CVE-2021-29424
Status: ModifiedHigh (7.5)—
The Net::Netmask module before 2.0000 for Perl does not properly consider extraneous zero characters at the beginning of an IP address string, which (in some situations) allows attackers to bypass access control that is based on IP addresses.
CVSS
- Version: 3.1
- Vector: CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:H/A:N
- Base score: 7.5
Exploitation probability (EPSS)
- Probability of exploitation in the next 30 days: 1.80%
- Percentile among all scored CVEs: 78
- Score date: 10/12/2026
EPSS (Exploit Prediction Scoring System, FIRST) estimates how likely a vulnerability is to be exploited in the wild within 30 days. It complements CVSS (impact) and CISA KEV (confirmed exploitation).
Affected technologies (2)
CWEs
- CWE-704
References
- https://blog.urth.org/2021/03/29/security-issues-in-perl-ip-address-distros/
- https://lists.fedoraproject.org/archives/list/package-announce%40lists.fedoraproject.org/message/CBJVLXJSWN6DKSF5ADUEERI6M23R3GGP/
- https://lists.fedoraproject.org/archives/list/package-announce%40lists.fedoraproject.org/message/JF4CYIZELC3NISB3RMV4OCI4GYBC557B/
- https://lists.fedoraproject.org/archives/list/package-announce%40lists.fedoraproject.org/message/Y7JIPQAY5OZ5D3DA7INQILU7SGHTHMWB/
- https://metacpan.org/changes/distribution/Net-Netmask#L11-22
- https://security.netapp.com/advisory/ntap-20210604-0007/
- https://blog.urth.org/2021/03/29/security-issues-in-perl-ip-address-distros/
- https://lists.fedoraproject.org/archives/list/package-announce%40lists.fedoraproject.org/message/CBJVLXJSWN6DKSF5ADUEERI6M23R3GGP/
- https://lists.fedoraproject.org/archives/list/package-announce%40lists.fedoraproject.org/message/JF4CYIZELC3NISB3RMV4OCI4GYBC557B/
- https://lists.fedoraproject.org/archives/list/package-announce%40lists.fedoraproject.org/message/Y7JIPQAY5OZ5D3DA7INQILU7SGHTHMWB/
- https://metacpan.org/changes/distribution/Net-Netmask#L11-22
- https://security.netapp.com/advisory/ntap-20210604-0007/
Raw JSON (NVD)
Show
{
"id": "CVE-2021-29424",
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"authentication": "NONE",
"integrityImpact": "PARTIAL",
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},
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"value": "El módulo Net::Netmask versiones anteriores a 2.0000 para Perl no considera apropiadamente los caracteres cero extraños al comienzo de una cadena de dirección IP, lo que (en algunas situaciones) permite a atacantes omitir el control de acceso basado en direcciones IP"
}
],
"lastModified": "2026-06-17T03:47:36.420",
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