CVE-2024-39573

Potential SSRF in mod_rewrite in Apache HTTP Server 2.4.59 and earlier allows an attacker to cause unsafe RewriteRules to unexpectedly setup URL's to be handled by mod_proxy. Users are recommended to upgrade to version 2.4.60, which fixes this issue.

Potential SSRF in mod_rewrite in Apache HTTP Server 2.4.59 and earlier allows an attacker to cause unsafe RewriteRules to unexpectedly setup URL's to be handled by mod_proxy. Users are recommended to upgrade to version 2.4.60, which fixes this issue.

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

Security Fix(es):

Improper escaping of output in mod_rewrite in Apache HTTP Server 2.4.59 and earlier allows an attacker to map URLs to filesystem locations that are permitted to be served by the server but are not intentionally/directly reachable by any URL, resulting in code execution or source code disclosure.

Substitutions in server context that use a backreferences or variables as the first segment of the substitution are affected.  Some unsafe RewiteRules will be broken by this change and the rewrite flag "UnsafePrefixStat" can be used to opt back in once ensuring the substitution is appropriately constrained.(CVE-2024-38475)

Potential SSRF in mod_rewrite in Apache HTTP Server 2.4.59 and earlier allows an attacker to cause unsafe RewriteRules to unexpectedly setup URL's to be handled by mod_proxy. Users are recommended to upgrade to version 2.4.60, which fixes this issue.(CVE-2024-39573)

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

Security Fix(es):

• httpd: Encoding problem in mod_proxy (CVE-2024-38473)

• httpd: Substitution encoding issue in mod_rewrite (CVE-2024-38474)

• httpd: Improper escaping of output in mod_rewrite (CVE-2024-38475)

• httpd: NULL pointer dereference in mod_proxy (CVE-2024-38477)

• httpd: Potential SSRF in mod_rewrite (CVE-2024-39573)

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.

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

Security Fix(es):

• httpd: Improper escaping of output in mod_rewrite (CVE-2024-38475)

• httpd: Substitution encoding issue in mod_rewrite (CVE-2024-38474)

• httpd: null pointer dereference in mod_proxy (CVE-2024-38477)

• httpd: Potential SSRF in mod_rewrite (CVE-2024-39573)

• httpd: Encoding problem in mod_proxy (CVE-2024-38473)

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.

Potential SSRF in mod_rewrite in Apache HTTP Server 2.4.59 and earlier allows an attacker to cause unsafe RewriteRules to unexpectedly setup URL's to be handled by mod_proxy. Users are recommended to upgrade to version 2.4.60, which fixes this issue.

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

Security Fix(es):

• httpd: Encoding problem in mod_proxy (CVE-2024-38473)
• httpd: Substitution encoding issue in mod_rewrite (CVE-2024-38474)
• httpd: Improper escaping of output in mod_rewrite (CVE-2024-38475)
• httpd: NULL pointer dereference in mod_proxy (CVE-2024-38477)
• httpd: Potential SSRF in mod_rewrite (CVE-2024-39573)

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.

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

Security Fix(es):

• httpd: Improper escaping of output in mod_rewrite (CVE-2024-38475)
• httpd: Substitution encoding issue in mod_rewrite (CVE-2024-38474)
• httpd: null pointer dereference in mod_proxy (CVE-2024-38477)
• httpd: Potential SSRF in mod_rewrite (CVE-2024-39573)
• httpd: Encoding problem in mod_proxy (CVE-2024-38473)

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.

Potential SSRF in mod_rewrite in Apache HTTP Server 2.4.59 and earlier allows an attacker to cause unsafe RewriteRules to unexpectedly setup URL's to be handled by mod_proxy. Users are recommended to upgrade to version 2.4.60, which fixes this issue.

