# CVE-2026-55742: Cotonti CSRF in admin.rights.php allows privilege escalation

> Attackers can force admins to change group access rights via CSRF, leading to privilege escalation in Cotonti CMS.

- **Severity:** Critical 9.4 (`CVSS:4.0/AV:N/AC:L/AT:N/PR:N/UI:P/VC:H/VI:H/VA:H/SC:H/SI:H/SA:H`)
- **Exploited in the wild:** Not known
- **Login needed:** Not needed
- **Attackable:** Over the internet
- **Victim action needed:** A user has to click or open something
- **Fix available:** No
- **Published:** 18 Jun 2026
- **Updated:** 10 Aug 2026
- **Also known as:** GHSA-7g3p-35vc-mgjr

## What is CVE-2026-55742?

CVE-2026-55742 is a critical vulnerability in Cotonti, published on 18 Jun 2026. An attacker can exploit it over the internet without logging in, and only if a user opens a file or follows a link.

### Official description

Cotonti 1.0.0 (master branch, commit f43f1fc3) is vulnerable to Cross-Site Request Forgery in the administration rights handler. In system/admin/admin.rights.php, the rights update action ('a=update') modifies group access rights (including via cot_auth_add_group) without calling cot_check_xg to validate the anti-CSRF token.

Weakness: CWE-352 (Cross-Site Request Forgery)

## Which versions are affected by CVE-2026-55742?

2 open source packages ship an affected version, including cotonti/cotonti.


| Package | Ecosystem | Affected | Fixed in |
| --- | --- | --- | --- |
| `cotonti/cotonti` | Packagist | All versions to 1.0.0 | None |
| `cotonti/cotonti` | Packagist | All versions to 1.0.0 | None |

## How do I fix CVE-2026-55742?

No fix has been published for CVE-2026-55742 yet. Limit exposure of the affected software until one is available.

## Is CVE-2026-55742 being exploited?

There is no known exploitation of CVE-2026-55742 in the wild and no public exploit code.

## Fix prompt for AI coding agents

```text
Check this codebase for CVE-2026-55742 and fix it if it is affected.

What it is: CVE-2026-55742 is a critical vulnerability in Cotonti, published on 18 Jun 2026. An attacker can exploit it over the internet without logging in, and only if a user opens a file or follows a link.
Exploitation: There is no known exploitation of CVE-2026-55742 in the wild and no public exploit code.

Affected packages and fixed versions:
- cotonti/cotonti (Packagist): affected all versions up to 1.0.0; no fix listed
- cotonti/cotonti (Packagist): affected all versions up to 1.0.0; no fix listed

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-2026-55742/ (Markdown: https://insights.sbomify.com/CVE-2026-55742/index.md)
```

## Sources

- CVE record: https://www.cve.org/CVERecord?id=CVE-2026-55742
- NVD: https://nvd.nist.gov/vuln/detail/CVE-2026-55742
- OSV: https://osv.dev/vulnerability/CVE-2026-55742

---
From sbomify Insights: https://insights.sbomify.com/CVE-2026-55742/
Summaries are generated and may contain mistakes; the official description above is the record.