CVE-2006-20001

A carefully crafted If: request header can cause a memory read, or write of a single zero byte, in a pool (heap) memory location beyond the header value sent. This could cause the process to crash.

This issue affects Apache HTTP Server 2.4.54 and earlier.

A carefully crafted If: request header can cause a memory read, or write of a single zero byte, in a pool (heap) memory location beyond the header value sent. This could cause the process to crash. This issue affects Apache HTTP Server 2.4.54 and earlier.

Apache HTTP Server is a powerful and flexible HTTP/1.1 compliant web server.

Security Fix(es):

Inconsistent Interpretation of HTTP Requests ('HTTP Request Smuggling') vulnerability in mod_proxy_ajp of Apache HTTP Server allows an attacker to smuggle requests to the AJP server it forwards requests to. This issue affects Apache HTTP Server Apache HTTP Server 2.4 version 2.4.54 and prior versions.(CVE-2022-36760)

Prior to Apache HTTP Server 2.4.55, a malicious backend can cause the response headers to be truncated early, resulting in some headers being incorporated into the response body. If the later headers have any security purpose, they will not be interpreted by the client.(CVE-2022-37436)

A carefully crafted If: request header can cause a memory read, or write of a single zero byte, in a pool (heap) memory location beyond the header value sent. This could cause the process to crash. This issue affects Apache HTTP Server 2.4.54 and earlier.(CVE-2006-20001)

The httpd packages provide the Apache HTTP Server, a powerful, efficient, and extensible web server.

Security Fix(es):

• httpd: mod_dav: out-of-bounds read/write of zero byte (CVE-2006-20001)

• httpd: mod_proxy_ajp: Possible request smuggling (CVE-2022-36760)

• httpd: mod_proxy: HTTP response splitting (CVE-2022-37436)

For more details about the security issue(s), including the impact, a CVSS score, acknowledgments, and other related information, refer to the CVE page(s) listed in the References section.

Bug Fix(es):

• httpd-init fails to create localhost.crt, localhost.key due to "sscg" default now creates a /dhparams.pem and is not idempotent if the file /dhparams.pem already exists. (BZ#2165967)

The httpd packages provide the Apache HTTP Server, a powerful, efficient, and extensible web server.

Security Fix(es):

• httpd: mod_dav: out-of-bounds read/write of zero byte (CVE-2006-20001)

• httpd: mod_proxy_ajp: Possible request smuggling (CVE-2022-36760)

• httpd: mod_proxy: HTTP response splitting (CVE-2022-37436)

For more details about the security issue(s), including the impact, a CVSS score, acknowledgments, and other related information, refer to the CVE page(s) listed in the References section.

Bug Fix(es):

• httpd-init fails to create localhost.crt, localhost.key due to "sscg" default now creates a /dhparams.pem and is not idempotent if the file /dhparams.pem already exists. (BZ#2165975)

A carefully crafted If: request header can cause a memory read, or write of a single zero byte, in a pool (heap) memory location beyond the header value sent. This could cause the process to crash. This issue affects Apache HTTP Server 2.4.54 and earlier.

The httpd packages provide the Apache HTTP Server, a powerful, efficient, and extensible web server.

Security Fix(es):

• httpd: mod_dav: out-of-bounds read/write of zero byte (CVE-2006-20001)
• httpd: mod_proxy_ajp: Possible request smuggling (CVE-2022-36760)
• httpd: mod_proxy: HTTP response splitting (CVE-2022-37436)

For more details about the security issue(s), including the impact, a CVSS score, acknowledgments, and other related information, refer to the CVE page(s) listed in the References section.

Bug Fix(es):

• httpd-init fails to create localhost.crt, localhost.key due to "sscg" default now creates a /dhparams.pem and is not idempotent if the file /dhparams.pem already exists. (BZ#2165967)

The httpd packages provide the Apache HTTP Server, a powerful, efficient, and extensible web server.

Security Fix(es):

• httpd: mod_dav: out-of-bounds read/write of zero byte (CVE-2006-20001)
• httpd: mod_proxy_ajp: Possible request smuggling (CVE-2022-36760)
• httpd: mod_proxy: HTTP response splitting (CVE-2022-37436)

For more details about the security issue(s), including the impact, a CVSS score, acknowledgments, and other related information, refer to the CVE page(s) listed in the References section.

