# CVE-2026-45190: Security feature bypass in Net::CIDR::Lite

> Attackers can bypass IP-based access controls in applications using Net::CIDR::Lite by exploiting improper input validation of IP addresses and CIDR masks.

- **Severity:** Medium 6.5 (`CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:L/A:L`)
- **Exploited in the wild:** Not known
- **Login needed:** Not needed
- **Attackable:** Over the internet
- **Victim action needed:** Not needed
- **Fix available:** Yes
- **Published:** 10 May 2026
- **Updated:** 12 May 2026
- **Also known as:** ALPINE-CVE-2026-45190, AZL-86414, DEBIAN-CVE-2026-45190, GHSA-5vf8-328m-mxj5, UBUNTU-CVE-2026-45190

## What is CVE-2026-45190?

CVE-2026-45190 is a medium-severity vulnerability in STIGTSP Net::CIDR::Lite, published on 10 May 2026. An attacker can exploit it over the internet without logging in, with no action from the victim.

### Official description

Net::CIDR::Lite versions before 0.24 for Perl does not properly validate IP address and CIDR mask inputs, which may allow IP ACL bypass.

Inputs containing a trailing newline or non-ASCII digit characters pass the validators but are then re-encoded by the parser to a different address than the input string spelled. find() and bin_find() can match or miss addresses as a result.

Example:

  my $cidr = Net::CIDR::Lite->new();
  $cidr->add("::1\n/128");
  $cidr->find("::1a");  # incorrectly returns true

See also CVE-2026-45191.

Weakness: CWE-1289 (Improper Validation of Unsafe Equivalence in Input)

## Which versions are affected by CVE-2026-45190?


## How do I fix CVE-2026-45190?

Upgrade to a fixed version.

## Is CVE-2026-45190 being exploited?

There is no known exploitation of CVE-2026-45190 in the wild and no public exploit code.

## Fix prompt for AI coding agents

```text
Check this codebase for CVE-2026-45190 and fix it if it is affected.

What it is: CVE-2026-45190 is a medium-severity vulnerability in STIGTSP Net::CIDR::Lite, published on 10 May 2026. An attacker can exploit it over the internet without logging in, with no action from the victim.
Exploitation: There is no known exploitation of CVE-2026-45190 in the wild and no public exploit code.

Affected product: STIGTSP Net::CIDR::Lite. No package-level version data is available, so check the vendor advisory linked from the reference page.

Task:
1. Search the dependency manifests and lockfiles (for example package.json, package-lock.json, requirements.txt, poetry.lock, uv.lock, pom.xml, build.gradle, go.mod, Cargo.lock, Gemfile.lock) and any Dockerfiles for the affected packages, including transitive dependencies.
2. If an affected version is in use, upgrade it to the fixed version for its release line with the project's package manager, so the lockfile is regenerated. Prefer the smallest upgrade that fixes it.
3. If there is no fix, or the upgrade would break the build, do not guess: explain the risk and the safest workaround instead.
4. Run the tests and summarise what changed and why.
5. If nothing in the project is affected, say so and change nothing.

Reference: https://insights.sbomify.com/CVE-2026-45190/ (Markdown: https://insights.sbomify.com/CVE-2026-45190/index.md)
```

## Sources

- CVE record: https://www.cve.org/CVERecord?id=CVE-2026-45190
- NVD: https://nvd.nist.gov/vuln/detail/CVE-2026-45190
- OSV: https://osv.dev/vulnerability/CVE-2026-45190

---
From sbomify Insights: https://insights.sbomify.com/CVE-2026-45190/
Summaries are generated and may contain mistakes; the official description above is the record.