# CVE-2026-49941: Net::CIDR::Set versions through 0.20 for Perl did not validate IP addresses

> An attacker can cause a denial of service in Perl applications using Net::CIDR::Set by providing malformed IP addresses that trigger indefinite recursion.

- **Severity:** High 7.5 (`CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:H`)
- **Exploited in the wild:** Not known
- **Login needed:** Not needed
- **Attackable:** Over the internet
- **Victim action needed:** Not needed
- **Fix available:** Yes
- **Published:** 4 Jun 2026
- **Updated:** 4 Jun 2026
- **Also known as:** DEBIAN-CVE-2026-49941, GHSA-wvxw-q92g-9ghf, UBUNTU-CVE-2026-49941

## What is CVE-2026-49941?

CVE-2026-49941 is a high-severity denial of service vulnerability in RRWO Net::CIDR::Set, published on 4 Jun 2026. An attacker can exploit it over the internet without logging in, with no action from the victim.

### Official description

Net::CIDR::Set versions through 0.20 for Perl did not validate IP addresses.

The add method called the _encode method to parse addresses. If the addresses did not look like netmasks or network ranges, then they were assumed to single IP addresses and passed back to itself as a 32-bit or 128-bit netmask.

If the argument was not a well-formed IP address, then this would lead to indefinite recursion.

An attacker could use this to cause a denial of service.

Weakness: CWE-674 (Uncontrolled Recursion), CWE-1287 (Improper Validation of Specified Type of Input)

## Which versions are affected by CVE-2026-49941?

It affects 1 product.


Products: Rrwo Net\.

## How do I fix CVE-2026-49941?

Upgrade to a fixed version.

## Is CVE-2026-49941 being exploited?

There is no known exploitation of CVE-2026-49941 in the wild and no public exploit code.

## Other vulnerabilities in RRWO Net::CIDR::Set

- [CVE-2026-49942](https://insights.sbomify.com/CVE-2026-49942/): Net::CIDR::Set versions through 0.20 for Perl did not validate network masks (high 7.3)
- [CVE-2026-49940](https://insights.sbomify.com/CVE-2026-49940/): Net::CIDR::Set versions through 0.20 for Perl accept non-ASCII IP addresses and netmasks (medium 6.5)

## Fix prompt for AI coding agents

```text
Check this codebase for CVE-2026-49941 and fix it if it is affected.

What it is: CVE-2026-49941 is a high-severity denial of service vulnerability in RRWO Net::CIDR::Set, published on 4 Jun 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-2026-49941 in the wild and no public exploit code.

Affected product: RRWO Net::CIDR::Set. 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-2026-49941/ (Markdown: https://insights.sbomify.com/CVE-2026-49941/index.md)
```

## Sources

- CVE record: https://www.cve.org/CVERecord?id=CVE-2026-49941
- NVD: https://nvd.nist.gov/vuln/detail/CVE-2026-49941
- OSV: https://osv.dev/vulnerability/CVE-2026-49941

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From sbomify Insights: https://insights.sbomify.com/CVE-2026-49941/
Summaries are generated and may contain mistakes; the official description above is the record.