How severe is CVE-2021-47155?

CVE-2021-47155 has a CVSS 3.x base score of 9.1, rated critical severity. It is exploitable over network with low attack complexity, requires no privileges and no user interaction. Impact on confidentiality is high, integrity high, and availability none.

Is CVE-2021-47155 being actively exploited?

It is not currently listed in CISA's KEV catalog. Its EPSS exploit-prediction score is 1% (40th percentile), an estimate of the probability of exploitation in the next 30 days.

How do I fix CVE-2021-47155?

Review the linked vendor and NVD advisories for patched versions and mitigations, then upgrade or apply the recommended workaround. Given its critical severity, prioritise patching exposed systems.

Does CVE-2021-47155 have an EU (EUVD) identifier?

Yes. CVE-2021-47155 is tracked in the ENISA EU Vulnerability Database (EUVD) as EUVD-2021-33803.

When was CVE-2021-47155 published?

CVE-2021-47155 was published on 2024-03-18 and last updated on 2026-06-17.

CVE-2021-47155

CVE-2021-47155 is a critical-severity vulnerability with a CVSS 3.x base score of 9.1. It is not currently listed as actively exploited by CISA, and its EPSS exploit-prediction score is low. The underlying weakness is classified as CWE-284.

Key facts

Severity: Critical (CVSS 3.x base score 9.1)
EPSS exploit prediction: 1% (40th percentile)
Actively exploited: Not listed in CISA KEV
EU (EUVD) id: EUVD-2021-33803
Weakness: CWE-284
Published: 2024-03-18
Last modified: 2026-06-17

Description

The Net::IPV4Addr module 0.10 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.

Frequently asked questions

What is CVE-2021-47155?: The Net::IPV4Addr module 0.10 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.
How severe is CVE-2021-47155?: CVE-2021-47155 has a CVSS 3.x base score of 9.1, rated critical severity. It is exploitable over network with low attack complexity, requires no privileges and no user interaction. Impact on confidentiality is high, integrity high, and availability none.
Is CVE-2021-47155 being actively exploited?: It is not currently listed in CISA's KEV catalog. Its EPSS exploit-prediction score is 1% (40th percentile), an estimate of the probability of exploitation in the next 30 days.
How do I fix CVE-2021-47155?: Review the linked vendor and NVD advisories for patched versions and mitigations, then upgrade or apply the recommended workaround. Given its critical severity, prioritise patching exposed systems.
Does CVE-2021-47155 have an EU (EUVD) identifier?: Yes. CVE-2021-47155 is tracked in the ENISA EU Vulnerability Database (EUVD) as EUVD-2021-33803.
When was CVE-2021-47155 published?: CVE-2021-47155 was published on 2024-03-18 and last updated on 2026-06-17.

References

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