How severe is CVE-2021-4305?

CVE-2021-4305 has a CVSS 3.x base score of 3.5, rated low severity. It is exploitable over an adjacent network with low attack complexity, requires low privileges and no user interaction. Impact on confidentiality is none, integrity none, and availability low.

Is CVE-2021-4305 being actively exploited?

It is not currently listed in CISA's KEV catalog. Its EPSS exploit-prediction score is 1% (57th percentile), an estimate of the probability of exploitation in the next 30 days.

What products are affected by CVE-2021-4305?

CVE-2021-4305 affects Bridgeline Robots-txt-guard. See the affected-products list for the exact vulnerable versions.

How do I fix CVE-2021-4305?

Review the linked vendor and NVD advisories for patched versions and mitigations, then upgrade or apply the recommended workaround.

When was CVE-2021-4305 published?

CVE-2021-4305 was published on 2023-01-05 and last updated on 2026-06-17.

CVE-2021-4305

CVE-2021-4305 is a low-severity vulnerability in Bridgeline Robots-txt-guard with a CVSS 3.x base score of 3.5. 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-1333.

Key facts

Severity: Low (CVSS 3.x base score 3.5)
CVSS v2: 2.3
EPSS exploit prediction: 1% (57th percentile)
Actively exploited: Not listed in CISA KEV
Weakness: CWE-1333
Affected product: Bridgeline Robots-txt-guard
Published: 2023-01-05
Last modified: 2026-06-17

Description

A vulnerability was found in Woorank robots-txt-guard. It has been rated as problematic. Affected by this issue is the function makePathPattern of the file lib/patterns.js. The manipulation of the argument pattern leads to inefficient regular expression complexity. The exploit has been disclosed to the public and may be used. The name of the patch is c03827cd2f9933619c23894ce7c98401ea824020. It is recommended to apply a patch to fix this issue. The identifier of this vulnerability is VDB-217448.

Frequently asked questions

What is CVE-2021-4305?: A vulnerability was found in Woorank robots-txt-guard. It has been rated as problematic. Affected by this issue is the function makePathPattern of the file lib/patterns.js. The manipulation of the argument pattern leads to inefficient regular expression complexity. The exploit has been disclosed to the public and may be used. The name of the patch is c03827cd2f9933619c23894ce7c98401ea824020. It is recommended to apply a patch to fix this issue. The identifier of this vulnerability is VDB-217448.
How severe is CVE-2021-4305?: CVE-2021-4305 has a CVSS 3.x base score of 3.5, rated low severity. It is exploitable over an adjacent network with low attack complexity, requires low privileges and no user interaction. Impact on confidentiality is none, integrity none, and availability low.
Is CVE-2021-4305 being actively exploited?: It is not currently listed in CISA's KEV catalog. Its EPSS exploit-prediction score is 1% (57th percentile), an estimate of the probability of exploitation in the next 30 days.
What products are affected by CVE-2021-4305?: CVE-2021-4305 affects Bridgeline Robots-txt-guard. See the affected-products list for the exact vulnerable versions.
How do I fix CVE-2021-4305?: Review the linked vendor and NVD advisories for patched versions and mitigations, then upgrade or apply the recommended workaround.
When was CVE-2021-4305 published?: CVE-2021-4305 was published on 2023-01-05 and last updated on 2026-06-17.

References

Affected products (1)

cpe:2.3:a:bridgeline:robots-txt-guard:*:*:*:*:*:*:*:*

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