CVE-2026-50630
Apache Cxf ≤ 4.1.7
Raw vector
CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:L/I:L/A:NSummary
CVE-2026-50630 is a medium-severity HTTP Request/Response Splitting (CWE-113) vulnerability in Apache Cxf. Its CVSS base score is 6.5 (Medium).
Operationally, exploitation aligns with the MITRE ATT&CK technique Exploit Public-Facing Application (T1190); ranked at the 33th percentile by exploit likelihood (below the median); it is not currently listed in the CISA KEV catalog.
The strongest mitigations our analysis identified map to SI-10 (Information Input Validation) and AC-4 (Information Flow Enforcement) — see the control section below for these in your framework.
OWASP Top 10 for Web (2025)
EU & UK References
- 🇪🇺 ENISA EUVD: EUVD-2026-36398
Vulnerability Data
A CRLF injection vulnerability exists in the OAuth2 AuthorizationUtils class. When constructing the WWW-Authenticate response header, the 'realm' parameter is concatenated without sanitizing Carriage Return (CR) and Line Feed (LF) characters. If an attacker can control the realm value, they…
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can inject arbitrary HTTP headers or split the HTTP response entirely. Users are recommended to upgrade to versions 4.2.2 or 4.1.7, which fixes this issue.
- CWE(s)
Related Threats
MITRE ATT&CK Enterprise TechniquesAI
Why these techniques?
CRLF injection in OAuth2 header construction directly enables exploitation of public-facing web apps via crafted realm values.
CVEs Like This One
Affected Assets
Mitigating Controls
Control response
Mitigating Controls (NIST 800-53 r5) AI
Directly requires validation and sanitization of untrusted input (the realm parameter) before it is concatenated into the WWW-Authenticate header, blocking CRLF injection.
Enforces information flow rules that can reject or sanitize HTTP header values containing disallowed CR/LF characters before they reach the response.
Enables monitoring and anomaly detection on outgoing HTTP responses for unexpected header content or response-splitting patterns indicative of this injection.
Mitigating Controls (NIST CSF 2.0) AI
Derived directly from the weakness types (CWEs) cited in the NVD entry via our AI-authored CWE→CSF cross-walk (authority under review) — links open the control.
Secure SDLC practices directly require input sanitization and header handling that prevent CRLF injection.
Mitigating Controls (ISO/IEC 27001:2022 Annex A) AI
Derived directly from the weakness types (CWEs) cited in the NVD entry via our AI-authored CWE→ISO cross-walk (authority under review) — links open the control.
Security testing in development and acceptance can detect CRLF injection flaws before deployment.
Secure development lifecycle mandates input validation and output encoding that directly prevents CRLF injection into HTTP headers.
Application security requirements explicitly call for controls against injection flaws including HTTP header manipulation.
Secure architecture principles reduce the likelihood of header-splitting vulnerabilities through proper component isolation.
Secure coding standards require neutralization of CRLF sequences before inclusion in HTTP headers.
Logging of HTTP traffic can record header-splitting attempts, aiding detection and forensics.