/linux/rcupdate.h:98 (discriminator 13) ./include/linux/rcupdate.h:882 (discriminator 13) ./include/linux/mm.h:729 (discriminator 13) arch/x86/mm/fault.c:1340 (discriminator 13))
 __x64_sys_bind (net/socket.c:1877 (discriminator 1) net/socket.c:1875 (discriminator 1) net/socket.c:1875 (discriminator 1))
 do_syscall_64 (arch/x86/entry/common.c:52 (discriminator 1) arch/x86/entry/common.c:83 (discriminator 1))
 entry_SYSCALL_64_after_hwframe (arch/x86/entry/entry_64.S:130)
 RIP: 0033:0x7f59b934a1e7
 Code: 44 00 00 48 8b 15 39 8c 0c 00 f7 d8 64 89 02 b8 ff ff ff ff eb bd 66 2e 0f 1f 84 00 00 00 00 00 0f 1f 00 b8 31 00 00 00 0f 05 <48> 3d 01 f0 ff ff 73 01 c3 48 8b 0d 09 8c 0c 00 f7 d8 64 89 01 48
All code
========
   0:	44 00 00             	add    %r8b,(%rax)
   3:	48 8b 15 39 8c 0c 00 	mov    0xc8c39(%rip),%rdx        # 0xc8c43
   a:	f7 d8                	neg    %eax
   c:	64 89 02             	mov    %eax,%fs:(%rdx)
   f:	b8 ff ff ff ff       	mov    $0xffffffff,%eax
  14:	eb bd                	jmp    0xffffffffffffffd3
  16:	66 2e 0f 1f 84 00 00 	cs nopw 0x0(%rax,%rax,1)
  1d:	00 00 00
  20:	0f 1f 00             	nopl   (%rax)
  23:	b8 31 00 00 00       	mov    $0x31,%eax
  28:	0f 05                	syscall
  2a:*	48 3d 01 f0 ff ff    	cmp    $0xfffffffffffff001,%rax		<-- trapping instruction
  30:	73 01                	jae    0x33
  32:	c3                   	ret
  33:	48 8b 0d 09 8c 0c 00 	mov    0xc8c09(%rip),%rcx        # 0xc8c43
  3a:	f7 d8                	neg    %eax
  3c:	64 89 01             	mov    %eax,%fs:(%rcx)
  3f:	48                   	rex.W

Code starting with the faulting instruction
===========================================
   0:	48 3d 01 f0 ff ff    	cmp    $0xfffffffffffff001,%rax
   6:	73 01                	jae    0x9
   8:	c3                   	ret
   9:	48 8b 0d 09 8c 0c 00 	mov    0xc8c09(%rip),%rcx        # 0xc8c19
  10:	f7 d8                	neg    %eax
  12:	64 89 01             	mov    %eax,%fs:(%rcx)
  15:	48                   	rex.W
 RSP: 002b:00007ffe2d0ad398 EFLAGS: 00000202 ORIG_RAX: 0000000000000031
 RAX: ffffffffffffffda RBX: 00007ffe2d0ad3d0 RCX: 00007f59b934a1e7
 RDX: 000000000000001c RSI: 00007ffe2d0ad3d0 RDI: 0000000000000005
 RBP: 0000000000000005 R08: 1999999999999999 R09: 0000000000000000
 R10: 00007f59b9253298 R11: 000000000000
---truncated---

Weakness: CWE-416 (Use After Free)

## Which versions are affected by CVE-2024-53139?

It affects 1 product.


Products: Linux kernel.

## How do I fix CVE-2024-53139?

Apply the vendor's patch.

## Is CVE-2024-53139 being exploited?

There is no known exploitation of CVE-2024-53139 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-2024-53139 and fix it if it is affected.

What it is: CVE-2024-53139 is a high-severity use after free vulnerability in Linux kernel, published on 4 Dec 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-2024-53139 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-2024-53139/ (Markdown: https://insights.sbomify.com/CVE-2024-53139/index.md)
```

## Sources

- CVE record: https://www.cve.org/CVERecord?id=CVE-2024-53139
- NVD: https://nvd.nist.gov/vuln/detail/CVE-2024-53139
- OSV: https://osv.dev/vulnerability/CVE-2024-53139

---
From sbomify Insights: https://insights.sbomify.com/CVE-2024-53139/
Summaries are generated and may contain mistakes; the official description above is the record.