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 |
|---|---|---|---|---|
| 7.1 | High | 4.0 | CVSS:4.0/AV:N/AC:L/AT:N/PR:L/UI:N/VC:H/VI:N/VA:L/SC:N/SI:N/SA:N | CNA (GitHub_M) |
- CISA KEV Not listed.
- EPSS 0.0034, the 27th percentile, on 5 Nov 2026: FIRST’s estimate of the chance of exploitation in the next 30 days.
Timeline
- 31 Oct 2026, 14:13 UTC First seen by agentprime
- 31 Oct 2026, 14:13 UTC Confirmed by OSV
Sources
- GitHub Advisory Database: GHSA-hwr4-mq23-wcv5
- OSV: GHSA-hwr4-mq23-wcv5
- github.com/dunglas/mercure/security/advisories/GHSA-hwr4-mq23-wcv5
- nvd.nist.gov/vuln/detail/CVE-2026-39972
- github.com/dunglas/mercure/commit/4964a69be904fd61e35b5f1e691271663b6fdd64
- github.com/dunglas/mercure
- github.com/dunglas/mercure/releases/tag/v0.22.0