VulnerabilityPublished 5 May 2024Updated 4 Nov 2025

CVE-2024-34507: includes/CommentFormatter/CommentParser.php · Basic XSS

Source GCVE Database

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Authoritative record:CVE-2024-34507· High 7.4

Not known to be exploited · CVSS 7.4 High · fixed in 1.41.1 : patch mediawiki soon.

Data as of 3 Nov 2026, 17:20 UTC

CVSS 3.1 base score

7.4High

How severe the flaw is on the 0–10 CVSS scale.

Thin evidence

One scorer or none

CVSS scores by source
CISA-ADP	CVSS 3.1	7.4

Patch: Available – fixed in 1.41.1, 1.40.3, 1.39.7

CVSS:3.1/AV:N/AC:L/PR:N/UI:R/S:C/C:H/I:N/A:N

Attack Vector: Network
Attack Complexity: Low
Privileges Required: None
User Interaction: Required
Scope: Changed
Confidentiality: High
Integrity: None
Availability: None

Bold values are the worst case: easiest to exploit or largest impact.

Attack Vector: Network: The vulnerable component is bound to the network stack and the set of possible attackers extends beyond the other options listed, up to and including the entire Internet. Such a vulnerability is often termed 'remotely exploitable' and can be thought of as an attack being exploitable at the protocol level one or more network hops away (e.g., across one or more routers).
Attack Complexity: Low: Specialized access conditions or extenuating circumstances do not exist. An attacker can expect repeatable success against the vulnerable component.
Privileges Required: None: The attacker is unauthorized prior to attack, and therefore does not require any access to settings or files to carry out an attack.
User Interaction: Required: Successful exploitation of this vulnerability requires a user to take some action before the vulnerability can be exploited.
Scope: Changed: An exploited vulnerability can affect resources beyond the security scope managed by the security authority of the vulnerable component. In this case, the vulnerable component and the impacted component are different and managed by different security authorities.
Confidentiality: High: There is total loss of confidentiality, resulting in all resources within the impacted component being divulged to the attacker. Alternatively, access to only some restricted information is obtained, but the disclosed information presents a direct, serious impact.
Integrity: None: There is no loss of integrity within the impacted component.
Availability: None: There is no impact to availability within the impacted component.

Definitions: FIRST CVSS v3.1 specification.

Exploitation evidence

Disclosed: evidence found.
CVE published 5 May 2024
Detectable: no evidence on record.
No public nuclei template indexed
Weaponized: no evidence on record.
No public exploit code indexed in Metasploit or Exploit-DB
Exploited in the wildExploited: no evidence on record.
Not in CISA KEV and no source reports exploitation
Observed by OffSeq MirageSeen by Mirage: no evidence on record.
No attack traffic recorded by OffSeq Mirage sensors

A missing step is not evidence of safety. Sources: cve.org (opens in a new tab), the Metasploit, Exploit-DB and nuclei-templates index as of 3 Nov 2026.

Disclosed: The CVE record is public on cve.org. Its publication is t = 0.
Detectable: A public nuclei template can find exposed instances, for defenders and attackers alike.
Weaponized: A Metasploit exploit module or Exploit-DB entry exists (Metasploit scanner modules do not count), or CISA SSVC or the CVSS exploit maturity reports a public proof of concept.
Exploited in the wild: CISA KEV lists it, CISA SSVC rates exploitation active, or a source reports attacks.
Observed by OffSeq Mirage: OffSeq Mirage honeypot sensors recorded attack traffic for this CVE, or found exposed hosts without attack traffic.

Moments are spaced evenly, not to scale; a dashed line marks a gap of six months or more. Deltas count from t = 0. Sources that give only a date (CISA KEV, Exploit-DB, or a time of exactly 00:00Z) read “same day” rather than hours. Metasploit modules carry the flaw’s disclosure date, not their release date, and nuclei templates carry no date, so both appear above but not on the timeline.

ghsa-gwp7-78vh-mpmm

What to do

Upgrade mediawiki/mediawiki to 1.41.1, 1.40.3 or 1.39.7.

