Heap-based Buffer Overflow in Apache HTTP Server mod_proxy_ajp
CVE-2026-28780 is a heap-based buffer overflow in Apache HTTP Server's mod_proxy_ajp module. When mod_proxy_ajp connects to a malicious AJP back-end server, that server can return a crafted AJP message that triggers an out-of-bounds heap write in the AJP message handling path, including ajp_msg_check_header(). The flaw causes Apache HTTP Server to write 4 attacker-controlled bytes past the end of a heap-based buffer. The issue affects Apache HTTP Server through version 2.4.66 and is fixed in 2.4.67.
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Impact
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Exploits
No valid public exploits. Mallory filtered out 2 candidates as fakes, detection scripts, or README-only repos.
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Affected products & vendors
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Recent activity
21 sources tracked across advisories, community write-ups, and news. New activity surfaces here as Mallory finds it.
Unknown
A heap buffer overflow vulnerability in Apache HTTP Server mod_proxy_ajp that allows a malicious AJP server to overwrite heap memory.
A low-severity heap-based buffer overflow in Apache HTTP Server mod_proxy_ajp triggered by a malicious AJP server response.
A heap-based buffer overflow in Apache HTTP Server's mod_proxy_ajp that can be triggered when it connects to a malicious AJP server, allowing 4 attacker-controlled bytes to be written past the end of a heap buffer.
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Every observed campaign linking this CVE to a named adversary.
Malware families riding this exploit, with evidence and IOCs.
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Cross-references every affected SKU, including bundled OEM variants.
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