CVE-2019-12250 json
IdentityServer IdentityServer4 through 2.4 has stored XSS via the httpContext to the host/Extensions/RequestLoggerMiddleware.cs LogForError…
published 2019-05-21 7 y ago modified 2026-06-17 4 mo ago also EUVD-2019-3892
- cvss
- 6.1
- version 3.0, NVD
- cisa kev
- Not listed
- not in CISA's catalog
- epss
- 0.8%
- EPSS 0.8% chance of exploitation in 30 days, percentile 58%
- public exploits
- 0
- none known
Summary
IdentityServer IdentityServer4 through 2.4 has stored XSS via the httpContext to the host/Extensions/RequestLoggerMiddleware.cs LogForErrorContext method, which can be triggered by viewing a log. NOTE: the software maintainer disputes that this is a vulnerability because the request logger is not part of IdentityServer but only our development test host
Exploit prediction
0.85% chance of exploitation in the next 30 days, higher than 58% of all scored CVEs (FIRST EPSS, 2026-11-08).
Exploits and checks
- github.com https://github.com/IdentityServer/IdentityServer4/issues/3279 referenced PoC, tagged "exploit" by a source, unverified
CVSS scores
| assigned by | version | score | vector |
|---|---|---|---|
| NVD | 3.0 | 6.1 | CVSS:3.0/AV:N/AC:L/PR:N/UI:R/S:C/C:L/I:L/A:N |
| NVD | 2.0 | 4.3 | AV:N/AC:M/Au:N/C:N/I:P/A:N |
Classification
- Weakness
-
- CWE-79 Improper Neutralization of Input During Web Page Generation
References
-
github.com
/IdentityServer/IdentityServer4/issues/3279
exploit, third-party-advisory
Sources
- CVE List CVE-2019-12250
- NVD CVE-2019-12250
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