Machine-written summary
Summary written by Claude Haiku from the source advisory. Not reviewed by a person.
Mautic (mautic/core) versions 5.1.0 before 5.1.1 are vulnerable to username enumeration through the login page. When a valid username is submitted with a weak password, the application reports that the password is too weak, but an invalid username with a weak password returns "Invalid credentials," letting an attacker tell which usernames exist. Upgrade to mautic/core 5.1.1 or later.
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 |
|---|---|---|---|---|
| 4.3 | Medium | 3.1 | CVSS:3.1/AV:N/AC:L/PR:L/UI:N/S:U/C:L/I:N/A:N | CNA (Mautic) |
- CISA KEV Not listed.
- EPSS 0.0034, the 27th percentile, on 8 Nov 2026: FIRST’s estimate of the chance of exploitation in the next 30 days.
Timeline
- 31 Oct 2026, 14:29 UTC First seen by agentprime
- 31 Oct 2026, 14:29 UTC Confirmed by OSV