Bug Fix(es):

• httpd-init fails to create localhost.crt, localhost.key due to "sscg" default now creates a /dhparams.pem and is not idempotent if the file /dhparams.pem already exists. (BZ#2165975)

• CVE-2022-37436: mod_proxy: HTTP response splitting
• CVE-2006-20001: mod_dav: out-of-bounds read/write

• CVE-2022-37436: mod_proxy: HTTP response splitting
• CVE-2006-20001: mod_dav: out-of-bounds read/write

• CVE-2006-20001: mod_dav: out-of-bounds read/write

• CVE-2006-20001: mod_dav: out-of-bounds read/write

• SECURITY UPDATE: out-of-bounds pool access in mod_dav If: header parsing
  • debian/patches/CVE-2006-20001.patch: confine the two-byte cursor advance to the "Not" branch and reject any other 'N'-prefixed token with HTTP 400 in dav_process_if_header() in modules/dav/main/util.c.
  • CVE-2006-20001

CVE-2022-37436: Apache HTTP Server: mod_proxy prior to 2.4.55 allows a backend to trigger HTTP response splitting. Prior to 2.4.55, a malicious backend can cause the response headers to be truncated early, resulting in some headers being incorporated into the response body. If the later headers have any security purpose, they will not be interpreted by the client. Credits: Dimas Fariski Setyawan Putra (@nyxsorcerer)

CVE-2022-36760: Apache HTTP Server: mod_proxy_ajp Possible request smuggling. Inconsistent Interpretation of HTTP Requests ('HTTP Request Smuggling') vulnerability in mod_proxy_ajp of Apache HTTP Server allows an attacker to smuggle requests to the AJP server it forwards requests to. Credits: ZeddYu_Lu from Qi'anxin Research Institute of Legendsec at Qi'anxin Group

CVE-2006-20001: mod_dav out of bounds read, or write of zero byte A carefully crafted If: request header can cause a memory read, or write of a single zero byte, in a pool (heap) memory location beyond the header value sent. This could cause the process to crash.

These are all security issues fixed in the apache2-2.4.55-1.1 package on the GA media of openSUSE Tumbleweed.

This update for apache2 fixes the following issues:

• CVE-2022-37436: Fixed an issue in mod_proxy where a malicious backend could cause the response headers to be truncated early, resulting in some headers being incorporated into the response body (bsc#1207251).
• CVE-2022-36760: Fixed an issue in mod_proxy_ajp that could allow request smuggling attacks (bsc#1207250).
• CVE-2006-20001: Fixed an issue in mod_proxy_ajp where a request header could cause memory corruption (bsc#1207247).

This update for apache2 fixes the following issues:

• CVE-2022-37436: Fixed an issue in mod_proxy where a malicious backend could cause the response headers to be truncated early, resulting in some headers being incorporated into the response body (bsc#1207251).
• CVE-2022-36760: Fixed an issue in mod_proxy_ajp that could allow request smuggling attacks (bsc#1207250).
• CVE-2006-20001: Fixed an issue in mod_proxy_ajp where a request header could cause memory corruption (bsc#1207247).

This update for apache2 fixes the following issues:

• CVE-2022-37436: Fixed an issue in mod_proxy where a malicious backend could cause the response headers to be truncated early, resulting in some headers being incorporated into the response body (bsc#1207251).
• CVE-2022-36760: Fixed an issue in mod_proxy_ajp that could allow request smuggling attacks (bsc#1207250).
• CVE-2006-20001: Fixed an issue in mod_proxy_ajp where a request header could cause memory corruption (bsc#1207247).

This update for apache2 fixes the following issues:

• CVE-2022-37436: Fixed an issue in mod_proxy where a malicious backend could cause the response headers to be truncated early, resulting in some headers being incorporated into the response body (bsc#1207251).
• CVE-2022-36760: Fixed an issue in mod_proxy_ajp that could allow request smuggling attacks (bsc#1207250).
• CVE-2006-20001: Fixed an issue in mod_proxy_ajp where a request header could cause memory corruption (bsc#1207247).

