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Fencer Intel
medium 6.5

CVE-2026-45191 json

Net::CIDR::Lite versions before 0.24 for Perl does not properly consider extraneous zero characters in CIDR mask values, which may allow IP ACL bypass

published 5mo ago modified 3mo ago also EUVD-2026-28999

cvss
6.5
version 3.1, CNA
cisa kev
Not listed
not in CISA's catalog
epss
0.3%
EPSS 0.3% chance of exploitation in 30 days, percentile 22%
public exploits
0
none known

Summary

Net::CIDR::Lite versions before 0.24 for Perl does not properly consider extraneous zero characters in CIDR mask values, which may allow IP ACL bypass.

Mask forms like "/00" and "/01" pass validation and parse to the same prefix as their unpadded value.

See also CVE-2026-45190.

Patch / fix

  • STIGTSP Net::CIDR::Lite 0.24
  • libnet-cidr-lite-perl Debian 12 0.22-3~deb12u2
  • libnet-cidr-lite-perl Debian 13 0.22-3~deb13u2
  • libnet-cidr-lite-perl Debian 14 0.24-1

debian advisories DEBIAN-CVE-2026-45191

  • libnet-cidr-lite-perl Ubuntu 22.04 LTS 0.22-1ubuntu0.2
  • libnet-cidr-lite-perl Ubuntu 24.04 LTS 0.22-2ubuntu0.24.04.2
  • libnet-cidr-lite-perl Ubuntu 25.10 0.22-2ubuntu0.25.10.2
  • libnet-cidr-lite-perl Ubuntu 26.04 LTS 0.22-2ubuntu0.26.04.2
  • libnet-cidr-lite-perl Ubuntu Pro 16.04 LTS 0.21-1ubuntu0.16.04.1~esm2
  • libnet-cidr-lite-perl Ubuntu Pro 18.04 LTS 0.21-1ubuntu0.18.04.1~esm2
  • libnet-cidr-lite-perl Ubuntu Pro 20.04 LTS 0.21-2ubuntu0.1+esm2

ubuntu advisories UBUNTU-CVE-2026-45191

Ubuntu security data © Canonical Ltd., from https://github.com/canonical/ubuntu-security-notices via OSV; changed: normalised to fixed package versions per release. CC BY-SA 4.0

  • perl-Net-CIDR-Lite openSUSE Tumbleweed 0.240.0-1.1

opensuse advisories openSUSE-SU-2026:10780-1

  • perl-net-cidr-lite Alpine 3.24 0.24-r0

alpine advisories ALPINE-CVE-2026-45191

Alpine secdb © Alpine Linux, from https://secdb.alpinelinux.org via OSV; changed: normalised to fixed package versions per release. CC BY-SA 4.0

Is CVE-2026-45191 in your stack? Fencer shows which of your repositories are affected as soon as an advisory lands, and opens the fix as a pull request.

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Vendor advisories

What the vendors themselves say about their products: affected, fixed or not affected, and what to do.

red hat product security vex CVE-2026-45191 updated cvss 6.5

perl-Net-CIDR-Lite: Net::CIDR::Lite: IP ACL bypass due to improper CIDR mask validation

  • Red Hat Enterprise Linux 9 perl-Net-CIDR-Lite
    affected: no fix available “Fix deferred”

Red Hat CSAF VEX © Red Hat, Inc., from https://security.access.redhat.com/data/csaf/v2/vex/; changed: reduced to product statuses and remediations. CC BY 4.0 · csaf

CISA SSVC

Exploitation
none
Automatable
yes
Technical impact
partial
Assessed
5mo ago

Exploit prediction

0.30% chance of exploitation in the next 30 days, higher than 22% of all scored CVEs (FIRST EPSS, 2026-11-09).

CVSS scores

assigned by version score vector
CISA ADP 3.1 6.5 CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:L/A:L
CNA 3.1 6.5 CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:L/A:L

Affected products

  • STIGTSP Net::CIDR::Lite

Classification

Weakness
  • CWE-1289 Improper Validation of Unsafe Equivalence in Input

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.

CPEs and fixed versions use Anchore's correction of NVD's data: Added CPE configurations because not yet analyzed by NVD.