• CVE-2024-38474: mod_rewrite: server weakness with encoded question marks in backreferences
• CVE-2024-38475: mod_rewrite: server weakness in mod_rewrite when first segment of substitution matches filesystem path
• CVE-2024-38477: mod_proxy: crash resulting in Denial of Service in mod_proxy via a malicious request
• CVE-2024-38476: http: server use exploitable/malicious backend application output to run local handlers via internal redirect
• CVE-2024-39573: mod_rewrite: proxy handler substitution

• CVE-2024-38474: mod_rewrite: server weakness with encoded question marks in backreferences
• CVE-2024-38475: mod_rewrite: server weakness in mod_rewrite when first segment of substitution matches filesystem path
• CVE-2024-38477: mod_proxy: crash resulting in Denial of Service in mod_proxy via a malicious request
• CVE-2023-38709: http_filters: HTTP response splitting
• CVE-2024-38473: mod_proxy: server proxy encoding problem
• CVE-2024-39573: mod_rewrite: proxy handler substitution
• CVE-2024-38476: http: server use exploitable/malicious backend application output to run local handlers via internal redirect
• CVE-2024-39884: modules: source code disclosure with handlers configured via AddType. Resolving regression introduced by CVE-2024-38476 fix
• CVE-2024-40725: modules: source code disclosure with handlers configured via AddType. Resolving regression introduced by CVE-2024-39884 fix

• CVE-2024-38474: mod_rewrite: server weakness with encoded question marks in backreferences
• CVE-2024-38475: mod_rewrite: server weakness in mod_rewrite when first segment of substitution matches filesystem path
• CVE-2024-38477: mod_proxy: crash resulting in Denial of Service in mod_proxy via a malicious request
• CVE-2023-38709: http_filters: HTTP response splitting
• CVE-2024-38473: mod_proxy: server proxy encoding problem
• CVE-2024-39573: mod_rewrite: proxy handler substitution
• CVE-2024-38476: http: server use exploitable/malicious backend application output to run local handlers via internal redirect
• CVE-2024-39884: modules: source code disclosure with handlers configured via AddType. Resolving regression introduced by CVE-2024-38476 fix
• CVE-2024-40725: modules: source code disclosure with handlers configured via AddType. Resolving regression introduced by CVE-2024-39884 fix

• CVE-2024-38474: mod_rewrite: server weakness with encoded question marks in backreferences
• CVE-2024-38475: mod_rewrite: server weakness in mod_rewrite when first segment of substitution matches filesystem path
• CVE-2024-38477: mod_proxy: crash resulting in Denial of Service in mod_proxy via a malicious request
• CVE-2023-38709: http_filters: HTTP response splitting
• CVE-2024-38473: mod_proxy: server proxy encoding problem
• CVE-2024-39573: mod_rewrite: proxy handler substitution
• CVE-2024-38476: http: server use exploitable/malicious backend application output to run local handlers via internal redirect
• CVE-2024-39884: modules: source code disclosure with handlers configured via AddType. Resolving regression introduced by CVE-2024-38476 fix
• CVE-2024-40725: modules: source code disclosure with handlers configured via AddType. Resolving regression introduced by CVE-2024-39884 fix

• CVE-2024-38474: mod_rewrite: server weakness with encoded question marks in backreferences
• CVE-2024-38475: mod_rewrite: server weakness in mod_rewrite when first segment of substitution matches filesystem path
• CVE-2024-38477: mod_proxy: crash resulting in Denial of Service in mod_proxy via a malicious request
• CVE-2024-38473: mod_proxy: server proxy encoding problem
• CVE-2024-39573: mod_rewrite: proxy handler substitution
• CVE-2024-38476: http: server use exploitable/malicious backend application output to run local handlers via internal redirect
• CVE-2024-39884: modules: source code disclosure with handlers configured via AddType. Resolving regression introduced by CVE-2024-38476 fix
• CVE-2024-40725: modules: source code disclosure with handlers configured via AddType. Resolving regression introduced by CVE-2024-39884 fix

• SECURITY UPDATE: potential SSRF via unsafe mod_rewrite substitution
  • debian/patches/CVE-2024-39573.patch: re-add the stripped per-directory prefix (or an implicit '/') to the substituted URI before it can be mistaken for a scheme:// proxy URL, in modules/mappers/mod_rewrite.c.
  • CVE-2024-39573
• SECURITY UPDATE: SSI #exec cmd query string passed to shell via mod_cgid
  • debian/patches/CVE-2025-58098.patch: do not pass r->args to create_argv() for SSI requests in modules/generators/mod_cgid.c.
  • CVE-2025-58098

• SECURITY UPDATE: potential SSRF via unsafe mod_rewrite substitution
  • debian/patches/CVE-2024-39573.patch: re-add the stripped per-directory prefix (or an implicit '/') to the substituted URI before it can be mistaken for a scheme:// proxy URL, in modules/mappers/mod_rewrite.c.
  • CVE-2024-39573
• SECURITY UPDATE: SSI #exec cmd query string passed to shell via mod_cgid
  • debian/patches/CVE-2025-58098.patch: do not pass r->args to create_argv() for SSI requests in modules/generators/mod_cgid.c.
  • CVE-2025-58098

