CVE-2021-47156

MEDIUMNVD 6.56.5—

6.5

The Net::IPAddress::Util module before 5.000 for Perl does not properly consider extraneous zero characters in an IP address string, which (in some situations) allows attackers to bypass access control that is based on IP addresses.

CVSS v3: 6.5
EG Score: 6.5(medium)
EPSS: 31.2%
KEV: Not listed

Published

March 18, 2024

Last Modified

April 15, 2026

References (6)

cve@mitrehttps://blog.urth.org/2021/03/29/security-issues-in-perl-ip-address-distros/
cve@mitrehttps://metacpan.org/release/Net-IPAddress-Util
cve@mitrehttps://metacpan.org/release/PWBENNETT/Net-IPAddress-Util-5.000/changes
af854a3a-2127-422b-91ae-364da2661108https://blog.urth.org/2021/03/29/security-issues-in-perl-ip-address-distros/
af854a3a-2127-422b-91ae-364da2661108https://metacpan.org/release/Net-IPAddress-Util
af854a3a-2127-422b-91ae-364da2661108https://metacpan.org/release/PWBENNETT/Net-IPAddress-Util-5.000/changes

Weakness Classification(1)

MITRE Common Weakness Enumeration — the root-cause categories this CVE belongs to.

CWE-1287

Data Freshness Timeline

(refreshed 20× in last 7d / 20× in last 30d)

Every time one of our enrichment pipelines (NVD, MITRE cvelistV5, EPSS, CISA KEV, GHSA, OSV, vendor advisories) ran against this CVE. Most recent first.

2026-05-27 13:39 UTCepss_batch
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2026-05-26 13:43 UTCepss_batch
2026-05-26 13:42 UTCepss_batch
2026-05-26 07:17 UTCepss_batch
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2026-05-22 21:16 UTCepss_batch
2026-05-22 04:13 UTCEG score recompute
2026-05-22 04:13 UTCGHSA enrichment
2026-05-21 22:41 UTCepss_batch
2026-05-21 22:41 UTCepss_batch
2026-05-20 22:37 UTCepss_batch
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2026-05-20 22:37 UTCepss_batch

Frequently asked(5)

What is CVE-2021-47156?

CVE-2021-47156 is a medium vulnerability published on March 18, 2024. The Net::IPAddress::Util module before 5.000 for Perl does not properly consider extraneous zero characters in an IP address string, which (in some situations) allows attackers to bypass access control that is based on IP addresses.

When was CVE-2021-47156 disclosed?

CVE-2021-47156 was first published in the National Vulnerability Database on March 18, 2024, with the most recent update on April 15, 2026. EchelonGraph re-ingests CVE updates from NVD on a 2-hour cycle, so this page reflects the latest published state.

Is CVE-2021-47156 actively exploited?

CVE-2021-47156 is not currently on CISA's Known Exploited Vulnerabilities catalog. FIRST EPSS estimates a 31.2% percentile likelihood of exploitation in the next 30 days — higher percentiles indicate greater predicted risk.

What is the CVSS score of CVE-2021-47156?

CVE-2021-47156 has a CVSS v3 base score of 6.5 (NVD).

How do I remediate CVE-2021-47156?

Patch to the fixed version published by the affected vendor. Where vendor advisories exist for CVE-2021-47156, EchelonGraph cross-links them in the Vendor Advisories panel below — those typically contain the canonical remediation steps, fixed version numbers, and any vendor-specific mitigations.

Dependency Blast Radius

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CVE-2021-47156

📅 Published

🔄 Last Modified

🔗 References (6)