CVE-2026-34086
📛 CVE Title
AbuseFilter misuses ::userCanBitfield, exposing access-controlled information
Description
Vulnerability in Wikimedia Foundation AbuseFilter. This issue affects AbuseFilter: from * before 1.43.7, 1.44.4, 1.45.2.
Overview
- State
- PUBLISHED
- Assigner (CNA)
- wikimedia-foundation
- CVSS severity
- LOW
- CVSS score
- 2.1 / 10
- CVSS vector
CVSS:4.0/AV:N/AC:H/AT:P/PR:L/UI:P/VC:L/VI:L/VA:N/SC:L/SI:L/SA:N/S:N/AU:Y- Effective score
- 2.1 / 10 LOW source: CNA overview
- CWE(s)
- —
- Reserved
- 2026-03-25
- Published
- 2026-05-11 16:35 UTC
- Last updated
- 2026-05-11 19:33 UTC
- Source
- https://raw.githubusercontent.com/CVEProject/cvelistV5/main/cves/2026/34xxx/CVE-2026-34086.json
- Linked Threat
- CVE-2026-34086 — CVE-2026-34086
NVD triage scoring NVD CVE 2.0
Layer NVD adds on top of the CNA's CVE record — published / last-modified timestamps, exploitability / impact subscores, and the FIRST.org EPSS probability that this CVE will be exploited in the wild in the next 30 days.
- NVD published
- 2026-05-11 16:17:29 UTC
- NVD last modified
- 2026-05-12 14:45:49 UTC
- EPSS score
- 0.0009 (probability of exploitation in next 30 days)
- EPSS percentile
- 26.02% vs all CVEs — higher = more likely to be exploited, as of 2026-05-24
NVD-assigned CWE(s):
CWE-20
(differs from the CNA list above)
NVD / KEV / EPSS data refreshed 2026-05-25 12:39 UTC. Re-run the 🛰 Backfill from NVD button above to refresh.
European Union Vulnerability Database ENISA EUVD
ENISA's official EU repository for curated vulnerability intelligence. Carries a separate identifier (EUVD-YYYY-NNNN) and frequently exposes an earlier-published description + CVSS than NVD does.
- EUVD ID
-
EUVD-2026-29058 - Assigner
- wikimedia-foundation
- Published
- May 11, 2026, 2:35:15 PM
- Updated
- May 11, 2026, 5:33:27 PM
- EUVD base score (CVSS 4.0)
-
2.1 / 10
CVSS:4.0/AV:N/AC:H/AT:P/PR:L/UI:P/VC:L/VI:L/VA:N/SC:L/SI:L/SA:N/S:N/AU:Y - EUVD-reported EPSS
- 0.0900
- Vendors
- Wikimedia Foundation
- Products
-
AbuseFilter (* <1.43.7, 1.44.4, 1.45.2)
ENISA description: Vulnerability in Wikimedia Foundation AbuseFilter. This issue affects AbuseFilter: from * before 1.43.7, 1.44.4, 1.45.2.
EUVD references (1)
Affected products (1)
| Vendor | Product | Versions | Platforms |
|---|---|---|---|
| Wikimedia Foundation | AbuseFilter |
* (affected)
|
— |
Vendor references (1)
References embedded in the original CVE record by the assigning CNA.
MITRE references (1) cveawg.mitre.org
Pulled from MITRE's CVE Services API by the 🛰 Backfill from MITRE button.
Web references (3)
DuckDuckGo results ranked by threat-intel / vendor advisory domains. Generated by the 🔎 Find references (web) button above — same flow as the Remediations search.
- https://nvd.nist.gov/vuln/detail/CVE-2026-34086 tenable:nvd.nist.gov
- https://www.cve.org/CVERecord?id=CVE-2026-34086 tenable:www.cve.org
- https://www.first.org/epss/ tenable:www.first.org
NVD-tagged references (1)
Reference list NVD curates from the CNA record, vendor advisories, and third-party reports. The tag chips below are NVD's analyst-assigned categories.
