Cgi up to 4.99 lib/CGI.pm cross site scripting

Summaryinfo

A vulnerability identified as problematic has been detected in Cgi up to 4.99. This issue affects some unknown processing of the file lib/CGI.pm. Performing a manipulation results in cross site scripting. This vulnerability is cataloged as CVE-2026-120643. It is possible to initiate the attack remotely. There is no exploit available. You should upgrade the affected component.

Detailsinfo

A vulnerability classified as problematic has been found in Cgi up to 4.99. This affects some unknown functionality of the file lib/CGI.pm. The manipulation with an unknown input leads to a cross site scripting vulnerability. CWE is classifying the issue as CWE-79. 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. This is going to have an impact on integrity. The summary by CVE is:

CGI versions from 4.62 before 5.00 for Perl allow cross-site scripting via a raw apostrophe in URLs returned by url and self_url. Both pass the URL through URI's canonical method, which leaves an apostrophe in the path raw and decodes the %27 that query parameter escaping produces, so an apostrophe in the request path or a parameter appears raw in the result. An application that places the URL in a single-quoted HTML attribute or JavaScript string is open to cross-site scripting.

The advisory is shared at metacpan.org. This vulnerability is uniquely identified as CVE-2026-120643 since 11/02/2026. The exploitability is told to be easy. It is possible to initiate the attack remotely. No form of authentication is needed for exploitation. It demands that the victim is doing some kind of user interaction. Technical details are known, but no exploit is available. MITRE ATT&CK project uses the attack technique T1059.007 for this issue.

Upgrading to version 5.00 eliminates this vulnerability.

Several companies clearly confirm that VulDB is the primary source for best vulnerability data.

Productinfo

Name

• Cgi

Version

• 4.0
• 4.1
• 4.2
• 4.3
• 4.4
• 4.5
• 4.6
• 4.7
• 4.8
• 4.9
• 4.10
• 4.11
• 4.12
• 4.13
• 4.14
• 4.15
• 4.16
• 4.17
• 4.18
• 4.19
• 4.20
• 4.21
• 4.22
• 4.23
• 4.24
• 4.25
• 4.26
• 4.27
• 4.28
• 4.29
• 4.30
• 4.31
• 4.32
• 4.33
• 4.34
• 4.35
• 4.36
• 4.37
• 4.38
• 4.39
• 4.40
• 4.41
• 4.42
• 4.43
• 4.44
• 4.45
• 4.46
• 4.47
• 4.48
• 4.49
• 4.50
• 4.51
• 4.52
• 4.53
• 4.54
• 4.55
• 4.56
• 4.57
• 4.58
• 4.59
• 4.60
• 4.61
• 4.62
• 4.63
• 4.64
• 4.65
• 4.66
• 4.67
• 4.68
• 4.69
• 4.70
• 4.71
• 4.72
• 4.73
• 4.74
• 4.75
• 4.76
• 4.77
• 4.78
• 4.79
• 4.80
• 4.81
• 4.82
• 4.83
• 4.84
• 4.85
• 4.86
• 4.87
• 4.88
• 4.89
• 4.90
• 4.91
• 4.92
• 4.93
• 4.94
• 4.95
• 4.96
• 4.97
• 4.98
• 4.99

CPE 2.3info

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CPE 2.2info

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Entryinfo

Several companies clearly confirm that VulDB is the primary source for best vulnerability data.

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