Affected software

Product	Affected	Fixed in
Packagistmediawiki/mediawiki`pkg:composer/mediawiki/mediawiki`Other threats	Affected <1.39.7 1.40.0 <1.40.3 1.41.0 <1.41.1	Fixed in 1.39.7 1.40.3 1.41.1

Check your own hosts for these packages with threat-finder (opens in a new tab), our free open-source scanner.

AI-suggested

A fix is available in MediaWiki versions 1.39.7, 1.40.3, and 1.41.1. Users should upgrade to these or later versions to remediate the vulnerability. Since this is a software vulnerability and not a cloud service, manual patching is required. No vendor advisory content was provided to indicate alternative mitigations or that no action is required.

Description

A cross-site scripting (XSS) vulnerability exists in MediaWiki versions before 1.39.7, 1.40.x before 1.40.3, and 1.41.x before 1.41.1 due to improper handling of the 0x1b character in the CommentParser.php component. This flaw can be triggered via the Special:RecentChanges page, potentially allowing an attacker to execute script code in the context of the affected site.

Impact

Successful exploitation allows an attacker to execute arbitrary scripts in the context of the affected MediaWiki site, potentially leading to information disclosure or session hijacking. The vulnerability impacts confidentiality but does not affect integrity or availability. No known exploits are reported in the wild at this time.

Summary

The vulnerability (CVE-2024-34507) affects the CommentParser.php file in MediaWiki prior to versions 1.39.7, 1.40.3, and 1.41.1. It arises from mishandling the 0x1b character, which leads to a cross-site scripting (XSS) condition. The issue is demonstrated by injecting payloads into the Special:RecentChanges page. The CVSS v3.1 base score is 7.4, indicating a high severity with network attack vector, low attack complexity, no privileges required, user interaction required, scope changed, and high confidentiality impact but no integrity or availability impact.

CWE-80Improper Neutralization of Script-Related HTML Tags in a Web Page (opens in a new tab)
Variant weaknessLikelihood of exploit: HighOWASP Top 10 A05:2025: Injection (opens in a new tab)
The product receives input from an upstream component, but it does not neutralize or incorrectly neutralizes special characters such as "<", ">", and "&" that could be interpreted as web-scripting elements when they are sent to a downstream component that processes web pages.
Implementation
Carefully check each input parameter against a rigorous positive specification (allowlist) defining the specific characters and format allowed. All input should be neutralized, not just parameters that the user is supposed to specify, but all data in the request, including hidden fields, cookies, headers, the URL…
Implementation · Output Encoding
Use and specify an output encoding that can be handled by the downstream component that is reading the output. Common encodings include ISO-8859-1, UTF-7, and UTF-8.
Implementation
With Struts, write all data from form beans with the bean's filter attribute set to true.
OWASP Cheat Sheets
Abuse Case (opens in a new tab)
Deserialization (opens in a new tab)
Cross Site Scripting Prevention (opens in a new tab)
DOM based XSS Prevention (opens in a new tab)
Injection Prevention (opens in a new tab)
OWASP ASVS 4.0.3
V1.5.1 (opens in a new tab)
V5.3.3 (opens in a new tab)
Attack patterns
XSS Targeting Non-Script Elements (opens in a new tab)
PHP Remote File Inclusion (opens in a new tab)
XSS Through HTTP Query Strings (opens in a new tab)
XSS Through HTTP Headers (opens in a new tab)
From MITRE CWE, MITRE CAPEC and OWASP (Top 10, OpenCRE).

References

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Exploitation evidence

What to do

Affected software

Description

AI analysisMachine-generated, updated 3 Nov 2026, 17:20 UTC

WeaknessesCWE-80

Technical details

References

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