What is the CVSS score of CVE-2021-36126?

CVE-2021-36126 has a CVSS 3.1 base score of 9.8 (Critical). CVSS vector: CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:H/A:H. EPSS exploitation probability: 1.2%.

Is there a public PoC exploit available for CVE-2021-36126?

Yes, a public proof-of-concept exploit is available for CVE-2021-36126. Prioritise patching immediately. EPSS: 1.2%.

Is there a patch available for CVE-2021-36126?

Yes, a patch is available for CVE-2021-36126. Update the affected software to the latest version immediately.

Mediawiki CVE-2021-36126

CRITICAL

2021-07-02 cve@mitre.org

Information Disclosure Mediawiki

9.8

CVSS 3.1 · NVD

View

Vulnerability Assessment

Impact	CVSS score of 9.8 (CRITICAL). Attack characteristics: network attack vector, low complexity, no privileges required, no user interaction not required. Public proof-of-concept exploit code is available.
Exploit ScenarioDerived	This vulnerability can be exploited remotely over the network. Successful exploitation could compromise the critical-severity affected system.

Act Now Prioritize within 24-48h. Why: CRITICAL severity + public POC available.

Patch available 1.2% exploitation probability (EPSS)

Get an e-mail when this CVE is exploited, patched or re-scored. Free account.

Alert me

AnalysisAI

An issue was discovered in the AbuseFilter extension in MediaWiki through 1.36. Rated critical severity (CVSS 9.8), this vulnerability is remotely exploitable, no authentication required, low attack complexity. Public exploit code available.

RemediationAI

A vendor patch is available. Apply the latest security update as soon as possible. Apply vendor patches when available. Implement network segmentation and monitoring as interim mitigations.

Affects your stack

Find out whether the stacks and servers you run are on an affected version.

Checking this CVE against your own stacks and servers is part of the Basic plan and up.

Technical ContextAI · show details

An issue was discovered in the AbuseFilter extension in MediaWiki through 1.36. If the MediaWiki:Abusefilter-blocker message is invalid within the content language, the filter user falls back to the English version, but that English version could also be invalid on a wiki. This would result in a fatal error, and potentially fail to block or restrict a potentially nefarious user. Affected products include: Mediawiki. Version information: through 1.36..

Know when Mediawiki gets its next vulnerability

Watch products and get an email when something new is published
Check this CVE against your own stack and servers
Exploit and PoC references, threat intelligence from 22 sources

Continue with Google Continue with GitHub

No credit card · 7-day full trial

Severity by source

NVD PRIMARY 9.8 CRITICAL

AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:H/A:H

Primary rating from NVD · only source for this CVE.

CVSS VectorNVD

Attack Vector

Network

Attack Complexity

Low

Privileges Required

None

User Interaction

None

Scope

Unchanged

Confidentiality

High

Integrity

High

Availability

High

DescriptionNVD

Threat Intelligence Overview

EPSS Score

1.2%

Top 35% exploitable

Exploit

POC

Public exploit code exists

Data Quality

2 sources

Confidence: Low

NVD

CVE.org

EPSS

How this decision was reached

The engine reads each signal below and applies a fixed list of rules from top to bottom. The first rule that matches sets the recommended action – like a statement, every line is shown.

SignalValue

Severity CRITICAL

CISA KEV No

Public POC Yes

EPSS 1.2%

Patch available Yes

Active threat No

Deciding rule

CRITICAL severity + public POC available

What every action level means

Emergency Immediate action required. Criteria: CRITICAL + in CISA KEV (actively exploited) without patch, OR CRITICAL + EPSS > 30% without patch, OR CRITICAL + active threat signals without patch.

Act Now Prioritize within 24-48h. Criteria: in KEV with patch available, OR CRITICAL + public POC, OR HIGH + EPSS > 10%, OR CRITICAL + active threat, OR any CRITICAL severity.

This Week Schedule remediation this week. Criteria: HIGH severity (CVSS 7.0-8.9). Patch within normal change window.

This Month Plan within 30 days. Criteria: MEDIUM severity (CVSS 4.0-6.9), lower exploitation probability. Include in regular patch cycle.

