CVE-2004-0751

published 2004-10-20

CVE-2004-0751: The char_buffer_read function in the mod_ssl module for Apache 2.x, when using reverse proxying to an SSL server, allows remote attackers to cause a denial of…

Priority P3 37 medium 5 CVSS 2.0

AV N AC L Au N C N I N A P

EXPLOIT

The char_buffer_read function in the mod_ssl module for Apache 2.x, when using reverse proxying to an SSL server, allows remote attackers to cause a denial of service (segmentation fault).

Affected

2 ranges

Vendor	Product	Version range	Fixed in
apache	http_server	>= 2.0.44 < 2.0.51	2.0.51
debian	apache2	< apache2 2.0.50-11 (bookworm)	apache2 2.0.50-11 (bookworm)

Detection & IOCs extracted from sources · hover to see the quote

url http://www.example.com:47290/eRoomASP/CookieTest.asp?facility=facility&URL=%2FeRoom%2FFacility%2FRoom%2F0_4242↗

port 47290↗

• → Vulnerability is triggered via the 'char_buffer_read' function in 'ssl_engine_io.c' when Apache mod_ssl is configured as a reverse proxy (SSLProxyEngine on) to an SSL backend. Monitor for segmentation faults in Apache child processes under this configuration. ↗
• → The attack requires SSLProxyEngine and RewriteRule-based reverse proxying to an HTTPS target to be enabled. Audit httpd.conf for this combination as a prerequisite indicator. ↗
• → The DoS manifests as a segmentation fault in an Apache child process. Monitor Apache error logs for segfault entries correlated with inbound requests to SSL reverse-proxy endpoints. ↗

• · Vulnerability only affects Apache 2.x mod_ssl when configured as a reverse proxy to an SSL backend (SSLProxyEngine on). Instances not using SSL reverse proxying are not affected. ↗
• · Apache 2.0.50 is explicitly confirmed affected; other 2.x versions may also be vulnerable. ↗

CVSS provenance

nvd v2.0 5.0 MEDIUM AV:N/AC:L/Au:N/C:N/I:N/A:P

osv 5.0 MEDIUM

vendor_debian 5.0 MEDIUM

vendor_redhat 5.0 MEDIUM

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