CVE-2026-34059
📛 CVE Title
Apache HTTP Server: mod_proxy_ajp: Heap Over-Read and memory disclosure in ajp_parse_data()
Description
Buffer Over-read vulnerability in Apache HTTP Server. This issue affects Apache HTTP Server: through 2.4.66. Users are recommended to upgrade to version 2.4.67, which fixes the issue.
Overview
- State
- PUBLISHED
- Assigner (CNA)
- apache
- CVSS severity
- high
- CVSS score
- 7.5 / 10
- CVSS vector
AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:N/A:N- Effective score
- 7.5 / 10 HIGH source: CNA overview
- MSRC score
- 7.5 / 10 HIGH MS rating: Important
- CWE(s)
-
CWE-126 - Reserved
- 2026-03-25
- Published
- 2026-05-04 14:39 UTC
- Last updated
- 2026-05-04 19:32 UTC
- Source
- https://raw.githubusercontent.com/CVEProject/cvelistV5/main/cves/2026/34xxx/CVE-2026-34059.json
- Linked Threat
- CVE-2026-34059 — CVE-2026-34059
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
- 2026-05-04 13:16:00 UTC
- NVD last modified
- 2026-05-04 20:27:04 UTC
- NVD CVSS v3.1
- 7.5 / 10 HIGH source: 134c704f-9b21-4f2e-91b3-4a467353bcc0
- NVD CVSS vector
CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:N/A:N- Exploitability subscore
- 3.9 / 10
- Impact subscore
- 3.6 / 10
- EPSS score
- 0.0011 (probability of exploitation in next 30 days)
- EPSS percentile
- 28.12% vs all CVEs — higher = more likely to be exploited, as of 2026-05-24
NVD / KEV / EPSS data refreshed 2026-05-25 12:41 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-2026-26948 - Assigner
- apache
- Published
- May 4, 2026, 12:39:42 PM
- Updated
- May 4, 2026, 5:32:52 PM
- EUVD base score (CVSS 3.1)
-
7.5 / 10
CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:N/A:N - EUVD-reported EPSS
- 0.1100
- Vendors
- Apache Software Foundation
- Products
-
Apache HTTP Server (0 ≤2.4.66)
ENISA description: Buffer Over-read vulnerability in Apache HTTP Server. This issue affects Apache HTTP Server: through 2.4.66. Users are recommended to upgrade to version 2.4.67, which fixes the issue.
EUVD references (1)
Microsoft Security Response Center MSRC
Microsoft's vendor-authoritative record from the Security Update Guide — its own CVSS score, impact, severity rating, exploit assessment, and KB-article fixes. Refreshed 2026-08-15 03:01 UTC (source: CVRF).
- MS severity
- Important
- MS CVSS base score
- 7.5 / 10 (temporal 7.5)
CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:N/A:N - Release
- 2026-May
Microsoft remediations / KB articles (2)
- CBL-Mariner Releases — Vendor Fix / Security Update (fixed build 2.4.67-1)
- https://learn.microsoft.com/en-us/azure/azure-linux/tutorial-azure-linux-upgrade — None Available / CBL-Mariner Releases
Affected products (1)
| Vendor | Product | Versions | Platforms |
|---|---|---|---|
| Apache Software Foundation | Apache HTTP Server |
0 (affected)
|
— |
Affected products — CPE 2.3 (1) NVD
NVD's normalized CPE 2.3 matchers, used by vendor tools (vulnerability scanners, asset managers) for automated detection. Compare with the CNA's free-text "Affected products" section above.
cpe:2.3:a:apache:http_server:*:*:*:*:*:*:*:*
Vendor references (1)
References embedded in the original CVE record by the assigning CNA.
- https://httpd.apache.org/security/vulnerabilities_24.html vendor-advisory
MITRE references (1) cveawg.mitre.org
Pulled from MITRE's CVE Services API by the 🛰 Backfill from MITRE button.
- https://httpd.apache.org/security/vulnerabilities_24.html vendor-advisory
Web references (11)
DuckDuckGo results ranked by threat-intel / vendor advisory domains. Generated by the 🔎 Find references (web) button above — same flow as the Remediations search.
