Buffer overflow in Apache HTTP Server mod_proxy_html
CVE-2026-34355 is a moderate-severity buffer overflow vulnerability in the mod_proxy_html module of Apache HTTP Server. It affects Apache HTTP Server 2.4.67 and earlier, with supporting content indicating impact across the 2.4.x line up to 2.4.67. The flaw is triggered when mod_proxy_html processes content from an untrusted or malicious backend server, leading to memory corruption in the proxy HTML filtering path. Public reporting describes the issue as exploitable by an untrusted backend and capable of crashing the host process via crafted content manipulation. Apache fixed the issue in version 2.4.68.
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Exploits
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No public exploit code observed for this vulnerability.
Recent activity
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A buffer overflow vulnerability in Apache HTTP Server mod_proxy_html that can be exploited by an untrusted backend server.
A buffer overflow vulnerability in Apache HTTP Server's proxy HTML filter that can allow a malicious backend server to crash the host process via crafted content.
Vulnerability in Apache HTTP Server mod_proxy_html; exact impact is not fully recoverable from the provided text due to encoding issues, but it is listed among the fixed security issues in Apache 2.4.68.
Memory corruption vulnerability in Apache HTTP Server mod_proxy_html that could potentially allow code execution.
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Every observed campaign linking this CVE to a named adversary.
Malware families riding this exploit, with evidence and IOCs.
YARA, Sigma, Snort, and vendor rules, auto-deployed to your SIEM.
Cross-references every affected SKU, including bundled OEM variants.
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