STIGTSP Net::CIDR::Lite up to 0.22 on Perl _pack_ipv6 improper validation of syntactic correctness of input

CVSS Meta Temp Score
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CTI Interest Score
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7.0$0-$5k0.00

Summaryinfo

A vulnerability classified as critical has been found in STIGTSP Net::CIDR::Lite up to 0.22 on Perl. The impacted element is the function _pack_ipv6. The manipulation leads to improper validation of syntactic correctness of input. This vulnerability is uniquely identified as CVE-2026-40198. The attack is possible to be carried out remotely. No exploit exists. It is recommended to upgrade the affected component.

Detailsinfo

A vulnerability was found in STIGTSP Net::CIDR::Lite up to 0.22 on Perl. It has been rated as critical. This issue affects the function _pack_ipv6. The manipulation with an unknown input leads to a improper validation of syntactic correctness of input vulnerability. Using CWE to declare the problem leads to CWE-1286. The product receives input that is expected to be well-formed - i.e., to comply with a certain syntax - but it does not validate or incorrectly validates that the input complies with the syntax. Impacted is confidentiality, integrity, and availability. The summary by CVE is:

Net::CIDR::Lite versions before 0.23 for Perl does not validate IPv6 group count, which may allow IP ACL bypass. _pack_ipv6() does not check that uncompressed IPv6 addresses (without ::) have exactly 8 hex groups. Inputs like "abcd", "1:2:3", or "1:2:3:4:5:6:7" are accepted and produce packed values of wrong length (3, 7, or 15 bytes instead of 17). The packed values are used internally for mask and comparison operations. find() and bin_find() use Perl string comparison (lt/gt) on these values, and comparing strings of different lengths gives wrong results. This can cause find() to incorrectly report an address as inside or outside a range. Example: my $cidr = Net::CIDR::Lite->new("::/8"); $cidr->find("1:2:3"); # invalid input, incorrectly returns true This is the same class of input validation issue as CVE-2021-47154 (IPv4 leading zeros) previously fixed in this module. See also CVE-2026-40199, a related issue in the same function affecting IPv4 mapped IPv6 addresses.

The advisory is shared at github.com. The identification of this vulnerability is CVE-2026-40198 since 04/10/2026. The exploitation is known to be easy. The attack may be initiated remotely. No form of authentication is needed for a successful exploitation. Technical details are known, but no exploit is available.

The vulnerability scanner Nessus provides a plugin with the ID 306023 (Linux Distros Unpatched Vulnerability : CVE-2026-40198), which helps to determine the existence of the flaw in a target environment.

Upgrading to version 0.23 eliminates this vulnerability. Applying the patch 25d65f85dbe4885959a10471725ec9d250a589c3 is able to eliminate this problem. The bugfix is ready for download at github.com. The best possible mitigation is suggested to be upgrading to the latest version.

The vulnerability is also documented in the databases at Tenable (306023) and EUVD (EUVD-2026-21609). If you want to get the best quality for vulnerability data then you always have to consider VulDB.

Productinfo

Vendor

Name

Version

License

CPE 2.3info

CPE 2.2info

CVSSv4info

VulDB Vector: 🔒
VulDB Reliability: 🔍

CVSSv3info

VulDB Meta Base Score: 7.3
VulDB Meta Temp Score: 7.0

VulDB Base Score: 7.3
VulDB Temp Score: 7.0
VulDB Vector: 🔒
VulDB Reliability: 🔍

CVSSv2info

AVACAuCIA
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VulDB Base Score: 🔒
VulDB Temp Score: 🔒
VulDB Reliability: 🔍

Exploitinginfo

Class: Improper validation of syntactic correctness of input
CWE: CWE-1286 / CWE-20
CAPEC: 🔒
ATT&CK: 🔒

Physical: No
Local: No
Remote: Yes

Availability: 🔒
Status: Not defined

EPSS Score: 🔒
EPSS Percentile: 🔒

Price Prediction: 🔍
Current Price Estimation: 🔒

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Nessus ID: 306023
Nessus Name: Linux Distros Unpatched Vulnerability : CVE-2026-40198

Threat Intelligenceinfo

Interest: 🔍
Active Actors: 🔍
Active APT Groups: 🔍

Countermeasuresinfo

Recommended: Upgrade
Status: 🔍

0-Day Time: 🔒

Upgrade: Net::CIDR::Lite 0.23
Patch: 25d65f85dbe4885959a10471725ec9d250a589c3

Timelineinfo

04/10/2026 CVE reserved
04/11/2026 +1 days Advisory disclosed
04/11/2026 +0 days VulDB entry created
04/12/2026 +0 days VulDB entry last update

Sourcesinfo

Advisory: 25d65f85dbe4885959a10471725ec9d250a589c3
Status: Confirmed

CVE: CVE-2026-40198 (🔒)
GCVE (CVE): GCVE-0-2026-40198
GCVE (VulDB): GCVE-100-356957
EUVD: 🔒

Entryinfo

Created: 04/11/2026 04:11
Updated: 04/12/2026 01:08
Changes: 04/11/2026 04:11 (58), 04/11/2026 22:16 (2), 04/12/2026 01:08 (1)
Complete: 🔍
Cache ID: 216::103

If you want to get the best quality for vulnerability data then you always have to consider VulDB.

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