# CVE-2026-26453: Null dereference in n/a

> A null pointer dereference in the ccoap library allows attackers to cause a denial of service via crafted COAP messages.

- **Severity:** High 7.5 (`CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/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:** No
- **Published:** 27 Aug 2026
- **Updated:** 1 Sep 2026
- **Also known as:** GHSA-cmf6-2rf8-75m6

## What is CVE-2026-26453?

CVE-2026-26453 is a high-severity vulnerability in n/a, published on 27 Aug 2026. An attacker can exploit it over the internet without logging in, with no action from the victim.

### Official description

ccoap 77f55c4b466e99327c24ace8a2913d3ba7e2ccd5 contains a null pointer dereference vulnerability in the coap_server_handle_session() function when processing COAP messages containing URI_PATH options with NULL data pointers. When the server searches for a URI_PATH option matching the string "separate", it directly calls strncmp() on option_list[i].data without checking if the pointer is NULL. This causes a segmentation fault when the option's data field is NULL.

Weakness: CWE-476 (NULL Pointer Dereference)

## Which versions are affected by CVE-2026-26453?


## How do I fix CVE-2026-26453?

No fix has been published for CVE-2026-26453 yet. Limit exposure of the affected software until one is available.

## Is CVE-2026-26453 being exploited?

It is not confirmed as exploited in the wild, but public exploit code for CVE-2026-26453 exists.

## Fix prompt for AI coding agents

```text
Check this codebase for CVE-2026-26453 and fix it if it is affected.

What it is: CVE-2026-26453 is a high-severity vulnerability in n/a, published on 27 Aug 2026. An attacker can exploit it over the internet without logging in, with no action from the victim.
Exploitation: It is not confirmed as exploited in the wild, but public exploit code for CVE-2026-26453 exists.

Affected product: n/a. 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-2026-26453/ (Markdown: https://insights.sbomify.com/CVE-2026-26453/index.md)
```

## Sources

- CVE record: https://www.cve.org/CVERecord?id=CVE-2026-26453
- NVD: https://nvd.nist.gov/vuln/detail/CVE-2026-26453
- OSV: https://osv.dev/vulnerability/CVE-2026-26453

---
From sbomify Insights: https://insights.sbomify.com/CVE-2026-26453/
Summaries are generated and may contain mistakes; the official description above is the record.