Fix for additional cases of URL rewriting with ProxyPassMatch or

RewriteRule, where particular request-URIs could result in undesired
backend network exposure in some configurations. (CVE-2011-4317)

Thanks to Prutha Parikh from Qualys for reporting this issue.

* modules/proxy/mod_proxy.c (proxy_trans): Decline to handle the "*"
  request-URI.  Fail for cases where r->uri does not begin with a "/".

* modules/mappers/mod_rewrite.c (hook_uri2file): Likewise.

git-svn-id: https://svn.apache.org/repos/asf/httpd/httpd/trunk@1209432 13f79535-47bb-0310-9956-ffa450edef68

diff --git a/modules/mappers/mod_rewrite.c b/modules/mappers/mod_rewrite.c
index 470e01cdd31e5ed155e89939939b6606533d1123..d29cb454ef6786e3a179109238ba793361968fdb 100644 (file)
--- a/modules/mappers/mod_rewrite.c
+++ b/modules/mappers/mod_rewrite.c
@@ -4419,6 +4419,18 @@ static int hook_uri2file(request_rec *r)
         return DECLINED;
     }
 
+    if (strcmp(r->unparsed_uri, "*") == 0) {
+        /* Don't apply rewrite rules to "*". */
+        return DECLINED;
+    }
+
+    /* Check that the URI is valid. */
+    if (!r->uri || r->uri[0] != '/') {
+        ap_log_rerror(APLOG_MARK, APLOG_ERR, 0, r,
+                     "Invalid URI in request %s", r->the_request);
+        return HTTP_BAD_REQUEST;
+    }
+    
     /*
      *  add the SCRIPT_URL variable to the env. this is a bit complicated
      *  due to the fact that apache uses subrequests and internal redirects

diff --git a/modules/proxy/mod_proxy.c b/modules/proxy/mod_proxy.c
index 35195f8cce219ca97ad19a8bf7b022425749a0fa..8e90c9e340ab639d3409754bbcaeaea845b90f9b 100644 (file)
--- a/modules/proxy/mod_proxy.c
+++ b/modules/proxy/mod_proxy.c
@@ -655,6 +655,18 @@ static int proxy_trans(request_rec *r)
         return OK;
     }
 
+    if (strcmp(r->unparsed_uri, "*") == 0) {
+        /* "*" cannot be proxied. */
+        return DECLINED;
+    }
+
+    /* Check that the URI is valid. */
+    if (!r->uri || r->uri[0] != '/') {
+        ap_log_rerror(APLOG_MARK, APLOG_ERR, 0, r,
+                     "Invalid URI in request %s", r->the_request);
+        return HTTP_BAD_REQUEST;
+    }
+
     /* XXX: since r->uri has been manipulated already we're not really
      * compliant with RFC1945 at this point.  But this probably isn't
      * an issue because this is a hybrid proxy/origin server.