Monitor Track and reassess. Criteria: LOW severity (CVSS 0.1-3.9), minimal exploitation risk. No immediate action needed.

SSVC AssessmentENISA

SSVC Decision· derived

Scheduled

Exploitation· derived

Poc

System Exposure· derived

Open

Automatable· derived

Yes

Human Impact· derived

Medium

Priority Score

Low Medium High Critical

KEV: 0

EPSS: +1

CVSS: +49

PoC: +20

Weaponized: 0

Threat intel: 0

Gov advisory: 0

Attack Technique

Information Disclosure MEDIUM

Information disclosure occurs when an application unintentionally exposes sensitive data that aids attackers in reconnaissance or directly compromises security.

Affected Products (CPE)NVD

cpe:2.3:a:mediawiki:mediawiki:*:*:*:*:*:*:*:*

More in Mediawiki

View all

CVE-2014-1610 MEDIUM This Month POC

6.0 Jan 30

MediaWiki 1.22.x before 1.22.2, 1.21.x before 1.21.5, and 1.19.x before 1.19.11, when DjVu or PDF file upload support is

CVE-2015-8009 CRITICAL Act Now POC

9.8 Jul 25

The MWOAuthDataStore::lookup_token function in Extension:OAuth for MediaWiki 1.25.x before 1.25.3, 1.24.x before 1.24.4,

CVE-2023-37303 CRITICAL Act Now POC

9.8 Jun 30

An issue was discovered in the CheckUser extension for MediaWiki through 1.39.3. Rated critical severity (CVSS 9.8), thi

CVE-2022-29906 CRITICAL Act Now POC

9.8 Apr 29

The admin API module in the QuizGame extension for MediaWiki through 1.37.2 (before 665e33a68f6fa1167df99c0aa18ed0157cdf

CVE-2022-29904 CRITICAL Act Now POC

9.8 Apr 29

The SemanticDrilldown extension for MediaWiki through 1.37.2 (before e688bdba6434591b5dff689a45e4d53459954773) allows SQ

CVE-2022-28206 CRITICAL Act Now POC

9.8 Mar 30

An issue was discovered in MediaWiki through 1.37.1. Rated critical severity (CVSS 9.8), this vulnerability is remotely

CVE-2022-28205 CRITICAL Act Now POC

9.8 Mar 30

An issue was discovered in MediaWiki through 1.37.1. Rated critical severity (CVSS 9.8), this vulnerability is remotely

CVE-2021-36128 CRITICAL Act Now POC

9.8 Jul 02

An issue was discovered in the CentralAuth extension in MediaWiki through 1.36. Rated critical severity (CVSS 9.8), this

CVE-2017-8809 CRITICAL Act Now

9.8 Nov 15

api.php in MediaWiki before 1.27.4, 1.28.x before 1.28.3, and 1.29.x before 1.29.2 has a Reflected File Download vulnera

CVE-2024-47849 HIGH This Week POC

8.8 Oct 05

Improper Neutralization of Special Elements used in an SQL Command ('SQL Injection') vulnerability in The Wikimedia Foun

CVE-2021-36132 HIGH This Week POC

8.8 Jul 02

An issue was discovered in the FileImporter extension in MediaWiki through 1.36. Rated high severity (CVSS 8.8), this vu

CVE-2025-61682 HIGH This Week POC

8.6 Sep 18

Stored cross-site scripting in Semantic MediaWiki 3.1.0 through 6.x lets users with the MediaWiki 'edit' right inject ar

Same technique Information Disclosure

View all

CVE-2019-2725 CRITICAL POC

9.8

CVE-2021-34523 CRITICAL POC

9.0

CVE-2013-2251 CRITICAL POC

9.8

CVE-2017-5638 CRITICAL POC

9.8

CVE-2025-24813 CRITICAL POC

9.8

CVE-2025-68613 HIGH POC

8.8

CVE-2015-1701 HIGH POC

7.8

CVE-2017-0147 HIGH POC

7.5

References

Advisories & patches

PATCH https://gerrit.wikimedia.org/r/q/I9e9f44b7663e810de70fb9ac7f6760f83dd4895b

Search Externally

GitHub PoC

Exploit-DB PacketStorm Snyk Rapid7 Nuclei Templates Trickest PoC

Back