• SECURITY UPDATE: potential SSRF in mod_rewrite via RewriteRule substitutions that produce a scheme-like target
  • debian/patches/CVE-2024-39573.patch: add the previously stripped per-directory prefix, or an implicit '/' root prefix, to the substituted URI before the query args are split in apply_rewrite_rule() in modules/mappers/mod_rewrite.c; otherwise a rule such as "RewriteRule ^/some/path(.*) $1" turns "/some/pathscheme:..." into the fully qualified URL "scheme:...", which mod_proxy then handles. Upstream fix 93aec0e3ca451bcc97f6d91c14d5399d13a73365 (SVN r1918600).
  • CVE-2024-39573
• SECURITY UPDATE: insufficient escaping of mod_ssl variables written to the log by CustomLog
  • debian/patches/CVE-2024-47252.patch: pass the results of ssl_var_log_handler_c() and ssl_var_log_handler_x() through ap_escape_logitem() in modules/ssl/ssl_engine_vars.c, so an untrusted TLS client can no longer insert escape characters into log files through the %{varname}c and %{varname}x formats logging mod_ssl variables such as SSL_TLS_SNI. Upstream fix c01e60707048be14a510f0a92128a5227923215c (SVN r1927042).
  • CVE-2024-47252
• SECURITY UPDATE: access control bypass by trusted clients through TLS 1.3 session resumption in mod_ssl
  • debian/patches/CVE-2025-23048.patch: move the ssl_server_compatible() check in ssl_hook_ReadReq() in modules/ssl/ssl_engine_kernel.c out of the SNI-present branch, so the handshake virtual host and the request virtual host are compared even when the client sent no SNI, as happens on a resumed TLS 1.3 session; previously such a request could reach a virtual host with different client certificate restrictions when SSLStrictSNIVHostCheck was off. Upstream fix c4cfa50c9068e8b8134c530ab21674e77d1278a2 (SVN r1927043).
  • CVE-2025-23048
• SECURITY UPDATE: denial of service through an assertion failure in mod_proxy_http2
  • debian/patches/CVE-2025-49630.patch: fall back to the server hostname when ProxyPreserveHost is on but the incoming request carried no Host: header, in open_stream() in modules/http2/h2_proxy_session.c, instead of passing a NULL authority on to the HTTP/2 backend and tripping an assertion. Upstream fix 88304321841a2fe8bd5eacc70e69418b0b545ca5 (SVN r1927044).
  • CVE-2025-49630
• SECURITY UPDATE: query string passed by mod_cgid to Server Side Includes #exec cmd= commands
  • debian/patches/CVE-2025-58098.patch: pass NULL instead of r->args to create_argv() for SSI_REQ requests in cgid_server(), and tolerate a NULL args in create_argv(), in modules/generators/mod_cgid.c; otherwise the shell-escaped query string is appended as arguments to the command line of an SSI "#exec cmd=..." directive. Upstream fix ecc1b8f3817e3dcab9c1f24f905752d3c0a279af (SVN r1930161).
  • CVE-2025-58098
• SECURITY UPDATE: integer overflow in the mod_md ACME renewal backoff timer
  • debian/patches/CVE-2025-55753.patch: double the retry delay step by step with an overflow and cap check in md_job_delay_on_errors() in modules/md/md_status.c instead of shifting job->min_delay left by err_count-1 in one go; otherwise after roughly 30 days of consecutive renewal failures the shift wraps the signed apr_time_t, the backoff collapses to 0 and the server retries against the ACME CA in a tight loop. Upstream fix 20666cfb765b8ad14efa3d97bc92d344b9395c89 (SVN r1929515).
  • CVE-2025-55753

