Net\Application · Rrwo

CVE-2026-49941

HIGH · 7.5 CVSS v3.1 Published 2026-06-04
Fix available
A fix is available. Upgrade to 0.21 or later.
See remediation →
84/100
Remediation priority · High
Remotely reachable No privileges Zero-click

Official description Straight from the sourceThe vendor's or NVD's own wording, published unedited. Authoritative, but often terse — it says what broke, rarely what to do.

NVD · unedited
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.

Technical summary Written by usOur analysis, written from the advisory, the CVSS vector and the affected-version data. It adds context the advisory leaves out, and never invents facts that are not in the source.

dbcve analysis · high confidence

The Net::CIDR::Set Perl module (versions through 0.20) fails to validate IP addresses in the add method. When addresses don't match netmask or network range format, they're treated as single IPs and passed as 32/128-bit netmasks back to the add method, causing infinite recursion with malformed input leading to denial of service.

MitigationUpdate to a patched version of Net::CIDR::Set when available; until then, implement input validation sanitization before calling add() to reject malformed IP strings.

Verify against the referenced sources before acting — the references below are authoritative for this CVE, this summary is not.

Affected products & versions What the vendor confirmedThe version ranges the vendor confirmed as vulnerable. If your version sits inside a range here, treat yourself as exposed until you have upgraded.

NVD · CPE data
Net\Application
Affected:< 0.21

CVSS breakdown How the score is builtThe industry scoring standard. It rates how the flaw is reached, what it takes to exploit, and what an attacker gains — the score is derived from those, not the other way round.

From the vector
Attack vector
Network
Complexity
Low
Privileges
None
User interaction
None
Scope
Unchanged
Confidentiality
None
Integrity
None
Availability
High

CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:H

Am I affected? How to checkSteps we derive from the advisory and the affected-version data, so you can decide whether this CVE reaches your setup. They are a guide, not a scan — your own configuration is the authority.

dbcve checks

Work through these to decide whether this CVE applies to you.

  1. Check if Net::CIDR::Set is installed
    Run `perl -MNet::CIDR::Set -e 'print "Installed\n"'` to verify the module exists on the system
    Affected if The module is not installed or the command fails
  2. Determine the installed version of Net::CIDR::Set
    Run `perl -MNet::CIDR::Set -e 'print $Net::CIDR::Set::VERSION'` to obtain the version number
    Affected if The version is 0.20 or lower (any version through 0.20 is affected)
  3. Check for Perl scripts using the add() method
    Search source code for patterns like `->add(` or `add(` where Net::CIDR::Set objects are used, such as `grep -r '->add(' /path/to/code`
    Affected if Code calls the add() method on Net::CIDR::Set objects
  4. Inspect input sources to add() method
    Review code paths where data flows into add() calls; check if input comes from user input, external files, APIs, or network sources without prior validation
    Affected if Untrusted or unsanitized input can reach the add() method, enabling malicious crafted input to trigger infinite recursion

You are affected if Net::CIDR::Set version 0.20 or lower is installed AND your code uses the add() method with input that could be malformed or from untrusted sources.

Generated from the published advisory. Verify against your own configuration.

Check your environment

Paste your version and any relevant configuration and it will be compared against the affected criteria above. Do not include secrets or credentials.

AI-assisted, checked against the advisory. Informational, not a guarantee.

Remediation Closing itWhat it takes to close this. Where a vendor fix exists we point at it; where none exists we say so plainly, and can build one. Effort estimates are scoped from the advisory, not from your codebase.

dbcve · scoped
Upgrade available Upgrade to 0.21 or later
Fixed in 0.21
Interim mitigation

Update to a patched version of Net::CIDR::Set when available; until then, implement input validation sanitization before calling add() to reject malformed IP strings.

Recommended fix High confidence

Net::CIDR::Set version 0.21

  1. Upgrade Net::CIDR::Set to version 0.21 or later using your Perl module management tool (e.g., 'cpan Net::CIDR::Set' or 'cpanm Net::CIDR::Set')
  2. Verify the installed version using 'perl -MNet::CIDR::Set -e "print $Net::CIDR::Set::VERSION"'
  3. Ensure the version is 0.21 or higher
Caveat None documented in the provided references

Generated from the published advisory — verify against the referenced sources before acting.

Fix this in Net\ Scoped from the published advisory
  • Consultation3.0 h
  • Implementation6.0 h
  • Testing4.0 h
  • Review / QA2.0 h
15.0 hours of engineering $2,640
Get the upgrade done

An estimate, not a bill — we confirm scope with you before any work starts. Need it this week? Rush from $4,224.

Scan for this in your stack

Free · runs locally
dbcve dependency scanner

Check whether your project pulls in CVE-2026-49941 — or any other known-vulnerable package — straight from your lock files. Free and open source; it runs locally and uploads nothing.

References Go to the primary sourcePrimary sources — vendor advisories, patches and trackers. Where our summary and a reference disagree, the reference wins.

Primary sources

Practitioner notes

Contributed

Peer-ranked notes from engineers who’ve handled CVE-2026-49941 in production — separate from our analysis above.

No notes yet

Be the first to add a field note for this CVE — a mitigation you’ve verified, a version caveat, or a link to a working fix. Sign in above to contribute.

What this is

A place for practitioners to share what actually worked: a mitigation you’ve tested, a configuration change, a version- or environment-specific caveat, or a link to a verified patch. The most useful notes rise to the top as peers upvote them, so the signal stays high.

What belongs here
  • Verified mitigations, workarounds, and config changes
  • Version or environment caveats, and links to real fixes
  • No weaponised exploit code, or anything meant to cause harm
  • No spam, self-promotion, credentials, or personal data