Cyber Resilience

CVE-2025-66305

Getgrav Grav 1.7.48 – 1.8.0

Public PoC
Published
01 December 2025
Modified
03 December 2025
Patch / advisory
CVSS Score v4 6.9
Click a component to see what it means
Raw vectorCVSS:4.0/AV:N/AC:L/AT:N/PR:H/UI:N/VC:N/VI:N/VA:H/SC:N/SI:N/SA:N/E:X/CR:X/IR:X/AR:X/MAV:X/MAC:X/MAT:X/MPR:X/MUI:X/MVC:X/MVI:X/MVA:X/MSC:X/MSI:X/MSA:X/S:X/AU:X/R:X/V:X/RE:X/U:X
EPSS Score 0.0038 30th percentile
Risk Priority 35 floored blend · peak EPSS

Summary

CVE-2025-66305 is a medium-severity Uncaught Exception (CWE-248) vulnerability in Getgrav Grav. Its CVSS base score is 6.9 (Medium).

Operationally, exploitation aligns with the MITRE ATT&CK technique Application or System Exploitation (T1499.004); ranked at the 30th percentile by exploit likelihood (below the median); it is not currently listed in the CISA KEV catalog; a public proof-of-concept is referenced.

The strongest mitigations our analysis identified map to SI-10 (Information Input Validation) and SI-11 (Error Handling) — see the control section below for these in your framework.

OWASP Top 10 for Web (2025)

EU & UK References

Vulnerability Data

Grav is a file-based Web platform. Prior to 1.8.0-beta.27, a Denial of Service (DoS) vulnerability was identified in the "Languages" submenu of the Grav admin configuration panel (/admin/config/system). Specifically, the Supported parameter fails to properly validate user input. If a…

more

malformed value is inserted—such as a single forward slash (/) or an XSS test string—it causes a fatal regular expression parsing error on the server. This leads to application-wide failure due to the use of the preg_match() function with an improperly constructed regular expression, resulting in an error. Once triggered, the site becomes completely unavailable to all users. This vulnerability is fixed in 1.8.0-beta.27.

CWE(s)

Related Threats

MITRE ATT&CK Enterprise TechniquesAI

T1499.004 Application or System Exploitation Impact
Adversaries may exploit software vulnerabilities that can cause an application or system to crash and deny availability to users.
Why these techniques?

The vulnerability allows direct exploitation of improper input validation in preg_match() to trigger a fatal uncaught exception, crashing the application and denying service to all users (T1499.004).

Confidence: HIGH · MITRE ATT&CK Enterprise v19.0

CVEs Like This One

CVE-2025-66303Same product: Getgrav Grav
CVE-2023-34448Same product: Getgrav Grav
CVE-2025-46198Same product: Getgrav Grav
CVE-2025-66301Same product: Getgrav Grav
CVE-2023-34252Same product: Getgrav Grav
CVE-2023-34251Same product: Getgrav Grav
CVE-2024-35498Same product: Getgrav Grav
CVE-2024-28116Same product: Getgrav Grav
CVE-2026-42609Same product: Getgrav Grav
CVE-2023-34452Same product: Getgrav Grav

Affected Assets

getgrav
grav
1.8.0 · 1.7.48 — 1.8.0

Mitigating Controls

Control response

Prevent
Stop it (NIST 800-53)
  • SI-10 Information Input Validation
  • SI-11 Error Handling
  • SC-24 Fail in Known State
Detect
Catch it (NIST detect / respond)

Harden
Shrink the surface (DISA STIG)

Validate
Prove the fix (OWASP ASVS)

Mitigating Controls (NIST 800-53 r5) AI

prevent

Directly requires validation of all input to the Languages Supported parameter so that malformed values cannot reach preg_match().

prevent

Mandates graceful error handling that would catch the regex failure and keep the Grav application available instead of crashing site-wide.

prevent

Ensures the system fails to a known safe state rather than allowing an unhandled exception to render the entire platform unavailable.

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.

PR.PS-06 mostly match
prevents

Secure SDLC practices explicitly require structured exception handling to prevent uncaught exceptions from reaching production.

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.

detects

Security testing can detect uncaught exceptions before production deployment.

prevents

Secure development lifecycle includes exception-handling standards that reduce uncaught exceptions.

prevents

Application security requirements typically mandate robust error and exception handling.

prevents

Secure architecture principles call for centralized, comprehensive exception management.

prevents

Secure coding standards directly require catching and handling exceptions to prevent crashes or leaks.

References