Not analysed yet
We haven’t published our analysis of this Advisory yet. Once a person has reviewed it, this page will say what’s vulnerable, what has to be true for your app to be affected, and how to check.
Severity and exploitation
| Score | Rating | CVSS | Vector | Source |
|---|---|---|---|---|
| 8.2 | High | 3.1 | CVSS:3.1/AV:N/AC:L/PR:N/UI:R/S:C/C:H/I:L/A:N | CNA (GitHub_M) |
- CISA KEV Not listed.
- EPSS 0.0019, the 9th percentile, on 6 Nov 2026: FIRST’s estimate of the chance of exploitation in the next 30 days.
Timeline
- 31 Oct 2026, 15:17 UTC First seen by agentprime
- 31 Oct 2026, 15:17 UTC Confirmed by OSV
Sources
- GitHub Advisory Database: GHSA-33f5-2c5q-wgwj
- OSV: GHSA-33f5-2c5q-wgwj
- github.com/modelcontextprotocol/rust-sdk/security/advisories/GHSA-33f5-2c5q-wgwj
- nvd.nist.gov/vuln/detail/CVE-2026-63127
- github.com/modelcontextprotocol/rust-sdk/pull/937
- github.com/modelcontextprotocol/rust-sdk/commit/c1a8b29ff2cc45e7820b900dae42cbb4958089ec
- github.com/modelcontextprotocol/rust-sdk
- github.com/modelcontextprotocol/rust-sdk/releases/tag/rmcp-v2.0.0