CVE-2026-50188
CVE-2026-50188 — Kirby: Request header injection in `Http\Remote`
Kirby is an open-source content management system. Prior to 4.9.4 and 5.4.4, Kirby sites and plugins using the Kirby Http Remote class, including Remote::request(), Remote::get(), and Remote::post(), to send outgoing HTTP requests with untrusted data in the headers option could allow newline characters in a header value to inject a separate unintended request header to the remote service. This issue is fixed in versions 4.9.4 and 5.4.4.
Published Updated Sources: cvelistV5, GitHub_M
Triage
Is it exploited, how likely is exploitation, what does it touch, and how severe do the scoring sources call it.
Exploitation
Unreported
no source claims exploitation
EPSS
0%
chance of exploitation in 30 days
CVSS base
6.9
MEDIUM
CISA SSVC assessment
Three decision points CISA publishes for the CVEs it assesses · SSVC 2.0.3. A stakeholder decision, not a severity score.
Exploitation
None
none · proof-of-concept · active
Automatable
No
can an attacker script all four kill-chain steps
Technical impact
Partial
partial · total control of the vulnerable component
Affected scope
The catalog records vendors and products as separate lists, not pairs, so which product belongs to which vendor is not something this page can say.
Vendors (1)
Products (1)
Every base score collected
Sources score independently and disagree; each row says who scored it and under which version.
| Score | Version | Severity | Expl. | Impact | Source |
|---|---|---|---|---|---|
| 6.9 | CVSS 4.0 | MEDIUM | — | — | cvelistV5 |
Weakness & attack patterns
- CWE-93
- CWE-113
Attack patterns reported against this CVE. The ATT&CK techniques below are inferred from its weakness class.
- T1539Steal Web Session Cookie
References
5 on the record
- github.com/getkirby/kirby/security/advisories/GHSA-4v4h-m2qq-ppgw
x_refsource_CONFIRM
- github.com/getkirby/kirby/commit/aa33414e1669e866cdd6f4decfae2a669e8bb828
x_refsource_MISC
- github.com/getkirby/kirby/commit/fad9cbd22c73ed0fbd3aaf62310a8dcacfc007cd
x_refsource_MISC
- github.com/getkirby/kirby/releases/tag/4.9.4
x_refsource_MISC
- github.com/getkirby/kirby/releases/tag/5.4.4
x_refsource_MISC
Elsewhere on this site
Not in any source we poll
Listed rather than left blank: an empty field and an unmeasured one look identical on screen, and only one is a reason to look elsewhere.
- No confirmed IOCs, IP addresses, domains, file hashes, or malware artifacts supplied.
- No organization-specific asset inventory, compensating-control status, or patch deployment evidence supplied.
- No exploit packet captures, log samples, or incident case IDs supplied.