How severe is CVE-2026-41871?

CVE-2026-41871 has a CVSS 3.x base score of 9.8, 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 high.

Is CVE-2026-41871 being actively exploited?

It is not currently listed in CISA's KEV catalog. Its EPSS exploit-prediction score is 1% (54th percentile), an estimate of the probability of exploitation in the next 30 days.

What products are affected by CVE-2026-41871?

CVE-2026-41871 affects Apache Nutch. See the affected-products list for the exact vulnerable versions.

How do I fix CVE-2026-41871?

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.

When was CVE-2026-41871 published?

CVE-2026-41871 was published on 2026-09-09 and last updated on 2026-09-10.

CVE-2026-41871

CVE-2026-41871 is a critical-severity vulnerability in Apache Nutch with a CVSS 3.x base score of 9.8. 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-470.

Key facts

Severity: Critical (CVSS 3.x base score 9.8)
EPSS exploit prediction: 1% (54th percentile)
Actively exploited: Not listed in CISA KEV
Weakness: CWE-470
Affected product: Apache Nutch
Published: 2026-09-09
Last modified: 2026-09-10

Description

Missing Authorization, Use of Externally-Controlled Input to Select Classes or Code ('Unsafe Reflection') vulnerability in Apache Nutch Server (Nutch REST API). This issue affects Apache Nutch: from 1.10 through 1.22. Users are recommended to upgrade to version 1.23, which removes the Nutch Server. If an upgrade is not possible, user must restrict access to instances running the Nutch Service to trusted users only. Please, also visit the Apache Nutch security advisories https://nutch.apache.org/documentation/security/ .

Frequently asked questions

What is CVE-2026-41871?: Missing Authorization, Use of Externally-Controlled Input to Select Classes or Code ('Unsafe Reflection') vulnerability in Apache Nutch Server (Nutch REST API). This issue affects Apache Nutch: from 1.10 through 1.22. Users are recommended to upgrade to version 1.23, which removes the Nutch Server. If an upgrade is not possible, user must restrict access to instances running the Nutch Service to trusted users only. Please, also visit the Apache Nutch security advisories https://nutch.apache.org/documentation/security/ .
How severe is CVE-2026-41871?: CVE-2026-41871 has a CVSS 3.x base score of 9.8, 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 high.
Is CVE-2026-41871 being actively exploited?: It is not currently listed in CISA's KEV catalog. Its EPSS exploit-prediction score is 1% (54th percentile), an estimate of the probability of exploitation in the next 30 days.
What products are affected by CVE-2026-41871?: CVE-2026-41871 affects Apache Nutch. See the affected-products list for the exact vulnerable versions.
How do I fix CVE-2026-41871?: 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.
When was CVE-2026-41871 published?: CVE-2026-41871 was published on 2026-09-09 and last updated on 2026-09-10.

References

Affected products (1)

cpe:2.3:a:apache:nutch:*:*:*:*:*:*:*:*

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