CVE-2021-23901 | An XML external entity (XXE) injection vulnerability exists in the Nutch DmozParser

An XML external entity (XXE) injection vulnerability was discovered in the Nutch DmozParser and is known to affect Nutch versions < 1.18. XML external entity injection (also known as XXE) is a web security vulnerability that allows an attacker to interfere with an application's processing of XML data. It often allows an attacker to view files on the application server filesystem, and to interact with any back-end or external systems that the application itself can access. This issue is fixed in Apache Nutch 1.18.

Published: 2021-01-25 Last update: 2026-06-16 Assigner: [email protected] Source: [email protected]
NVD Status：Modified，CVE State: published
View at NVD, CVE.org, EUVD

CVE-2021-23901 is rated High Risk (71.2/100): CVSS Critical severity, with medium exploitation likelihood (EPSS 4.36%). EPSS rose +3.29% over the last day, indicating growing attacker interest. High exploitation likelihood—assess exposure and prioritize remediation.

Risk is dynamic; we continuously reassess and refresh what is shown on this page as upstream context changes.

Exploit prediction scoring system (EPSS) score for CVE-2021-23901

EPSS lead: Daily EPSS estimates relative likelihood of exploitation; percentile ranks this CVE among scored vulnerabilities (higher = more severe relative rank).

# Date Old EPSS score New EPSS score Delta (New - Old)
1 2026-06-15 1.07% 4.36% +3.29%
2 2025-11-21 2.05% 1.07% -0.98%
3 2025-11-18 — 2.05% —

Full EPSS history (19 records total)

Common vulnerability scoring system (CVSS) metrics for CVE-2021-23901

CVSS metrics for this CVE.

Base score Version Severity Vector Exploitability Impact Score source
9.1 3.1 CRITICAL
CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:H/A:N Click to expand
Attack vector (AV:N)
Could be attacked over the internet or any normal routed network—not just someone sitting at the machine.
Attack complexity (AC:L)
Once they can reach the bug, pulling it off is straightforward—no weird race conditions or rare setup.
Privileges required (PR:N)
No account or special rights needed—anonymous or random user is enough.
User interaction (UI:N)
Nobody has to click “OK” or open a trap file; it can work without a victim helping.
Scope (S:U)
Damage stays in the same “trust bubble” as the broken component—no big spill into unrelated systems.
Confidentiality (C:H)
Serious risk that confidential data gets exposed in a big way.
Integrity (I:H)
They could widely tamper with or forge data—trust in the data is badly hurt.
Availability (A:N)
Service keeps running; no real outage angle.
 3.9 5.2 [email protected]
6.4 2.0 MEDIUM
AV:N/AC:L/Au:N/C:P/I:P/A:N Click to expand
Access vector (AV:N)
Can be exploited remotely over network reachability.
Access complexity (AC:L)
Exploitation conditions are straightforward and predictable.
Authentication (AU:N)
No authentication is required.
Confidentiality impact (C:P)
Partial confidentiality impact.
Integrity impact (I:P)
Partial integrity impact.
Availability impact (A:N)
No availability impact.
 10.0 4.9 [email protected]

Weakness enumeration for CVE-2021-23901

GitHub Security Advisory for CVE-2021-23901

GHSA-fxhp-wrw9-3r97 · Severity: critical · Ecosystem: maven — XML external entity (XXE) injection in Apache Nutch

OS Trackers for CVE-2021-23901

vendor priority summary link
suse critical CVE-2021-23901 severity critical: SUSE including 275 source package names (amazon/suse-sles-15-sp1-chost-byos-v20210304-hvm-ssd-x86_64, amazon/suse-sles-15-sp1-chost-byos-v20220127-hvm-ssd-x86_64, …), 275 product×package rows across 3 product lines (SUSE Manager Server Module 4.0, SUSE Manager Server Module 4.1, chost): Known Affected 231, Fixed 44. https://www.suse.com/security/cve/CVE-2021-23901/

Affected software / configurations for CVE-2021-23901

Vendor Product Version Raw CPE
apache nutch < 1.18 cpe:2.3:a:apache:nutch:*:*:*:*:*:*:*:*
netapp snap_creator_framework — cpe:2.3:a:netapp:snap_creator_framework:-:*:*:*:*:*:*:*

References for CVE-2021-23901

cvelogic Threat Intelligence