summaryrefslogtreecommitdiff
diff options
context:
space:
mode:
Diffstat
-rw-r--r--debian/changelog8
-rw-r--r--debian/patches/2019-5/0001-EAP-pwd-server-Fix-reassembly-buffer-handling.patch45
-rw-r--r--debian/patches/2019-5/0003-EAP-pwd-peer-Fix-reassembly-buffer-handling.patch45
-rw-r--r--debian/patches/2019-5/eap-pwd-message-reassembly-issue-with-unexpected-fragment.txt41
-rw-r--r--debian/patches/series2
-rw-r--r--src/eap_peer/eap_pwd.c9
-rw-r--r--src/eap_server/eap_server_pwd.c8
7 files changed, 156 insertions, 2 deletions
diff --git a/debian/changelog b/debian/changelog
index d4d0a8e..35a81f4 100644
--- a/debian/changelog
+++ b/debian/changelog
@@ -1,3 +1,11 @@
+wpa (2:2.7+git20190128+0c1e29f-5) unstable; urgency=high
+
+ * Fix security issue 2019-5:
+ - EAP-pwd message reassembly issue with unexpected fragment
+ (Closes: #927463, no CVE assigned).
+
+ -- Andrej Shadura <andrewsh@debian.org> Fri, 26 Apr 2019 14:55:52 +0200
+
wpa (2:2.7+git20190128+0c1e29f-4) unstable; urgency=high
* Apply security fixes (Closes: #926801):
diff --git a/debian/patches/2019-5/0001-EAP-pwd-server-Fix-reassembly-buffer-handling.patch b/debian/patches/2019-5/0001-EAP-pwd-server-Fix-reassembly-buffer-handling.patch
new file mode 100644
index 0000000..620d67d
--- /dev/null
+++ b/debian/patches/2019-5/0001-EAP-pwd-server-Fix-reassembly-buffer-handling.patch
@@ -0,0 +1,45 @@
+From fe76f487e28bdc61940f304f153a954cf36935ea Mon Sep 17 00:00:00 2001
+From: Jouni Malinen <jouni@codeaurora.org>
+Date: Wed, 17 Apr 2019 01:55:32 +0300
+Subject: [PATCH 1/3] EAP-pwd server: Fix reassembly buffer handling
+
+data->inbuf allocation might fail and if that were to happen, the next
+fragment in the exchange could have resulted in NULL pointer
+dereference. Unexpected fragment with more bit might also be able to
+trigger this. Fix that by explicitly checking for data->inbuf to be
+available before using it.
+
+Signed-off-by: Jouni Malinen <jouni@codeaurora.org>
+---
+ src/eap_server/eap_server_pwd.c | 8 +++++++-
+ 1 file changed, 7 insertions(+), 1 deletion(-)
+
+diff --git a/src/eap_server/eap_server_pwd.c b/src/eap_server/eap_server_pwd.c
+index 11bef55..38e2af8 100644
+--- a/src/eap_server/eap_server_pwd.c
++++ b/src/eap_server/eap_server_pwd.c
+@@ -912,6 +912,12 @@ static void eap_pwd_process(struct eap_sm *sm, void *priv,
+ * the first and all intermediate fragments have the M bit set
+ */
+ if (EAP_PWD_GET_MORE_BIT(lm_exch) || data->in_frag_pos) {
++ if (!data->inbuf) {
++ wpa_printf(MSG_DEBUG,
++ "EAP-pwd: No buffer for reassembly");
++ eap_pwd_state(data, FAILURE);
++ return;
++ }
+ if ((data->in_frag_pos + len) > wpabuf_size(data->inbuf)) {
+ wpa_printf(MSG_DEBUG, "EAP-pwd: Buffer overflow "
+ "attack detected! (%d+%d > %d)",
+@@ -932,7 +938,7 @@ static void eap_pwd_process(struct eap_sm *sm, void *priv,
+ * last fragment won't have the M bit set (but we're obviously
+ * buffering fragments so that's how we know it's the last)
+ */
+- if (data->in_frag_pos) {
++ if (data->in_frag_pos && data->inbuf) {
+ pos = wpabuf_head_u8(data->inbuf);
+ len = data->in_frag_pos;
+ wpa_printf(MSG_DEBUG, "EAP-pwd: Last fragment, %d bytes",
+--
+2.7.4
+
diff --git a/debian/patches/2019-5/0003-EAP-pwd-peer-Fix-reassembly-buffer-handling.patch b/debian/patches/2019-5/0003-EAP-pwd-peer-Fix-reassembly-buffer-handling.patch
new file mode 100644
index 0000000..1a23e0f
--- /dev/null
+++ b/debian/patches/2019-5/0003-EAP-pwd-peer-Fix-reassembly-buffer-handling.patch
@@ -0,0 +1,45 @@
+From d2d1a324ce937628e4d9d9999fe113819b7d4478 Mon Sep 17 00:00:00 2001
+From: Jouni Malinen <jouni@codeaurora.org>
+Date: Wed, 17 Apr 2019 02:21:20 +0300
+Subject: [PATCH 3/3] EAP-pwd peer: Fix reassembly buffer handling
+
+Unexpected fragment might result in data->inbuf not being allocated
+before processing and that could have resulted in NULL pointer
+dereference. Fix that by explicitly checking for data->inbuf to be
+available before using it.
