CVE-2026-64637 Privilege escalation in Plesk
Critical 9.9
Published
Updated
Check this codebase for CVE-2026-64637 and fix it if it is affected.
What it is: CVE-2026-64637 is a critical vulnerability in WebPros Plesk, published on 7 Aug 2026. Any signed-in user can exploit it over the network, with no action from the victim.
Exploitation: There is no known exploitation of CVE-2026-64637 in the wild and no public exploit code.
Affected product: WebPros Plesk. 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-2026-64637/ (Markdown: https://insights.sbomify.com/CVE-2026-64637/index.md)
An authenticated reseller can escalate privileges to obtain an administrative root session via the XML-RPC API in Plesk.
- Exploited in the wild
- Not known
- Login needed
- Any signed-in user
- Attackable
- Over the internet
- Victim action needed
- Not needed
- Fix
- None listed
What is CVE-2026-64637?
CVE-2026-64637 is a critical vulnerability in WebPros Plesk, published on 7 Aug 2026. Any signed-in user can exploit it over the network, with no action from the victim.
Official description
Improper privilege management in the XML-RPC API of Plesk before 18.0.80, allows an authenticated reseller to obtain an administrative session for the root user account.
Weakness: CWE-269
Which versions are affected by CVE-2026-64637?
How do I fix CVE-2026-64637?
No fix has been published for CVE-2026-64637 yet. Limit exposure of the affected software until one is available.
Is CVE-2026-64637 being exploited?
There is no known exploitation of CVE-2026-64637 in the wild and no public exploit code.
Sources
Also known as GHSA-27h3-c9gv-83jx.