# CVE-2026-68320: sctp: fix auth_chunk_list capacity check in sctp_auth_ep_add_chunkid

> A buffer overflow in the Linux kernel SCTP implementation allows attackers to corrupt memory, potentially leading to code execution or privilege escalation.

- **Severity:** High 7.3 (`CVSS:3.1/AV:L/AC:L/PR:L/UI:N/S:U/C:L/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:** 10 Aug 2026
- **Updated:** 19 Oct 2026
- **Also known as:** BELL-CVE-2026-68320, DEBIAN-CVE-2026-68320, GHSA-f7gm-j66v-p95w, UBUNTU-CVE-2026-68320

## What is CVE-2026-68320?

CVE-2026-68320 is a high-severity memory corruption vulnerability in Linux, published on 10 Aug 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:

sctp: fix auth_chunk_list capacity check in sctp_auth_ep_add_chunkid

sctp_auth_ep_add_chunkid() uses SCTP_NUM_CHUNK_TYPES (20) as the
capacity limit for ep->auth_chunk_list, allowing it to hold up to
20 chunk entries (param_hdr.length up to 24). However, the copy
destination asoc->c.auth_chunks in struct sctp_cookie is only
SCTP_AUTH_MAX_CHUNKS (16) entries (20 bytes). When more than 16
chunks are added, sctp_association_init() memcpy overflows the
destination by up to 4 bytes.

Fix by using SCTP_AUTH_MAX_CHUNKS as the capacity limit, matching
the destination capacity.

Weakness: CWE-787 (Out-of-bounds Write)

## Which versions are affected by CVE-2026-68320?


## How do I fix CVE-2026-68320?

Apply the vendor's patch.

## Is CVE-2026-68320 being exploited?

There is no known exploitation of CVE-2026-68320 in the wild and no public exploit code.

## Fix prompt for AI coding agents

```text
Check this codebase for CVE-2026-68320 and fix it if it is affected.

What it is: CVE-2026-68320 is a high-severity memory corruption vulnerability in Linux, published on 10 Aug 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-2026-68320 in the wild and no public exploit code.

Affected product: Linux. 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-2026-68320/ (Markdown: https://insights.sbomify.com/CVE-2026-68320/index.md)
```

## Sources

- CVE record: https://www.cve.org/CVERecord?id=CVE-2026-68320
- NVD: https://nvd.nist.gov/vuln/detail/CVE-2026-68320
- OSV: https://osv.dev/vulnerability/CVE-2026-68320

---
From sbomify Insights: https://insights.sbomify.com/CVE-2026-68320/
Summaries are generated and may contain mistakes; the official description above is the record.