Serving WebSocket protocol upgrades over a HTTP/2 connection could result in a Null Pointer dereference, leading to a crash of the server process, degrading performance. (CVE-2024-36387) Encoding problem in mod_proxy in Apache HTTP Server 2.4.59 and earlier allows request URLs with incorrect encoding to be sent to backend services, potentially bypassing authentication via crafted requests. (CVE-2024-38473) Substitution encoding issue in mod_rewrite in Apache HTTP Server 2.4.59 and earlier allows attacker to execute scripts in directories permitted by the configuration but not directly reachable by any URL or source disclosure of scripts meant to only to be executed as CGI. Some RewriteRules that capture and substitute unsafely will now fail unless rewrite flag "UnsafeAllow3F" is specified. (CVE-2024-38474) Improper escaping of output in mod_rewrite in Apache HTTP Server 2.4.59 and earlier allows an attacker to map URLs to filesystem locations that are permitted to be served by the server but are not intentionally/directly reachable by any URL, resulting in code execution or source code disclosure. Substitutions in server context that use a backreferences or variables as the first segment of the substitution are affected. Some unsafe RewiteRules will be broken by this change and the rewrite flag "UnsafePrefixStat" can be used to opt back in once ensuring the substitution is appropriately constrained. (CVE-2024-38475) Vulnerability in core of Apache HTTP Server 2.4.59 and earlier are vulnerably to information disclosure, SSRF or local script execution via backend applications whose response headers are malicious or exploitable. (CVE-2024-38476) Null pointer dereference in mod_proxy in Apache HTTP Server 2.4.59 and earlier allows an attacker to crash the server via a malicious request. (CVE-2024-38477) Potential SSRF in mod_rewrite in Apache HTTP Server 2.4.59 and earlier allows an attacker to cause unsafe RewriteRules to unexpectedly setup URL's to be handled by mod_proxy. (CVE-2024-39573) A regression in the core of Apache HTTP Server 2.4.60 ignores some use of the legacy content-type based configuration of handlers. "AddType" and similar configuration, under some circumstances where files are requested indirectly, result in source code disclosure of local content. For example, PHP scripts may be served instead of interpreted. (CVE-2024-39884)

These are all security issues fixed in the apache2-2.4.61-1.1 package on the GA media of openSUSE Tumbleweed.

This update for apache2 fixes the following issues:

• CVE-2024-38477: Fixed null pointer dereference in mod_proxy (bsc#1227270)
• CVE-2024-39573: Fixed potential SSRF in mod_rewrite (bsc#1227271)

This update for apache2 fixes the following issues:

Security fixes:

• CVE-2024-38477: Fixed null pointer dereference in mod_proxy (bsc#1227270)
• CVE-2024-39573: Fixed potential SSRF in mod_rewrite (bsc#1227271)
• CVE-2024-38475: Fixed improper escaping of output in mod_rewrite (bsc#1227268)

Other fixes:

• Fixed regression of security fix (bsc#1226217)

This update for apache2 fixes the following issues:

• CVE-2024-38475: Fixed improper escaping of output in mod_rewrite (bsc#1227268)
• CVE-2024-38476: Fixed server may use exploitable/malicious backend application output to run local handlers via internal redirect (bsc#1227269)
• CVE-2024-38477: Fixed null pointer dereference in mod_proxy (bsc#1227270)
• CVE-2024-39573: Fixed potential SSRF in mod_rewrite (bsc#1227271)

This update for apache2 fixes the following issues:

• CVE-2024-38477: Fixed null pointer dereference in mod_proxy (bsc#1227270).
• CVE-2024-39573: Fixed source code disclosure with handlers configured via AddType (bsc#1227271).
• CVE-2024-39884: Fixed source code disclosure of local content (bsc#1227353).
• CVE-2024-40725: Fixed potential SSRF in mod_rewrite (bsc#1228097).

Other bugfixes:

• Fixed a regression in module loading due to missing sym ap_thread_create (bsc#1233165).

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).

Marc Stern discovered that the Apache HTTP Server incorrectly handled serving WebSocket protocol upgrades over HTTP/2 connections. A remote attacker could possibly use this issue to cause the server to crash, resulting in a denial of service. (CVE-2024-36387)

Orange Tsai discovered that the Apache HTTP Server mod_proxy module incorrectly sent certain request URLs with incorrect encodings to backends. A remote attacker could possibly use this issue to bypass authentication. (CVE-2024-38473)

Orange Tsai discovered that the Apache HTTP Server mod_rewrite module incorrectly handled certain substitutions. A remote attacker could possibly use this issue to execute scripts in directories not directly reachable by any URL, or cause a denial of service. Some environments may require using the new UnsafeAllow3F flag to handle unsafe substitutions. (CVE-2024-38474, CVE-2024-38475, CVE-2024-39573)