- https://phabricator.wikimedia.org/T415584 c4f26cc8-17ff-4c99-b5e2-38fc1793eacc
Remediations (14)
Remediations are stored against the linked Threat row; the list below is deduplicated across both pages.
-
web:blog.qualys.com
With Qualys Policy Audit's out-of-the-box mitigation or Compensatory Controls, which reduce the risk of a vulnerability being exploited because the remediation ( fix / patch ) cannot be done immediately, these security controls are not recommended by any industry standards, such as CIS and DISA-STIG.
2026-05-23 20:57 UTC -
web:cyberpress.org
The U.S. Cybersecurity and Infrastructure Security Agency (CISA) has added two actively exploited Microsoft Defender vulnerabilities to its Known Exploited Vulnerabilities (KEV) catalog, issuing an urgent remediation directive for federal agencies with a due date of June 3, 2026 .
2026-05-23 20:57 UTC -
web:krebsonsecurity.com
For a clickable, per- patch breakdown, check out the SANS Internet Storm Center Patch Tuesday roundup. Running into problems applying any of these updates?
2026-05-23 20:57 UTC -
web:nvd.nist.gov
Official websites use .gov A .gov website belongs to an official government organization in the United States.
2026-05-23 20:57 UTC -
web:portal.msrc.microsoft.com
The Security Update Guide provides information on the latest Microsoft security updates, helping users understand and address potential vulnerabilities effectively.
2026-05-23 20:57 UTC -
web:www.cisecurity.org
<p>Multiple vulnerabilities have been discovered in Microsoft products, the most severe of which could allow for remote code execution. Successful exploitation of the most severe of these vulnerabilities could result in an attacker gaining the same privileges as the logged-on user. Depending on the privileges associated with the user, an attacker could then install programs; view, change, or ...
2026-05-23 20:57 UTC -
web:www.oracle.com
This Critical Patch Update contains 481 new security patches across the product families listed below. Please note that an MOS note summarizing the content of this Critical Patch Update and other Oracle Software Security Assurance activities is located at April 2026 Critical Patch Update: Executive Summary and Analysis.
2026-05-23 20:57 UTC -
web:www.techrepublic.com
Microsoft's April 2026 Patch Tuesday fixes 165 vulnerabilities, including two zero-days, in one of the company's largest monthly security updates.
2026-05-23 20:57 UTC -
web:www.windowslatest.com
Windows 11 April 2026 update adds Narrator Copilot support, faster Settings, File Explorer fixes, and key security improvements.
2026-05-23 20:57 UTC -
web:zecurit.com
Get the complete breakdown of Microsoft's May 2026 Patch Tuesday. We analyze the latest security updates and all critical CVEs .
2026-05-23 20:57 UTC -
web:msrc.microsoft.com
The Microsoft Security Response Center (MSRC) investigates all reports of security vulnerabilities affecting Microsoft products and services, and provides the information here as part of the ongoing effort to help you manage security risks and help keep your systems protected.
2026-05-26 02:51 UTC -
web:www.bleepingcomputer.com
Today is Microsoft's April 2026 Patch Tuesday with security updates for 167 flaws, including 2 zero-day vulnerabilities.
2026-05-26 02:51 UTC -
web:www.herodevs.com
A high-severity regression ( CVE - 2026 -34486) in Apache Tomcat's EncryptInterceptor allows unencrypted cluster messages to bypass encryption entirely. Learn the impact and how to remediate.
2026-05-26 02:51 UTC -
web:www.pcworld.com
This month's Patch Tuesday includes an actively exploited Office zero-day vulnerability and several critical RCE bugs in Windows and Remote Desktop.
2026-05-26 02:51 UTC
AI Forensic Analysis
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Raw JSON
The full cvelistV5 record. Download as CVE-2026-34086.json.
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