# CVE-2026-53224: sctp: validate embedded INIT chunk and address list lengths in cookie

> A remote attacker can trigger out-of-bounds reads in the Linux kernel SCTP implementation by sending malformed COOKIE_ECHO chunks, potentially causing crashes or leaking memory.

- **Severity:** Critical 9.1 (`CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:N/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:** 25 Jun 2026
- **Updated:** 21 Oct 2026
- **Also known as:** AZL-90522, BELL-CVE-2026-53224, DEBIAN-CVE-2026-53224, GHSA-h634-6f45-j5wj, ROOT-OS-DEBIAN-11-CVE-2026-53224, ROOT-OS-DEBIAN-12-CVE-2026-53224, ROOT-OS-DEBIAN-13-CVE-2026-53224, ROOT-OS-UBUNTU-2204-CVE-2026-53224, ROOT-OS-UBUNTU-2404-CVE-2026-53224, UBUNTU-CVE-2026-53224

## What is CVE-2026-53224?

CVE-2026-53224 is a critical memory corruption vulnerability in Linux kernel, published on 25 Jun 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:

sctp: validate embedded INIT chunk and address list lengths in cookie

sctp_unpack_cookie() only checked that the embedded INIT chunk length
did not exceed the remaining cookie payload, but did not ensure that the
INIT chunk is large enough to contain a complete INIT header.

A malformed COOKIE_ECHO can therefore carry a truncated INIT chunk whose
length field is smaller than sizeof(struct sctp_init_chunk).  Later,
sctp_process_init() accesses INIT parameters unconditionally, which may
lead to out-of-bounds reads.

In addition, raw_addr_list_len is not fully validated against the
remaining cookie payload. When cookie authentication is disabled, an
attacker can supply an oversized raw_addr_list_len and cause
sctp_raw_to_bind_addrs() to read beyond the end of the cookie. The
address parser also lacks sufficient bounds checks for parameter headers
and lengths, allowing malformed address parameters to trigger
out-of-bounds reads.

Fix this by:

- requiring the embedded INIT chunk length to be at least sizeof(struct
  sctp_init_chunk);
- validating that the INIT chunk and raw address list together fit
  within the cookie payload;
- verifying sufficient data exists for each address parameter header and
  payload before parsing it.

Note that sctp_verify_init() must be called after sctp_unpack_cookie()
and before sctp_process_init() when cookie authentication is disabled.
This will be addressed in a separate patch.

Weakness: CWE-125 (Out-of-bounds Read)

## Which versions are affected by CVE-2026-53224?

It affects 1 product.


Products: Linux kernel.

## How do I fix CVE-2026-53224?

Apply the vendor's patch.

## Is CVE-2026-53224 being exploited?

There is no known exploitation of CVE-2026-53224 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-2026-53224 and fix it if it is affected.

What it is: CVE-2026-53224 is a critical memory corruption vulnerability in Linux kernel, published on 25 Jun 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-2026-53224 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-2026-53224/ (Markdown: https://insights.sbomify.com/CVE-2026-53224/index.md)
```

## Sources

- CVE record: https://www.cve.org/CVERecord?id=CVE-2026-53224
- NVD: https://nvd.nist.gov/vuln/detail/CVE-2026-53224
- OSV: https://osv.dev/vulnerability/CVE-2026-53224

---
From sbomify Insights: https://insights.sbomify.com/CVE-2026-53224/
Summaries are generated and may contain mistakes; the official description above is the record.