Cyber Resilience

CVE-2025-2123

MediumPublic PoC

Published: 09 March 2025

Published
09 March 2025
Modified
23 June 2025
KEV Added
Patch
CVSS Score v4 5.1 CVSS:4.0/AV:N/AC:L/AT:N/PR:L/UI:P/VC:N/VI:L/VA:N/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 0.0019 41.2th percentile
Risk Priority 10 60% EPSS · 20% KEV · 20% CVSS

Summary

CVE-2025-2123 is a medium-severity Cross-site Scripting (CWE-79) vulnerability in Qbnz Geshi. Its CVSS base score is 5.1 (Medium).

Operationally, exploitation aligns with the MITRE ATT&CK technique Exploit Public-Facing Application (T1190); ranked at the 41.2th percentile by exploit likelihood (below the median); it is not currently listed in the CISA KEV catalog; a public proof-of-concept is referenced.

EU & UK References

Vulnerability details

A vulnerability, which was classified as problematic, has been found in GeSHi up to 1.0.9.1. Affected by this issue is the function get_var of the file /contrib/cssgen.php of the component CSS Handler. The manipulation of the argument default-styles/keywords-1/keywords-2/keywords-3/keywords-4/comments leads to…

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cross site scripting. The attack may be launched remotely. The exploit has been disclosed to the public and may be used.

CWE(s)

Related Threats

MITRE ATT&CK Enterprise TechniquesAI

T1190 Exploit Public-Facing Application Initial Access
Adversaries may attempt to exploit a weakness in an Internet-facing host or system to initially access a network.
T1059.007 JavaScript Execution
Adversaries may abuse various implementations of JavaScript for execution.
T1539 Steal Web Session Cookie Credential Access
An adversary may steal web application or service session cookies and use them to gain access to web applications or Internet services as an authenticated user without needing credentials.
Why these techniques?

Reflected XSS in public-facing cssgen.php enables exploitation of public-facing web applications (T1190), arbitrary JavaScript execution in victim browsers (T1059.007), and stealing web session cookies as shown in POC (T1539).

Affected Assets

qbnz
geshi
≤ 1.0.9.1

Mitigating Controls

Likely Mitigating Controls AI

Per-CVE control mapping for this CVE has not run yet; the list below is derived from the weakness types (CWEs) cited in the NVD entry.

addresses: CWE-79 CWE-94

Validates web inputs to reject script-related content that could produce XSS.

addresses: CWE-79

Penetration testing submits XSS payloads to web applications, detecting cross-site scripting flaws for subsequent remediation.

addresses: CWE-94

Makes persistent code injection into loaded programs impossible when the executable image itself resides on hardware-protected read-only media.

addresses: CWE-94

Dynamically generated code can be produced and executed inside the isolated chamber, preventing host compromise from code-injection payloads.

addresses: CWE-79

Output validation against expected content can reject or sanitize script content in generated web pages, reducing XSS exploitability.

addresses: CWE-94

Directly prevents execution of attacker-supplied code written into data memory regions.

References