High severity · published May 4, 2026
CVE-2026-23918
Apache HTTP Server: http2: double free and possible RCE on early reset
8.8
CVSS
49.7%
EPSS
No
On KEV
Description
Double Free and possible RCE vulnerability in Apache HTTP Server with the HTTP/2 protocol.
This issue affects Apache HTTP Server: 2.4.66.
Users are recommended to upgrade to version 2.4.67, which fixes the issue.
CVSS vector
CVSS:3.1/AV:N/AC:L/PR:L/UI:N/S:U/C:H/I:H/A:H
Attack vector
Network
Complexity
Low
Privileges
Low
User interaction
None
Confidentiality
High
Integrity
High
Availability
High
Scope
Unchanged
Exploitation
Is it being used?
Exploit prediction (EPSS)49.7% · higher than 99% of CVEs
Exploited in the wildNo evidence yet
CISA KEVNot listed
Ransomware campaign useNot known
Affected products
Which versions
HS
HTTP Server · Apache
2.4.66 · source: vendor, NVD
RH
Red Hat Hardened Images · Red Hat
All versions, or not specified · source: CISA
References
NVD
https://nvd.nist.gov/vuln/detail/CVE-2026-23918
CVE.org
https://www.cve.org/CVERecord?id=CVE-2026-23918
Vendor Advisory
https://httpd.apache.org/security/vulnerabilities_24.html
Mailing List
http://www.openwall.com/lists/oss-security/2026/05/04/19
access.redhat.com
https://access.redhat.com/errata/RHSA-2026:13938
access.redhat.com
https://access.redhat.com/security/cve/CVE-2026-23918
bugzilla.redhat.com
https://bugzilla.redhat.com/show_bug.cgi?id=2465304
security.access.redhat.com
https://security.access.redhat.com/data/csaf/v2/vex/2026/cve-2026-23918.json
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