CVE-2026-42536
CVE-2026-42536 is a high-severity vulnerability in Apache Http Server with a CVSS 3.x base score of 7.5. It is not currently listed as actively exploited by CISA, and its EPSS exploit-prediction score is low. The underlying weakness is classified as CWE-122.
Key facts
- Severity: High (CVSS 3.x base score 7.5)
- EPSS exploit prediction: 1% (49th percentile)
- Actively exploited: Not listed in CISA KEV
- EU (EUVD) id: EUVD-2026-35100
- Weakness: CWE-122
- Affected product: Apache Http Server
- Published:
- Last modified:
Description
Heap-based Buffer Overflow vulnerability in Apache HTTP Server with mod_xml2enc, xml2StartParse, and untrusted content This issue affects Apache HTTP Server: from 2.4.0 through 2.4.67. Users are recommended to upgrade to version 2.4.68, which fixes the issue.
Frequently asked questions
- What is CVE-2026-42536?
- Heap-based Buffer Overflow vulnerability in Apache HTTP Server with mod_xml2enc, xml2StartParse, and untrusted content This issue affects Apache HTTP Server: from 2.4.0 through 2.4.67. Users are recommended to upgrade to version 2.4.68, which fixes the issue.
- How severe is CVE-2026-42536?
- CVE-2026-42536 has a CVSS 3.x base score of 7.5, rated high severity. It is exploitable over network with low attack complexity, requires no privileges and no user interaction. Impact on confidentiality is none, integrity none, and availability high.
- Is CVE-2026-42536 being actively exploited?
- It is not currently listed in CISA's KEV catalog. Its EPSS exploit-prediction score is 1% (49th percentile), an estimate of the probability of exploitation in the next 30 days.
- What products are affected by CVE-2026-42536?
- CVE-2026-42536 affects Apache Http Server. See the affected-products list for the exact vulnerable versions.
- How do I fix CVE-2026-42536?
- Review the linked vendor and NVD advisories for patched versions and mitigations, then upgrade or apply the recommended workaround. Given its high severity, prioritise patching exposed systems.
- Does CVE-2026-42536 have an EU (EUVD) identifier?
- Yes. CVE-2026-42536 is tracked in the ENISA EU Vulnerability Database (EUVD) as EUVD-2026-35100.
- When was CVE-2026-42536 published?
- CVE-2026-42536 was published on 2026-06-08 and last updated on 2026-07-02.
References
- https://httpd.apache.org/security/vulnerabilities_24.html
- http://www.openwall.com/lists/oss-security/2026/06/08/9
- https://access.redhat.com/errata/RHSA-2026:34109
- https://access.redhat.com/security/cve/CVE-2026-42536
- https://bugzilla.redhat.com/show_bug.cgi?id=2486411
- https://security.access.redhat.com/data/csaf/v2/vex/2026/cve-2026-42536.json
Affected products (1)
- cpe:2.3:a:apache:http_server:*:*:*:*:*:*:*:*
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Threat intelligence
Threat-intel indicators referencing this CVE:
- 50.255.62.89 (ipv4-addr)
- 147.15.15.226 (ipv4-addr)
- 45.84.120.3 (ipv4-addr)
- 77.90.185.88 (ipv4-addr)
- 77.90.185.87 (ipv4-addr)
- 74.87.117.150 (ipv4-addr)
- 50.35.168.148 (ipv4-addr)
- 49.0.24.107 (ipv4-addr)