CVE-2026-45191 STIGTSP CVE debrief

Who should care

Users of Net::CIDR::Lite versions before 0.24 for Perl should be aware of this vulnerability as it may allow IP ACL bypass. This includes operators, platform administrators, vulnerability management teams, and security teams who need to assess and mitigate this vulnerability in their environments.

Technical summary

The vulnerability is caused by the library's improper handling of CIDR mask values with extraneous zero characters. This could lead to IP ACL bypass as certain mask forms are parsed to the same prefix as their unpadded value. The affected product is Net::CIDR::Lite versions before 0.24 for Perl. There are no known exploits, but defenders should be aware of the potential impact and plan for updates or mitigations.

Defensive priority

Medium priority should be given to updating Net::CIDR::Lite to version 0.24 or later to mitigate this vulnerability.

Recommended defensive actions

• Update Net::CIDR::Lite to version 0.24 or later
• Review and update IP ACL configurations
• Monitor for potential IP ACL bypass attempts
• Confirm whether affected product deployments exist in managed environments and assign an owner for follow-up
• Review compensating controls for exposed systems while remediation is scheduled and verified
• Check relevant monitoring, detection, and logs for exposed assets that need extra review
• Track exceptions, retest remediated assets, and close the item only after evidence is documented

Evidence notes

The CVE record was published on 2026-05-10T21:16:29.380Z and was last modified on 2026-07-24T13:10:00.223Z. The NVD entry is currently Deferred. Evidence is limited to public sources and may not reflect the full scope or impact of this vulnerability. Defenders should verify affected deployments and review official advisories for specific guidance.

Official resources