CVE-2025-2123: Geshi/geshi Cross-Site Scripting Vulnerability

MODERATE
Advisory Identifier: GHSA-pr6q-g5gv-qgr7
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CVSS 3.5
CWE-79
Published
Advisory Summary

CVE-2025-2123 is a MODERATE (CVSS 3.5) cross-site scripting vulnerability (CWE-79: Improper Neutralization of Input During Web Page Generation ('Cross-site Scripting')) affecting Geshi/geshi libraries in the Packagist ecosystem. The issue involves geshi xss possible in the get_var function of /contrib/cssgen.php. Remediation is available in the latest vendor maintenance releases.

CVE-2025-2123 at a Glance

CVE Identifier CVE-2025-2123
GHSA Identifier GHSA-pr6q-g5gv-qgr7
Severity MODERATE
CVSS v3.1 Base Score 3.5
CWE Classification CWE-79: Improper Neutralization of Input During Web Page Generation ('Cross-site Scripting')
Affected Product Geshi/geshi
Package Ecosystem Packagist
Published Date
Last Updated

Security Impact

CVSS: 3.5

The security impact metrics below are parsed directly from the CVSS v3.1 vector string (CVSS:3.1/AV:N/AC:L/PR:L/UI:R/S:U/C:N/I:L/A:N).

Attack Vector Network (AV:N)
Attack Complexity Low (AC:L)
Privileges Required Low (PR:L)
User Interaction Required (UI:R)
Scope Unchanged (S:U)
Confidentiality None (C:N)
Integrity Low (I:L)
Availability None (A:N)

How to Fix CVE-2025-2123

To remediate this vulnerability, upgrade all affected Geshi/geshi dependencies to a patched release. Both direct and transitive dependencies should be checked, as frameworks or security libraries may pull in vulnerable versions transitively.

geshi/geshi fixed: Latest secure release 
Upgrade geshi/geshi to Latest secure release
Verify Direct and Transitive Dependencies

Run the following command in your project directory to verify that all resolved dependencies use the patched release: 

inspect dependencies for geshi/geshi

How to Check if You Are Affected

To determine whether your application is affected by CVE-2025-2123, inspect your project dependencies for Geshi/geshi:

inspect dependencies for geshi/geshi

Analyze the terminal output to locate any version of Geshi/geshi in your dependency tree. If any resolved version matches the vulnerable ranges listed in the table below (for example, versions earlier than the patched release), your application is affected.

Note: Verify declared build manifests and deployed runtime container environments.

Technical Details

Vulnerability Mechanism & Technical Analysis

This vulnerability is classified under CWE-79: Improper Neutralization of Input During Web Page Generation ('Cross-site Scripting'), where the product does not neutralize or incorrectly neutralizes user-controllable input before it is placed in output that is used as a web page that is served to other users. In Geshi/geshi, software state validation or input boundaries are circumvented during processing. Review the official source advisory statement below for specific affected components, classes, and reproduction details.

Source Advisory Statement

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

CVE-2025-2123 Affected Geshi/geshi Versions

1 component(s)
Product / Package Ecosystem Affected Versions Fixed Version
geshi/geshi
 Packagist
≤ 1.0.9.1

References

NVD — CVE-2025-2123 NVD
https://nvd.nist.gov/vuln/detail/CVE-2025-2123
Geshi/geshi Source Repository REPOSITORY
https://github.com/GeSHi/geshi-1.0/issues/159
Geshi/geshi Source Repository REPOSITORY
https://github.com/GeSHi/geshi-1.0
vuldb.com/ WEB
https://vuldb.com/?ctiid.299036
vuldb.com/ WEB
https://vuldb.com/?id.299036
vuldb.com/ WEB
https://vuldb.com/?submit.507418

Frequently Asked Questions

What is CVE-2025-2123?
CVE-2025-2123 is a security vulnerability in Geshi/geshi involving GeSHi XSS possible in the get_var function of /contrib/cssgen.php under CWE-79: Improper Neutralization of Input During Web Page Generation ('Cross-site Scripting').
Which Geshi/geshi versions are affected?
Affected versions include releases prior to current release patches across affected packages: geshi/geshi.
What version fixes CVE-2025-2123?
Upgrading to current release patches (or the latest patched release for your respective branch) resolves the vulnerability.
Is geshi/geshi affected?
Yes, geshi/geshi is affected in releases prior to Latest secure release. Upgrade your dependency to Latest secure release or later.
What is the CVSS score of CVE-2025-2123?
CVE-2025-2123 has a CVSS v3.1 base score of 3.5 (MODERATE) with vector string CVSS:3.1/AV:N/AC:L/PR:L/UI:R/S:U/C:N/I:L/A:N.
What CWE is associated with CVE-2025-2123?
CVE-2025-2123 is classified under CWE-79: Improper Neutralization of Input During Web Page Generation ('Cross-site Scripting') (The product does not neutralize or incorrectly neutralizes user-controllable input before it is placed in output that is used as a web page that is served to other users.).
How can I check Packagist dependencies for CVE-2025-2123?
Run the dependency tree command: 'inspect dependencies for geshi/geshi'. This command lists direct and transitive dependencies in your build configuration so you can verify if a vulnerable version is resolved.
Machine-readable OSV JSON OSV v1.5 Schema
Normalized schema output
View Raw JSON 
{
  "schema_version" : "1.4.0",
  "id" : "GHSA-pr6q-g5gv-qgr7",
  "modified" : "2025-06-23T22:42:17Z",
  "published" : "2025-03-09T15:31:20Z",
  "aliases" : [ "CVE-2025-2123" ],
  "summary" : "GeSHi XSS possible in the get_var function of /contrib/cssgen.php",
  "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 cross site scripting. The attack may be launched remotely. The exploit has been disclosed to the public and may be used.",
  "severity" : [ {
    "type" : "CVSS_V3",
    "score" : "CVSS:3.1/AV:N/AC:L/PR:L/UI:R/S:U/C:N/I:L/A:N"
  }, {
    "type" : "CVSS_V4",
    "score" : "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"
  } ],
  "affected" : [ {
    "package" : {
      "ecosystem" : "Packagist",
      "name" : "geshi/geshi"
    },
    "ranges" : [ {
      "type" : "ECOSYSTEM",
      "events" : [ {
        "introduced" : "0"
      }, {
        "last_affected" : "1.0.9.1"
      } ]
    } ]
  } ],
  "references" : [ {
    "type" : "ADVISORY",
    "url" : "https://nvd.nist.gov/vuln/detail/CVE-2025-2123"
  }, {
    "type" : "WEB",
    "url" : "https://github.com/GeSHi/geshi-1.0/issues/159"
  }, {
    "type" : "PACKAGE",
    "url" : "https://github.com/GeSHi/geshi-1.0"
  }, {
    "type" : "WEB",
    "url" : "https://vuldb.com/?ctiid.299036"
  }, {
    "type" : "WEB",
    "url" : "https://vuldb.com/?id.299036"
  }, {
    "type" : "WEB",
    "url" : "https://vuldb.com/?submit.507418"
  } ],
  "database_specific" : {
    "cwe_ids" : [ "CWE-79" ],
    "severity" : "MODERATE",
    "github_reviewed" : true,
    "github_reviewed_at" : "2025-06-23T22:42:17Z",
    "nvd_published_at" : "2025-03-09T15:15:36Z"
  }
}