CVE-2021-29943 | Apache Solr Unprivileged users may be able to perform unauthorized read/write to collections

When using ConfigurableInternodeAuthHadoopPlugin for authentication, Apache Solr versions prior to 8.8.2 would forward/proxy distributed requests using server credentials instead of original client credentials. This would result in incorrect authorization resolution on the receiving hosts.

Published: 2021-04-13 Last update: 2024-11-21 Assigner: [email protected] Source: [email protected]
NVD Status：Modified，CVE State: published
View at NVD, CVE.org, EUVD

CVE-2021-29943 is rated High Risk (67.9/100): CVSS Critical severity, with high exploitation likelihood (EPSS 5.26%, 91th percentile). EPSS ranks this CVE among the most likely to be exploited in the near term. 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-2021-29943

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 5.80% 5.26% -0.54%
2 2026-04-29 7.67% 5.80% -1.87%
3 2025-11-21 — 7.67% —

Full EPSS history (19 records total)

Common vulnerability scoring system (CVSS) metrics for CVE-2021-29943

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-2021-29943

GitHub Security Advisory for CVE-2021-29943

GHSA-vf7p-j8x6-xvwp · Severity: critical · Ecosystem: maven — Incorrect Authorization in Apache Solr

OS Trackers for CVE-2021-29943

vendor priority summary link
debian unimportant CVE-2021-29943 unimportant priority: Debian including 1 source packages (lucene-solr), 5 status rows across 5 suites (bookworm, bullseye, forky, sid, trixie): resolved 5. https://security-tracker.debian.org/tracker/CVE-2021-29943
redhat high — https://access.redhat.com/security/cve/CVE-2021-29943
ubuntu medium CVE-2021-29943 medium priority: Ubuntu including 1 source packages (lucene-solr), 14 status rows across 14 suites (bionic, focal, groovy, jammy, kinetic, lunar, mantic, noble, oracular, plucky, questing, trusty, upstream, xenial): not-affected 13, needed 1. https://ubuntu.com/security/CVE-2021-29943

Affected software / configurations for CVE-2021-29943

Vendor Product Version Raw CPE
apache solr < 8.8.2 cpe:2.3:a:apache:solr:*:*:*:*:*:*:*:*

References for CVE-2021-29943

cvelogic Threat Intelligence