CVE-2026-33857
published 2026-05-04CVE-2026-33857: 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…
PriorityP430medium5.3CVSS 3.1
AVNACLPRNUINSUCLINAN
EPSS
0.39%
31.6th percentile
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.
Affected
5 ranges
| Vendor | Product | Version range | Fixed in |
|---|---|---|---|
| apache | http_server | < 2.4.67 | 2.4.67 |
| apache | httpd | — | — |
| apache_software_foundation | apache_http_server | <= 2.4.66 | — |
| httpd_2.4 | httpd | — | — |
| ubuntu | apache2 | — | — |
CVSS provenance
nvdv3.15.3MEDIUMCVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:L/I:N/A:N
vendor_ubuntu8.8HIGH
vendor_redhat5.3MEDIUM
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Ubuntu
Apache HTTP Server vulnerabilities
vendor_ubuntu·2026-05-06·CVSS 8.8
CVE-2026-28780 [HIGH] Apache HTTP Server vulnerabilities
Title: Apache HTTP Server vulnerabilities
Summary: Several security issues were fixed in Apache HTTP Server.
Bartlomiej Dmitruk and Stanislaw Strzalkowski discovered that Apache
HTTP Server incorrectly handled certain memory operations when using the
HTTP/2 protocol. A remote attacker could use this issue to cause Apache
HTTP Server to crash, resulting in a denial of service, or possibly execute
arbitrary code. This issue only affected Ubuntu 26.04 LTS.
(CVE-2026-23918)
It was discovered that the Apache HTTP Server mod_rewrite module
incorrectly handled certain privileges. A local attacker could possibly use
this issue to obtain sensitive information. (CVE-2026-24072)
Andrew Lacambra, Elhanan Haenel, Tianshuo Han, and Tristan Madani
discovered that the Apache HTTP Server mod_proxy_ajp
Red Hat
httpd: mod_proxy_ajp: off-by-one out-of-bounds reads in AJP getter functions
vendor_redhat·2026-05-04·CVSS 5.3
CVE-2026-33857 [MEDIUM] CWE-125 httpd: mod_proxy_ajp: off-by-one out-of-bounds reads in AJP getter functions
httpd: mod_proxy_ajp: off-by-one out-of-bounds reads in AJP getter functions
A flaw was found in the mod_proxy_ajp module of httpd. When processing AJP (Apache JServ Protocol) messages, the AJP getter functions attempt to read data beyond the allocated buffer size, allowing an attacker or a malformed request to cause an out-of-bounds read. This issue leads to a denial of service.
Statement: To exploit this issue, the Apache HTTP Server must be configured to connect to an untrusted or compromised AJP backend server, limiting its exposure. Due to this reason, this flaw has been rated with a moderate severity.
This flaw only affects configurations with mod_proxy_ajp loaded and being used. This module can be disabled via the configuration file if its functionality is not being used.
Mitigat
GHSA
GHSA-v5qg-p44g-5728: Out-of-bounds Read vulnerability in mod_proxy_ajp of
Apache HTTP Server
ghsa_unreviewed·2026-05-04
CVE-2026-33857 [MEDIUM] CWE-125 GHSA-v5qg-p44g-5728: Out-of-bounds Read vulnerability in mod_proxy_ajp of
Apache HTTP Server
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.
No detection rules found.
No public exploits indexed.
Bugzilla
CVE-2026-33857 httpd: off-by-one out-of-bounds reads in AJP getter functions [fedora-all]
bugzilla·2026-05-11·CVSS 5.3
CVE-2026-33857 [MEDIUM] CVE-2026-33857 httpd: off-by-one out-of-bounds reads in AJP getter functions [fedora-all]
CVE-2026-33857 httpd: off-by-one out-of-bounds reads in AJP getter functions [fedora-all]
Disclaimer: Community trackers are created by Red Hat Product Security team on a best effort basis. Package maintainers are required to ascertain if the flaw indeed affects their package, before starting the update process.
Bugzilla
CVE-2026-33857 httpd: mod_proxy_ajp: off-by-one out-of-bounds reads in AJP getter functions
bugzilla·2026-05-04·CVSS 5.3
CVE-2026-33857 [MEDIUM] CVE-2026-33857 httpd: mod_proxy_ajp: off-by-one out-of-bounds reads in AJP getter functions
CVE-2026-33857 httpd: mod_proxy_ajp: off-by-one out-of-bounds reads in AJP getter functions
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.
Rapid7
Patch Tuesday - May 2026
blogs_rapid7·2026-05-13·CVSS 10.0
CVE-2026-41089 [CRITICAL] Patch Tuesday - May 2026
Microsoft is publishing 137 vulnerabilities on May 2026 Patch Tuesday . Microsoft is not aware of exploitation in the wild or public disclosure for any of these vulnerabilities. So far this month, Microsoft has provided patches to address 133 browser vulnerabilities, which are not included in the Patch Tuesday count above.
## Windows Netlogon: critical RCE
Anyone responsible for securing a domain controller should prioritize remediation of CVE-2026-41089 , which is a critical stack-based buffer overflow in Windows Netlogon with a CVSS v3 base score of 9.8. Exploitation leads to execution in the context of the Netlogon service, so that’s SYSTEM privileges on the domain controller. For most pentesters, that’s the point at which the customer report more or less writes itself. No privileges
2026-05-04
Published