CVE-2026-120638
No CVSS score yet. EPSS 0.2% estimated probability of exploitation activity in the next 30 days.
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CGI versions before 5.00 for Perl allow open redirects via HTML entity decoding of the URL after application validation in redirect.
redirect decodes HTML entities in its URL before writing the Location header, so a URL the application has already validated can change meaning. For example, //evil.example/ becomes //evil.example/ and sends the user to another host.
- EPSS
- 0.2% estimated probability of exploitation activity in the next 30 days; 8th percentile. Scored 2026-11-04. A forecast for this CVE across the internet, not for your own systems.
- CWEs
- CWE-180 Incorrect Behavior Order: Validate Before Canonicalize
CWE-601 URL Redirection to Untrusted Site (Open Redirect) - OWASP Top 10
- A01:2025 Broken Access Control
- Published
- Modified
- Record from
- the NVD, synced
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Explain CVE-2026-120638 for an engineer deciding whether to act. Use https://cve.bz/api/public/cves/CVE-2026-120638?via=ask-ai-copy and https://cve.bz/cve/CVE-2026-120638?via=ask-ai-copy as the source of truth: what is affected and which versions fix it, whether it is in CISA KEV, public exploits, and its EPSS (an internet-wide 30-day estimate of exploitation activity, not a forecast for my systems). If they give no fixed versions, use the CVE record https://cveawg.mitre.org/api/cve/CVE-2026-120638 or the vendor advisory, not third-party mirrors. Tell me how to check whether I am affected and how to verify a fix. Cite the sources and say where they are uncertain.Opens a third-party assistant; its answer is its own, not cve.bz's. The prompt holds only this CVE's id and public links.
Linux distributions
| Distribution | Release | Package | Fixed in | Advisory |
|---|---|---|---|---|
| Debian | 12, 13, 14 | libcgi-pm-perl | no fix listed | DEBIAN-CVE-2026-120638 |
From the distributions' data via OSV.dev: the Debian Security Tracker. Modified: reformatted and linked to CVE records. Credits. On the distributions' own pages: Debian.
Attack patterns (CAPEC)
- CAPEC-178 Cross-Site Flashing Likelihood: Medium · Severity: Medium
- CAPEC-3 Using Leading 'Ghost' Character Sequences to Bypass Input Filters Likelihood: Medium · Severity: Medium
- CAPEC-71 Using Unicode Encoding to Bypass Validation Logic Likelihood: Medium · Severity: High
- CAPEC-78 Using Escaped Slashes in Alternate Encoding Likelihood: High · Severity: High
- CAPEC-79 Using Slashes in Alternate Encoding Likelihood: High · Severity: High
- CAPEC-80 Using UTF-8 Encoding to Bypass Validation Logic Likelihood: High · Severity: High
- CAPEC-267 Leverage Alternate Encoding Likelihood: High · Severity: High
The attack patterns MITRE's CAPEC relates to this record's weaknesses, as MITRE names them. Credits.