- MSRC update guide: CVE-2026-34059 msrc
- None Available msrc
- https://euvd.enisa.europa.eu/vulnerability/EUVD-2026-26948 rapid7:euvd.enisa.europa.eu
- http://cwe.mitre.org/data/definitions/126.html rapid7:cwe.mitre.org
- https://attackerkb.com/topics/CVE-2026-34059 rapid7:attackerkb.com
- https://security.alpinelinux.org/vuln/CVE-2026-34059 rapid7:security.alpinelinux.org
- http://www.openwall.com/lists/oss-security/2026/05/04/17 tenable:www.openwall.com
- https://nvd.nist.gov/vuln/detail/CVE-2026-34059 tenable:nvd.nist.gov
- https://www.securityweek.com/critical-high-severity-vulnerabilities-patched-in-apache-mina-http-server/ tenable:www.securityweek.com
- https://www.cve.org/CVERecord?id=CVE-2026-34059 tenable:www.cve.org
- https://www.first.org/epss/ tenable:www.first.org
NVD-tagged references (2)
Reference list NVD curates from the CNA record, vendor advisories, and third-party reports. The tag chips below are NVD's analyst-assigned categories.
- http://www.openwall.com/lists/oss-security/2026/05/04/17 af854a3a-2127-422b-91ae-364da2661108 Mailing ListThird Party Advisory
- https://httpd.apache.org/security/vulnerabilities_24.html security@apache.org Vendor Advisory
Remediations (17)
Remediations are stored against the linked Threat row; the list below is deduplicated across both pages.
-
web:app.opencve.io
Remediation No vendor fix or workaround currently provided. OpenCVE Recommended Actions Upgrade Apache HTTP Server to version 2.4.67 or later, which contains the fix for the heap over‑read in ajp_parse_data (). If the AJP protocol is not required for business operations, disable mod_proxy_ajp on the affected servers to eliminate the attack ...
2026-05-23 21:15 UTC -
web:krebsonsecurity.com
Microsoft expects that exploitation is more likely. May's Patch Tuesday is a welcome respite from April, which saw Microsoft fix a near-record 167 security flaws.
2026-05-23 21:15 UTC -
web:msrc.microsoft.com
Security Update Guide - Microsoft Security Response Center
2026-05-23 21:15 UTC -
web:nvd.nist.gov
An official website of the United States government Here's how you know
2026-05-23 21:15 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 21:15 UTC -
web:security-tracker.debian.org
Vulnerable and fixed packages The table below lists information on source packages.
2026-05-23 21:15 UTC -
web:vulert.com
Learn about CVE-2026-34059 , a heap over-read vulnerability in Apache HTTP Server's mod_proxy_ajp module, and how to fix it.
2026-05-23 21:15 UTC -
web:www.bleepingcomputer.com
Today is Microsoft's March 2026 Patch Tuesday with security updates for 79 flaws, including 2 publicly disclosed zero-day vulnerabilities.
2026-05-23 21:15 UTC -
web:www.crowdstrike.com
Microsoft has released security updates for 130 vulnerabilities, including 30 critical, in its May 2026 Patch Tuesday rollout.
2026-05-23 21:15 UTC -
web:www.thehackerwire.com
CVE-2026-34059 is a High severity vulnerability (CVSS 7.5). Buffer Over-read vulnerability in Apache HTTP Server. This issue affects Apache HTTP Server: through 2.4.66. Users are recommended to upgrade...
2026-05-23 21:15 UTC -
web:4sysops.com
Starting in April 2026 , Windows updates will change the default Kerberos ticket issuance behavior to AES-SHA1 for accounts without explicit encryption settings, while RC4 can still be used where explicitly enabled. This change, driven by CVE - 2026 -20833, affects every Windows Server environment where service accounts or devices still rely on RC4. Any service account, NAS device, or legacy ...
2026-05-26 02:46 UTC -
web:community.ui.com
Published: May 21, 2026 Updated: May 22, 2026 Version: 1.1 Revision: 1.1 Summary 1 of 5 A malicious actor with access to the network and high privileges could exploit an Improper Input Validation vulnerability found in UniFi OS devices to execute a Command Injection. Affected Products: UniFi OS Server (Version 5.0.6 and earlier) Mitigation : Update your UniFi OS Server to Version 5.0.8 or later ...
2026-05-26 02:46 UTC -
web:cve.akaoma.com
The exploitability of CVE-2026-34059 depends on two key factors: attack complexity (the level of effort required to execute an exploit) and privileges required (the access level an attacker needs). Exploitability Analysis for CVE-2026-34059 With low attack complexity and no required privileges, CVE-2026-34059 is an easy target for cybercriminals.
2026-05-26 02:46 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 .
2026-05-26 02:46 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 02:46 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.
2026-05-26 02:46 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 .
2026-05-26 02:46 UTC
AI Forensic Analysis
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Raw JSON
The full cvelistV5 record. Download as CVE-2026-34059.json.
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