CVE-2026-46608 Glances: XML-RPC Multi-Origin CORS Configuration Silently Falls Back to Wildcard (Incomplete Fix for CVE-2026-33533)
Glances XML-RPC server incorrectly applies wildcard CORS when multiple origins are configured, allowing malicious sites to read system monitoring data.
- 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
What is CVE-2026-46608?
CVE-2026-46608 is a high-severity vulnerability in nicolargo glances, published on 25 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
Glances is an open-source system cross-platform monitoring tool. Prior to 4.5.5, the Glances XML-RPC server (glances -s) introduced a configurable CORS origin list in version 4.5.3 as a mitigation for CVE-2026-33533. However, the implementation silently falls back to Access-Control-Allow-Origin: * whenever cors_origins contains more than one entry. An operator who configures an explicit two-entry allowlist (e.g. two internal dashboard origins) intending to restrict browser access instead receives the unrestricted wildcard. A malicious web page served from any origin can issue a CORS simple request to /RPC2 and read the full system monitoring dataset without the victim's knowledge. This vulnerability is fixed in 4.5.5.
Which versions are affected by CVE-2026-46608?
3 open source packages ship an affected version, including glances.
| Package | Affected | Fixed in |
|---|---|---|
glances PyPI | All versions | 4.5.5 |
glances PyPI | All versions | 4.5.5 |
glances PyPI | All versions | 4.5.5 |
How do I fix CVE-2026-46608?
Upgrade glances to 4.5.5 or later.
Is CVE-2026-46608 being exploited?
There is no known exploitation of CVE-2026-46608 in the wild and no public exploit code.
Sources
Also known as DEBIAN-CVE-2026-46608, GHSA-87qc-fj39-wccr, PYSEC-2026-2495, UBUNTU-CVE-2026-46608.