Skip to content

Sisimai Inefficient Regular Expression Complexity vulnerability

Moderate severity GitHub Reviewed Published Jan 17, 2023 to the GitHub Advisory Database • Updated Feb 17, 2026

Package

bundler sisimai (RubyGems)

Affected versions

< 4.25.14p12

Patched versions

4.25.14p12

Description

A vulnerability has been found in Sisimai up to 4.25.14p11 and classified as problematic. This vulnerability affects the function to_plain of the file lib/sisimai/string.rb. The manipulation leads to inefficient regular expression complexity. The exploit has been disclosed to the public and may be used. Upgrading to version 4.25.14p12 is able to address this issue. The name of the patch is 51fe2e6521c9c02b421b383943dc9e4bbbe65d4e. It is recommended to upgrade the affected component. The identifier of this vulnerability is VDB-218452.

References

Published by the National Vulnerability Database Jan 17, 2023
Published to the GitHub Advisory Database Jan 17, 2023
Reviewed Jan 20, 2023
Last updated Feb 17, 2026

Severity

Moderate

CVSS overall score

This score calculates overall vulnerability severity from 0 to 10 and is based on the Common Vulnerability Scoring System (CVSS).
/ 10

CVSS v3 base metrics

Attack vector
Network
Attack complexity
Low
Privileges required
Low
User interaction
None
Scope
Unchanged
Confidentiality
None
Integrity
None
Availability
Low

CVSS v3 base metrics

Attack vector: More severe the more the remote (logically and physically) an attacker can be in order to exploit the vulnerability.
Attack complexity: More severe for the least complex attacks.
Privileges required: More severe if no privileges are required.
User interaction: More severe when no user interaction is required.
Scope: More severe when a scope change occurs, e.g. one vulnerable component impacts resources in components beyond its security scope.
Confidentiality: More severe when loss of data confidentiality is highest, measuring the level of data access available to an unauthorized user.
Integrity: More severe when loss of data integrity is the highest, measuring the consequence of data modification possible by an unauthorized user.
Availability: More severe when the loss of impacted component availability is highest.
CVSS:3.1/AV:N/AC:L/PR:L/UI:N/S:U/C:N/I:N/A:L

EPSS score

Exploit Prediction Scoring System (EPSS)

This score estimates the probability of this vulnerability being exploited within the next 30 days. Data provided by FIRST.
(50th percentile)

Weaknesses

Inefficient Regular Expression Complexity

The product uses a regular expression with an inefficient, possibly exponential worst-case computational complexity that consumes excessive CPU cycles. Learn more on MITRE.

CVE ID

CVE-2022-4891

GHSA ID

GHSA-vm74-j4wq-82xj

Source code

Credits

Loading Checking history
See something to contribute? Suggest improvements for this vulnerability.