Machine-written summary
Summary written by Claude Haiku from the source advisory. Not reviewed by a person.
Lemur versions before 1.9.2 are vulnerable to server-side request forgery. When Lemur verifies an uploaded certificate, it sends outbound requests to CRL Distribution Point and OCSP responder URLs taken from the certificate's extensions, with no restriction on destination. An authenticated user with the operator role can upload a crafted certificate to make the Lemur host request internal addresses, such as cloud metadata endpoints or private network hosts. Upgrade to Lemur 1.9.2 or later. The source gives no workaround.
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 |
|---|---|---|---|---|
| 6.3 | Medium | 3.1 | CVSS:3.1/AV:N/AC:L/PR:L/UI:N/S:U/C:L/I:L/A:L | CNA (GitHub_M) |
- CISA KEV Not listed.
- EPSS 0.0022, the 12th percentile, on 12 Nov 2026: FIRST’s estimate of the chance of exploitation in the next 30 days.
Timeline
- 31 Oct 2026, 14:39 UTC First seen by agentprime
- 31 Oct 2026, 14:39 UTC Confirmed by OSV