Raw vector
CVSS:3.1/AV:N/AC:H/PR:H/UI:R/S:C/C:H/I:H/A:HCVSS and EPSS are reproduced from their sources (NVD, FIRST EPSS). Risk Priority is our own derived reading, not an NVD score.
Summary
CVE-2025-27405 is a high-severity Cross-site Scripting (CWE-79) vulnerability in Icinga Icinga Web 2. Its CVSS base score is 7.6 (High).
Operationally, exploitation aligns with the MITRE ATT&CK technique Browser Session Hijacking (T1185); ranked at the 24th 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 SA-11 (Developer Testing and Evaluation) and SI-10 (Information Input Validation) — see the control section below for these in your framework.
Deeper analysis AI-assisted summary
Synthesised by an AI model from the NVD description and linked references — a reading aid, not an authoritative source.
CVE-2025-27405 is a cross-site scripting (XSS) vulnerability (CWE-79) affecting Icinga Web 2, an open source monitoring web interface, framework, and command-line interface. Versions prior to 2.11.5 and 2.12.13 are vulnerable, enabling an attacker to craft a malicious URL that embeds arbitrary JavaScript into the Icinga Web interface when visited by a user. The vulnerability carries a CVSS v3.1 base score of 7.6 (AV:N/AC:H/PR:H/UI:R/S:C/C:H/I:H/A:H).
An attacker with high privileges (PR:H) can exploit this by crafting a URL that requires a user to visit it (UI:R), such as through social engineering like phishing or shared links. Once visited over the network (AV:N), the embedded JavaScript executes in the context of the victim's session, allowing the attacker to act on behalf of that user. This can lead to high confidentiality, integrity, and availability impacts (C:H/I:H/A:H) with elevated scope (S:C), potentially enabling unauthorized actions based on the victim's permissions.
The issue is resolved in Icinga Web 2 versions 2.11.5 and 2.12.3, as detailed in the project's release notes and security advisory (GHSA-3x37-fjc3-ch8w). As a workaround for version 2.12.2, administrators can enable a content security policy in the application settings. Security practitioners should prioritize patching affected installations and review access controls for privileged users.
OWASP Top 10 for Web (2025)
EU & UK References
- 🇪🇺 ENISA EUVD: EUVD-2025-8216
Vulnerability Data
Icinga Web 2 is an open source monitoring web interface, framework and command-line interface. A vulnerability in versions prior to 2.11.5 and 2.12.13 allows an attacker to craft a URL that, once visited by any user, allows to embed arbitrary…
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Javascript into Icinga Web and to act on behalf of that user. This issue has been resolved in versions 2.11.5 and 2.12.3 of Icinga Web 2. As a workaround, those who have Icinga Web 2.12.2 may enable a content security policy in the application settings.
- CWE(s)
Related Threats
MITRE ATT&CK Enterprise Techniques
CVEs Like This One
Affected Assets
Mitigating Controls
Control response
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V1.1.2V1.3.2
Mitigating Controls (NIST 800-53 r5) AI
Developer testing and evaluation can discover missing or incorrect input neutralization through targeted web-application tests.
Input validation directly enforces neutralization of untrusted data before it reaches web output generation.
Output filtering can catch or sanitize unneutralized script content before it is served to users.
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 target introduction of XSS via coding standards/testing (mostly), yet the single broad outcome leaves many specific neutralization vectors unaddressed (partial).
Patching and EOL replacement can remediate known XSS instances in libraries or frameworks (partial) but do nothing to enforce input neutralization in application code (none).
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.
Secure-coding testing and automated code-analysis tools are applied to detect improper neutralization of script-related content during web-page generation.
Knowledge exchange on emerging attack techniques and patches reduces the likelihood that cross-site scripting flaws remain unaddressed in deployed applications.
Operational indicators of compromise for web-application attacks can be incorporated into WAF or input-filtering rules, lowering the likelihood that unsanitized data reaches the browser.
Requiring language-specific secure-coding standards and automated scanning during the SDLC catches missing output encoding or improper neutralization of untrusted data before the software reaches production.
Secure-coding standards, SAST scans and removal of insecure code samples together eliminate the failure to neutralize script content that produces cross-site scripting flaws.