Return error if hostname too long for remote resolve

Resolves: RHEL-11467
2023-10-10 18:25:06 +02:00 · 2023-10-10 18:25:06 +02:00 · 0783247f07
commit 0783247f07
parent c20fcd3e87
2 changed files with 144 additions and 1 deletions
--- a/0033-curl-7.76.1-CVE-2023-38545.patch
+++ b/0033-curl-7.76.1-CVE-2023-38545.patch
@ -0,0 +1,136 @@
+From 1d66562c67fc0099d0fd882c693e51dd0b10c45c Mon Sep 17 00:00:00 2001
+From: Jay Satiro <raysatiro@yahoo.com>
+Date: Sat, 30 Sep 2023 03:40:02 -0400
+Subject: [PATCH] socks: return error if hostname too long for remote resolve
+
+Prior to this change the state machine attempted to change the remote
+resolve to a local resolve if the hostname was longer than 255
+characters. Unfortunately that did not work as intended and caused a
+security issue.
+
+Name resolvers cannot resolve hostnames longer than 255 characters.
+
+Bug: https://curl.se/docs/CVE-2023-38545.html
+---
+ lib/socks.c             |  8 +++---
+ tests/data/Makefile.inc |  2 +-
+ tests/data/test728      | 64 +++++++++++++++++++++++++++++++++++++++++
+ 3 files changed, 69 insertions(+), 5 deletions(-)
+ create mode 100644 tests/data/test728
+
+diff --git a/lib/socks.c b/lib/socks.c
+index c492d663c..a7b5ab07e 100644
+--- a/lib/socks.c
+++ b/lib/socks.c
+@@ -531,13 +531,13 @@ CURLproxycode Curl_SOCKS5(const char *proxy_user,
+       infof(data, "SOCKS5: connecting to HTTP proxy %s port %d\n",
+             hostname, remote_port);
+ 
+     /* RFC1928 chapter 5 specifies max 255 chars for domain name in packet */
+     if(!socks5_resolve_local && hostname_len > 255) {
+-      infof(data, "SOCKS5: server resolving disabled for hostnames of "
+-            "length > 255 [actual len=%zu]\n", hostname_len);
+-      socks5_resolve_local = TRUE;
+      failf(data, "SOCKS5: the destination hostname is too long to be "
+            "resolved remotely by the proxy.");
+      return CURLPX_LONG_HOSTNAME;
+     }
+ 
+     if(auth & ~(CURLAUTH_BASIC | CURLAUTH_GSSAPI))
+       infof(data,
+             "warning: unsupported value passed to CURLOPT_SOCKS5_AUTH: %lu\n",
+@@ -855,7 +855,7 @@ CONNECT_RESOLVE_REMOTE:
+ 
+     if(!socks5_resolve_local) {
+       socksreq[len++] = 3; /* ATYP: domain name = 3 */
+-      socksreq[len++] = (char) hostname_len; /* one byte address length */
+      socksreq[len++] = (unsigned char) hostname_len; /* one byte length */
+       memcpy(&socksreq[len], hostname, hostname_len); /* address w/o NULL */
+       len += hostname_len;
+       infof(data, "SOCKS5 connect to %s:%d (remotely resolved)\n",
+diff --git a/tests/data/Makefile.inc b/tests/data/Makefile.inc
+index 081e344d4..62ee53578 100644
+--- a/tests/data/Makefile.inc
+++ b/tests/data/Makefile.inc
+@@ -99,7 +99,7 @@ test672 test673 test674 test675 test676 test677 test678 test679 test680 \
+ \
+ test700 test701 test702 test703 test704 test705 test706 test707 test708 \
+ test709 test710 test711 test712 test713 test714 test715 test716 test717 \
+-test718 \
+test718 test728 \
+ \
+ test800 test801 test802 test803 test804 test805 test806 test807 test808 \
+ test809 test810 test811 test812 test813 test814 test815 test816 test817 \
+diff --git a/tests/data/test728 b/tests/data/test728
+new file mode 100644
+index 000000000..05bcf2883
+--- /dev/null
+++ b/tests/data/test728
+@@ -0,0 +1,64 @@
+<testcase>
+<info>
+<keywords>
+HTTP
+HTTP GET
+SOCKS5
+SOCKS5h
+followlocation
+</keywords>
+</info>
+
+#
+# Server-side
+<reply>
+# The hostname in this redirect is 256 characters and too long (> 255) for
+# SOCKS5 remote resolve. curl must return error CURLE_PROXY in this case.
+<data>
+HTTP/1.1 301 Moved Permanently
+Location: http://AAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAA/
+Content-Length: 0
+Connection: close
+
+</data>
+</reply>
+
+#
+# Client-side
+<client>
+<features>
+proxy
+</features>
+<server>
+http
+socks5
+</server>
+ <name>
+SOCKS5h with HTTP redirect to hostname too long
+ </name>
+ <command>
+--no-progress-meter --location --proxy socks5h://%HOSTIP:%SOCKSPORT http://%HOSTIP:%HTTPPORT/%TESTNUMBER
+</command>
+</client>
+
+#
+# Verify data after the test has been "shot"
+<verify>
+<protocol crlf="yes">
+GET /%TESTNUMBER HTTP/1.1
+Host: %HOSTIP:%HTTPPORT
+User-Agent: curl/%VERSION
+Accept: */*
+
+</protocol>
+<errorcode>
+97
+</errorcode>
+# the error message is verified because error code CURLE_PROXY (97) may be
+# returned for any number of reasons and we need to make sure it is
+# specifically for the reason below so that we know the check is working.
+<stderr mode="text">
+curl: (97) SOCKS5: the destination hostname is too long to be resolved remotely by the proxy.
+</stderr>
+</verify>
+</testcase>
+-- 
+2.42.0
+
--- a/curl.spec
+++ b/curl.spec
@ -1,7 +1,7 @@
 Summary: A utility for getting files from remote servers (FTP, HTTP, and others)
 Name: curl
 Version: 7.76.1
-Release: 27%{?dist}
+Release: 28%{?dist}
 License: MIT
 Source: https://curl.se/download/%{name}-%{version}.tar.xz

@ -98,6 +98,9 @@ Patch31:  0031-curl-7.76.1-CVE-2023-28321.patch
 # when keyboard-interactive auth fails, try password
 Patch32:  0032-curl-7.76.1-password-when-keyboard-interactive-fails.patch

+# return error if hostname too long for remote resolve
+Patch33:  0033-curl-7.76.1-CVE-2023-38545.patch
+
 # patch making libcurl multilib ready
 Patch101: 0101-curl-7.32.0-multilib.patch

@ -304,6 +307,7 @@ be installed.
 %patch30 -p1
 %patch31 -p1
 %patch32 -p1
+%patch33 -p1

 # Fedora patches
 %patch101 -p1
@ -529,6 +533,9 @@ rm -f ${RPM_BUILD_ROOT}%{_libdir}/libcurl.la
 %{_libdir}/libcurl.so.4.[0-9].[0-9].minimal

 %changelog
+* Tue Oct 10 2023 Jacek Migacz <jmigacz@redhat.com> - 7.76.1-28
+- return error if hostname too long for remote resolve (CVE-2023-38545)
+
 * Tue Sep 12 2023 Jacek Migacz <jmigacz@redhat.com> - 7.76.1-27
 - when keyboard-interactive auth fails, try password (#2229800)