Heap-based Buffer Overflow vulnerability in mod_proxy_ajp of Apache HTTP Server. If mod_proxy_ajp...

CVE-2026-28780 → View on GitHub ↗ View on CVE.org ↗ View on NVD ↗

Description

Heap-based Buffer Overflow vulnerability in mod_proxy_ajp of Apache HTTP Server.
If mod_proxy_ajp connects to a malicious AJP server this AJP server can send a malicious AJP message back to mod_proxy_ajp and cause it to write 4 attacker controlled bytes after the end of a heap based buffer.

This issue affects Apache HTTP Server: through 2.4.66.

Users are recommended to upgrade to version 2.4.67, which fixes the issue.

Basic information

Type
unreviewed
Severity
critical
Advisory on GitHub
Open advisory ↗
Repository advisory
—
Source code
Not specified
Published (advisory)
2026-05-06 00:31:33 UTC
Updated
2026-05-06 18:31:38 UTC
NVD published
2026-05-05

EPSS Score

Score Percentile
0.07% 20.88%

CVSS Scores

Base score Version Severity Vector
9.8 3.1 —
CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:H/A:H Click to expand
Attack vector (AV:N)
Could be attacked over the internet or any normal routed network—not just someone sitting at the machine.
Attack complexity (AC:L)
Once they can reach the bug, pulling it off is straightforward—no weird race conditions or rare setup.
Privileges required (PR:N)
No account or special rights needed—anonymous or random user is enough.
User interaction (UI:N)
Nobody has to click “OK” or open a trap file; it can work without a victim helping.
Scope (S:U)
Damage stays in the same “trust bubble” as the broken component—no big spill into unrelated systems.
Confidentiality (C:H)
Serious risk that confidential data gets exposed in a big way.
Integrity (I:H)
They could widely tamper with or forge data—trust in the data is badly hurt.
Availability (A:H)
Could take the service down hard or make it unusable for people who depend on it.

Identifiers

Type Value
GHSA GHSA-wpww-4qvv-xpv8 ↗
CVE CVE-2026-28780 ↗

CWEs

CWE id Name
CWE-122 Heap-based Buffer Overflow

References

cvelogic Threat Intelligence