How severe is CVE-2025-27220?

CVE-2025-27220 has a CVSS 3.x base score of 4.0, rated medium severity. It is exploitable over network with high attack complexity, requires no privileges and no user interaction. Impact on confidentiality is none, integrity none, and availability low.

Is CVE-2025-27220 being actively exploited?

It is not currently listed in CISA's KEV catalog. Its EPSS exploit-prediction score is 1% (49th percentile), an estimate of the probability of exploitation in the next 30 days.

What products are affected by CVE-2025-27220?

CVE-2025-27220 primarily affects Ruby-lang Cgi. In total, 2 product configurations (CPEs) are listed as vulnerable; see the affected-products list for the exact versions.

How do I fix CVE-2025-27220?

Review the linked vendor and NVD advisories for patched versions and mitigations, then upgrade or apply the recommended workaround.

Does CVE-2025-27220 have an EU (EUVD) identifier?

Yes. CVE-2025-27220 is tracked in the ENISA EU Vulnerability Database (EUVD) as EUVD-2025-5509.

When was CVE-2025-27220 published?

CVE-2025-27220 was published on 2025-03-04 and last updated on 2026-06-17.

CVE-2025-27220

CVE-2025-27220 is a medium-severity vulnerability in Ruby-lang Cgi with a CVSS 3.x base score of 4.0. It is not currently listed as actively exploited by CISA, and its EPSS exploit-prediction score is low. The underlying weakness is classified as CWE-1333.

Key facts

Severity: Medium (CVSS 3.x base score 4.0)
EPSS exploit prediction: 1% (49th percentile)
Actively exploited: Not listed in CISA KEV
EU (EUVD) id: EUVD-2025-5509
Weakness: CWE-1333
Affected product: Ruby-lang Cgi
Published: 2025-03-04
Last modified: 2026-06-17

Description

In the CGI gem before 0.4.2 for Ruby, a Regular Expression Denial of Service (ReDoS) vulnerability exists in the Util#escapeElement method.

Frequently asked questions

What is CVE-2025-27220?: In the CGI gem before 0.4.2 for Ruby, a Regular Expression Denial of Service (ReDoS) vulnerability exists in the Util#escapeElement method.
How severe is CVE-2025-27220?: CVE-2025-27220 has a CVSS 3.x base score of 4.0, rated medium severity. It is exploitable over network with high attack complexity, requires no privileges and no user interaction. Impact on confidentiality is none, integrity none, and availability low.
Is CVE-2025-27220 being actively exploited?: It is not currently listed in CISA's KEV catalog. Its EPSS exploit-prediction score is 1% (49th percentile), an estimate of the probability of exploitation in the next 30 days.
What products are affected by CVE-2025-27220?: CVE-2025-27220 primarily affects Ruby-lang Cgi. In total, 2 product configurations (CPEs) are listed as vulnerable; see the affected-products list for the exact versions.
How do I fix CVE-2025-27220?: Review the linked vendor and NVD advisories for patched versions and mitigations, then upgrade or apply the recommended workaround.
Does CVE-2025-27220 have an EU (EUVD) identifier?: Yes. CVE-2025-27220 is tracked in the ENISA EU Vulnerability Database (EUVD) as EUVD-2025-5509.
When was CVE-2025-27220 published?: CVE-2025-27220 was published on 2025-03-04 and last updated on 2026-06-17.

References

Affected products (2)

cpe:2.3:a:ruby-lang:cgi:*:*:*:*:*:ruby:*:*
cpe:2.3:a:ruby-lang:cgi:0.3.6:*:*:*:*:ruby:*:*

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