VulnerabilityPublished 1 Jul 2026Updated 17 Oct 2026

CVE-2026-58033: mediawiki · Exposure of Sensitive Information to an Unauthorized Actor vulnerability in Wikimedia Foundation

Affects mediawikiSource GCVE Database

Authoritative record:CVE-2026-58033· Medium 5.3

Not known to be exploited · CVSS 5.3 Medium.

Data as of 26 Oct 2026, 17:16 UTC

CVSS 4.0 base score

5.3Medium

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

EPSS: 0.4% chance of exploitation in 30 days – higher than 35% of CVEsExploit Prediction Scoring System: the likelihood attackers will use this flaw soon.

CVSS:4.0/AV:N/AC:L/AT:N/PR:N/UI:P/VC:L/VI:N/VA:N/SC:N/SI:N/SA:N

Attack Vector: Network
Attack Complexity: Low
Attack Requirements: None
Privileges Required: None
User Interaction: Passive
Vulnerable system confidentiality: Low
Vulnerable system integrity: None
Vulnerable system availability: None
Subsequent system confidentiality: None
Subsequent system integrity: None
Subsequent system availability: None

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

Attack Vector: Network: The vulnerable system is bound to the network stack and the set of possible attackers extends beyond the other options listed below, 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: The attacker must take no measurable action to exploit the vulnerability. The attack requires no target-specific circumvention to exploit the vulnerability. An attacker can expect repeatable success against the vulnerable system.
Attack Requirements: None: The successful attack does not depend on the deployment and execution conditions of the vulnerable system. The attacker can expect to be able to reach the vulnerability and execute the exploit under all or most instances of the vulnerability.
Privileges Required: None: The attacker is unauthorized prior to attack, and therefore does not require any access to settings or files of the vulnerable system to carry out an attack.
User Interaction: Passive: Successful exploitation of this vulnerability requires limited interaction by the targeted user with the vulnerable system and the attacker’s payload. These interactions would be considered involuntary and do not require that the user actively subvert protections built into the vulnerable system.
Vulnerable system confidentiality: Low: There is some loss of confidentiality. Access to some restricted information is obtained, but the attacker does not have control over what information is obtained, or the amount or kind of loss is limited. The information disclosure does not cause a direct, serious loss to the Vulnerable System.
Vulnerable system integrity: None: There is no loss of integrity within the Vulnerable System.
Vulnerable system availability: None: There is no impact to availability within the Vulnerable System.
Subsequent system confidentiality: None: There is no loss of confidentiality within the Subsequent System or all confidentiality impact is constrained to the Vulnerable System.
Subsequent system integrity: None: There is no loss of integrity within the Subsequent System or all integrity impact is constrained to the Vulnerable System.
Subsequent system availability: None: There is no impact to availability within the Subsequent System or all availability impact is constrained to the Vulnerable System.

Definitions: FIRST CVSS v4.0 specification.

Exploitation evidence

Disclosed: evidence found.
CVE published 1 Jul 2026
Detectable: no evidence on record.
No public nuclei template indexed
Weaponised: 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 26 Oct 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.
Weaponised: Public exploit code exists in Metasploit or Exploit-DB, 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.

What to do

Affected software

Product	Affected	Fixed in
Ubuntu 26.10mediawiki`pkg:deb/ubuntu/mediawiki?arch=source&distro=stonking`Other threats	Affected =1:1.43.8+dfsg-2 =1:1.43.9+dfsg-1 =1:1.43.9+dfsg-1ubuntu1	Fixed in–
Ubuntu 26.04 LTSmediawiki`pkg:deb/ubuntu/mediawiki?arch=source&distro=resolute`Other threats	Affected 1:1.43.3+dfsg-1 – 1:1.43.8+dfsg-2 5 affected builds	Fixed in–
Ubuntu 25.10mediawiki`pkg:deb/ubuntu/mediawiki?arch=source&distro=questing`Other threats	Affected =1:1.43.1+dfsg-1 =1:1.43.1+dfsg-2 =1:1.43.3+dfsg-1	Fixed in–
Ubuntu Pro 24.04 LTSmediawiki`pkg:deb/ubuntu/mediawiki?arch=source&distro=esm-apps/noble`Other threats	Affected 1:1.39.4-2 – 1:1.39.7-1ubuntu0.1~esm1 5 affected builds	Fixed in–
Ubuntu Pro 22.04 LTSmediawiki`pkg:deb/ubuntu/mediawiki?arch=source&distro=esm-apps/jammy`Other threats	Affected 1:1.35.3-1 – 1:1.35.6-1ubuntu0.1~esm1 8 affected builds	Fixed in–
Ubuntu Pro 20.04 LTSmediawiki`pkg:deb/ubuntu/mediawiki?arch=source&distro=esm-apps/focal`Other threats	Affected 1:1.31.2-1ubuntu1 – 1:1.31.7-1ubuntu0.1~esm1 9 affected builds	Fixed in–

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

AI-suggested

Until an official fix is available, users should monitor for updates from Wikimedia Foundation and apply patches promptly once released.

Description

CVE-2026-58033 is a medium severity vulnerability in Wikimedia Foundation MediaWiki that allows unauthorized actors to access sensitive information. It affects multiple versions prior to 1.46.0, including specific older versions such as 1.45.4, 1.44.6, and 1.43.9. The vulnerability is related to the file includes/Actions/InfoAction.Php. The CVSS v3.1 score is 6.5, indicating a moderate impact. There is no explicit patch or remediation information provided in the source data.

Impact

Unauthorized actors may gain access to sensitive information within affected MediaWiki installations. The medium severity score reflects a moderate risk of information disclosure but does not indicate remote code execution or system compromise. There is no evidence of active exploitation in the wild.

Summary

This vulnerability in MediaWiki involves exposure of sensitive information due to a flaw in the InfoAction.Php file. It affects various versions prior to 1.46.0, including several Ubuntu-packaged versions. The CVSS 3.1 score of 6.5 classifies it as medium severity. No known exploits in the wild or vendor patch advisories are provided in the data. The vulnerability is publicly disclosed as of July 1, 2026.

References

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Exploitation evidence

What to do

Affected software

Description

AI analysisMachine-generated, updated 25 Oct 2026, 23:21 UTC

Technical details

References

Community reviews

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