Machine-written summary
Summary written by Claude Haiku from the source advisory. Not reviewed by a person.
Spring Security Web versions >=6.5.0 <6.5.11, >=6.4.0 <=6.4.13, >=6.0.0 <=6.3.10, >=5.8.0 <=5.8.16, and <=5.7.14 are affected. The SubjectDnX509PrincipalExtractor class can read the wrong username from certain malformed certificate CN values, so an attacker holding a specially crafted X.509 client certificate may be able to impersonate another user. Upgrade to 6.5.11 or later. Migrating to SubjectX500PrincipalExtractor is also recommended, since SubjectDnX509PrincipalExtractor is deprecated by this CVE.
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 |
|---|---|---|---|---|
| 6.8 | Medium | 3.1 | CVSS:3.1/AV:N/AC:H/PR:L/UI:N/S:U/C:H/I:H/A:N | CNA (vmware) |
- CISA KEV Not listed.
- EPSS 0.0013, the 2nd percentile, on 9 Nov 2026: FIRST’s estimate of the chance of exploitation in the next 30 days.
Timeline
- 31 Oct 2026, 14:16 UTC First seen by agentprime
- 31 Oct 2026, 14:16 UTC Confirmed by OSV