Medium severity · published May 4, 2026
CVE-2026-33857
Apache HTTP Server: Off-by-one OOB reads in AJP getter functions
5.3
CVSS
0.4%
EPSS
No
On KEV
Description
Out-of-bounds Read vulnerability in mod_proxy_ajp of
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.
CVSS vector
CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:L/I:N/A:N
Attack vector
Network
Complexity
Low
Privileges
None
User interaction
None
Confidentiality
Low
Integrity
None
Availability
None
Scope
Unchanged
Exploitation
Is it being used?
Exploit prediction (EPSS)0.4% · higher than 33% of CVEs
Exploited in the wildNo evidence yet
CISA KEVNot listed
Ransomware campaign useNot known
Affected products
Which versions
HS
HTTP Server · Apache
through 2.4.66 · source: vendor, NVD
References
NVD
https://nvd.nist.gov/vuln/detail/CVE-2026-33857
CVE.org
https://www.cve.org/CVERecord?id=CVE-2026-33857
Vendor Advisory
https://httpd.apache.org/security/vulnerabilities_24.html
Mailing List
http://www.openwall.com/lists/oss-security/2026/05/04/15
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