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Fencer Intel
low 3.5

CVE-2022-4891 json

Sisimai string.rb to_plain redos

published 3y ago modified 4mo ago also GHSA-vm74-j4wq-82xj , EUVD-2023-0562

cvss
3.5
version 3.1, CNA
cisa kev
Not listed
not in CISA's catalog
epss
1.4%
EPSS 1.4% chance of exploitation in 30 days, percentile 72%
public exploits
0
none known

Summary

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.

Patch / fix

  • rubygems sisimai 4.25.14p12
  • libsisimai sisimai 4.25.14

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Exploit prediction

1.39% chance of exploitation in the next 30 days, higher than 72% of all scored CVEs (FIRST EPSS, 2026-11-14).

Exploits and checks

  • github.com https://github.com/sisimai/rb-sisimai/pull/244 referenced PoC, tagged "exploit" by a source, unverified
  • gist.githubusercontent.com https://gist.githubusercontent.com/gmcabrita/e5dc0332473fc2e3a7a407434c8d21c7/raw/00b12035e5e1b685469f143b94301a50306376ba/example.html referenced PoC, tagged "exploit" by a source, unverified

CVSS scores

assigned by version score vector
CNA 3.1 3.5 CVSS:3.1/AV:A/AC:L/PR:L/UI:N/S:U/C:N/I:N/A:L
CNA 3.0 3.5 CVSS:3.0/AV:A/AC:L/PR:L/UI:N/S:U/C:N/I:N/A:L
CNA 2.0 2.7 AV:A/AC:L/Au:S/C:N/I:N/A:P
NVD 3.1 7.5 CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:H
GitHub 3.1 4.3 CVSS:3.1/AV:N/AC:L/PR:L/UI:N/S:U/C:N/I:N/A:L

Affected packages

ecosystem package affected fixed in
rubygems sisimai
<4.25.14p12
4.25.14p12

Affected products

  • n/a Sisimai

Classification

Weakness
  • CWE-1333 Inefficient Regular Expression Complexity

References

Sources

Fencer Intel keeps one entry per vulnerability: the CVE id wins, then GHSA, and records that alias each other are merged, except that two CVEs always keep separate entries. The same data is available as JSON.