Orange Tsai discovered that the Apache HTTP Server incorrectly handled certain response headers. A remote attacker could possibly use this issue to obtain sensitive information, execute local scripts, or perform SSRF attacks. (CVE-2024-38476)

Orange Tsai discovered that the Apache HTTP Server mod_proxy module incorrectly handled certain requests. A remote attacker could possibly use this issue to cause the server to crash, resulting in a denial of service. (CVE-2024-38477)

It was discovered that the Apache HTTP Server incorrectly handled certain handlers configured via AddType. A remote attacker could possibly use this issue to obtain source code. (CVE-2024-39884)

It was discovered that Apache HTTP Server incorrectly handled certain response headers. An attacker could possibly use this issue to perform HTTP response splitting attacks. This issue only affected Ubuntu 14.04 LTS. (CVE-2023-38709)

Will Dormann and David Warren discovered that Apache HTTP Server's HTTP/2 implementation did not properly reclaim memory when streams were reset by clients. A remote attacker could possibly use this issue to cause Apache HTTP Server to consume resources, leading to a denial of service. This issue only affected Ubuntu 18.04 LTS. (CVE-2023-45802)

Keran Mu and Jianjun Chen discovered that Apache HTTP Server incorrectly handled certain response headers. An attacker could possibly use this issue to perform HTTP response splitting attacks. This issue only affected Ubuntu 14.04 LTS. (CVE-2024-24795)

Orange Tsai discovered that Apache HTTP Server mod_proxy incorrectly handled URL encoding. A remote attacker could possibly use this issue to bypass authentication via crafted requests. This issue only affected Ubuntu 16.04 LTS and Ubuntu 18.04 LTS. (CVE-2024-38473)

Orange Tsai discovered that Apache HTTP Server could be caused to perform server-side request forgery (SSRF) via malicious backend response headers. A remote attacker could possibly use this issue to conduct SSRF attacks or disclose sensitive information. This issue only affected Ubuntu 14.04 LTS. (CVE-2024-38476)

Orange Tsai discovered that Apache HTTP Server mod_proxy did not properly handle certain null pointer conditions. A remote attacker could possibly use this issue to cause Apache HTTP Server to crash, resulting in a denial of service. This issue only affected Ubuntu 14.04 LTS. (CVE-2024-38477)

Orange Tsai discovered that Apache HTTP Server mod_rewrite could be made to perform server-side request forgery (SSRF) via unsafe RewriteRules. A remote attacker could possibly use this issue to conduct SSRF attacks. This issue only affected Ubuntu 16.04 LTS and Ubuntu 18.04 LTS. (CVE-2024-39573)

It was discovered that Apache HTTP Server incorrectly handled certain response headers. An attacker could possibly use this issue to perform HTTP response splitting attacks. This issue only affected Ubuntu 14.04 LTS. (CVE-2024-42516)

It was discovered that Apache HTTP Server could be caused to perform server-side request forgery (SSRF) via mod_headers modifying Content-Type headers. A remote attacker could possibly use this issue to conduct SSRF attacks. This issue only affected Ubuntu 14.04 LTS. (CVE-2024-43204)

John Runyon discovered that Apache HTTP Server mod_ssl did not properly escape user-supplied data before writing log entries. A remote attacker could possibly use this issue to insert escape sequences into log files. This issue only affected Ubuntu 14.04 LTS. (CVE-2024-47252)

Robert Merget discovered that Apache HTTP Server with SSLEngine optional was vulnerable to HTTP desynchronisation attacks. An attacker in a privileged network position could possibly use this issue to hijack HTTP sessions. This issue only affected Ubuntu 14.04 LTS. (CVE-2025-49812)

It was discovered that Apache HTTP Server mod_md had an integer overflow in the ACME certificate renewal backoff timer. An attacker could possibly use this issue to cause excessive certificate renewal requests. This issue only affected Ubuntu 20.04 LTS. (CVE-2025-55753)

Anthony Parfenov discovered that Apache HTTP Server with SSI enabled and mod_cgid passed shell-escaped query strings to #exec cmd directives. A remote attacker could possibly use this issue to perform command injection. (CVE-2025-58098)

Mattias Åsander discovered that Apache HTTP Server incorrectly gave precedence to environment variables from HTTP headers over server-calculated CGI variables. A remote attacker could possibly use this issue to influence the environment of CGI programs. (CVE-2025-65082)

Mattias Åsander discovered that Apache HTTP Server mod_userdir with suexec could be caused to run CGI scripts under…