This update for apache2 fixes the following issues:

• CVE-2022-37436: Fixed an issue in mod_proxy where a malicious backend could cause the response headers to be truncated early, resulting in some headers being incorporated into the response body (bsc#1207251).
• CVE-2022-36760: Fixed an issue in mod_proxy_ajp that could allow request smuggling attacks (bsc#1207250).
• CVE-2006-20001: Fixed an issue in mod_proxy_ajp where a request header could cause memory corruption (bsc#1207247).

This update for apache2 fixes the following issues

• CVE-2026-23918: http2: double free and possible RCE on early reset (bsc#1263957).
• CVE-2026-24072: mod_rewrite elevation of privileges via ap_expr (bsc#1263935).
• CVE-2026-28780: heap buffer overflow in mod_proxy_ajp via ajp_msg_check_header() (bsc#1264163).
• CVE-2026-29167: mod_ldap per-dir use-after-free (bsc#1267976).
• CVE-2026-29168: allocation of resources without limits in mod_md via OCSP response (bsc#1264150).
• CVE-2026-29169: NULL pointer dereference in mod_dav_lock allows server crash via malicious requests (bsc#1263956).
• CVE-2026-29170: mod_proxy_ftp XSS (bsc#1267977).
• CVE-2026-33006: mod_auth_digest timing attack allows bypass of Digest authentication (bsc#1263955).
• CVE-2026-33007: NULL pointer dereference in mod_authn_socache allows unauthenticated remote user to crash a child processes (bsc#1263954).
• CVE-2026-33523: HTTP response splitting forwarding malicious status line (bsc#1263953).
• CVE-2026-33857: off-by-one OOB reads in AJP getter functions (bsc#1263952).
• CVE-2026-34032: heap buffer overread in mod_proxy_ajp due to missing null-termination check (bsc#1263951).
• CVE-2026-34059: heap buffer overread and memory disclosure via ajp_parse_data() (bsc#1263950).
• CVE-2026-34355: mod_proxy_html buffer overflow (bsc#1267978).
• CVE-2026-34356: malicious backend servers can lead to a heap-based buffer overflow (bsc#1267955).
• CVE-2026-42535: malicious path manipulation can lead to child process crashes (bsc#1267956).
• CVE-2026-42536: processing untrusted content can lead to a heap-based buffer overflow (bsc#1267962).
• CVE-2026-43951: out-of-bound read in merge_response_headers can cause crash (bsc#1267963).
• CVE-2026-44119: improper privilege management can lead to an unauthorized read (bsc#1267965).
• CVE-2026-44185: Stack Buffer Over-Read in mod_ssl OCSP send_request (bsc#1267969).
• CVE-2026-44186: responses from an attacker-controlled FTP backend can lead to resource exhaustion and a denial of service (bsc#1267970).
• CVE-2026-44631: crafted regular expression can lead to a buffer underwrite (bsc#1267971).
• CVE-2026-48913: file handle exhaustion during request processing in mod_http2 can lead to a use-after-free (bsc#1267972).
• CVE-2026-49975: Fix cookie header accounting against LimitRequestFields (bsc#1267503).

Non security issue:

• Update to 2.4.66 (jsc#PED-16334).

It was discovered that the Apache HTTP Server mod_dav module did not properly handle specially crafted request headers. A remote attacker could possibly use this issue to cause the process to crash, leading to a denial of service. (CVE-2006-20001)

It was discovered that the Apache HTTP Server mod_proxy_ajp module did not properly handle certain invalid Transfer-Encoding headers. A remote attacker could possibly use this issue to perform an HTTP Request Smuggling attack. (CVE-2022-36760)

It was discovered that the Apache HTTP Server mod_dav module incorrectly handled certain If: request headers. A remote attacker could possibly use this issue to cause the server to crash, resulting in a denial of service. (CVE-2006-20001)

ZeddYu_Lu discovered that the Apache HTTP Server mod_proxy_ajp module incorrectly interpreted certain HTTP Requests. A remote attacker could possibly use this issue to perform an HTTP Request Smuggling attack. (CVE-2022-36760)

Dimas Fariski Setyawan Putra discovered that the Apache HTTP Server mod_proxy module incorrectly truncated certain response headers. This may result in later headers not being interpreted by the client. (CVE-2022-37436)