+
+Signed-off-by: Jouni Malinen <jouni@codeaurora.org>
+---
+ src/eap_peer/eap_pwd.c | 9 ++++++++-
+ 1 file changed, 8 insertions(+), 1 deletion(-)
+
+diff --git a/src/eap_peer/eap_pwd.c b/src/eap_peer/eap_pwd.c
+index 46894a5..76fcad4 100644
+--- a/src/eap_peer/eap_pwd.c
++++ b/src/eap_peer/eap_pwd.c
+@@ -932,6 +932,13 @@ eap_pwd_process(struct eap_sm *sm, void *priv, struct eap_method_ret *ret,
+ * buffer and ACK the fragment
+ */
+ if (EAP_PWD_GET_MORE_BIT(lm_exch) || data->in_frag_pos) {
++ if (!data->inbuf) {
++ wpa_printf(MSG_DEBUG,
++ "EAP-pwd: No buffer for reassembly");
++ ret->methodState = METHOD_DONE;
++ ret->decision = DECISION_FAIL;
++ return NULL;
++ }
+ data->in_frag_pos += len;
+ if (data->in_frag_pos > wpabuf_size(data->inbuf)) {
+ wpa_printf(MSG_INFO, "EAP-pwd: Buffer overflow attack "
+@@ -958,7 +965,7 @@ eap_pwd_process(struct eap_sm *sm, void *priv, struct eap_method_ret *ret,
+ /*
+ * we're buffering and this is the last fragment
+ */
+- if (data->in_frag_pos) {
++ if (data->in_frag_pos && data->inbuf) {
+ wpa_printf(MSG_DEBUG, "EAP-pwd: Last fragment, %d bytes",
+ (int) len);
+ pos = wpabuf_head_u8(data->inbuf);
+--
+2.7.4
+
diff --git a/debian/patches/2019-5/eap-pwd-message-reassembly-issue-with-unexpected-fragment.txt b/debian/patches/2019-5/eap-pwd-message-reassembly-issue-with-unexpected-fragment.txt
new file mode 100644
index 0000000..5366f78
--- /dev/null
+++ b/debian/patches/2019-5/eap-pwd-message-reassembly-issue-with-unexpected-fragment.txt
@@ -0,0 +1,41 @@
+EAP-pwd message reassembly issue with unexpected fragment
+
+Published: April 18, 2019
+Latest version available from: https://w1.fi/security/2019-5/
+
+Vulnerability
+
+EAP-pwd implementation in hostapd (EAP server) and wpa_supplicant (EAP
+peer) was discovered not to validate fragmentation reassembly state
+properly for a case where an unexpected fragment could be received. This
+could result in process termination due to NULL pointer dereference.
+
+An attacker in radio range of a station device with wpa_supplicant
+network profile enabling use of EAP-pwd could cause the wpa_supplicant
+process to terminate by constructing unexpected sequence of EAP
+messages. An attacker in radio range of an access point that points to
+hostapd as an authentication server with EAP-pwd user enabled in runtime
+configuration (or in non-WLAN uses of EAP authentication as long as the
+attacker can send EAP-pwd messages to the server) could cause the
+hostapd process to terminate by constructing unexpected sequence of EAP
+messages.
+
+
+Vulnerable versions/configurations
+
+All hostapd and wpa_supplicant versions with EAP-pwd support
+(CONFIG_EAP_PWD=y in the build configuration and EAP-pwd being enabled
+in the runtime configuration) are vulnerable against the process
+termination (denial of service) attack.
+
+
+Possible mitigation steps
+
+- Merge the following commits to wpa_supplicant/hostapd and rebuild:
+
+ EAP-pwd peer: Fix reassembly buffer handling
+ EAP-pwd server: Fix reassembly buffer handling
+
+ These patches are available from https://w1.fi/security/2019-5/
+
+- Update to wpa_supplicant/hostapd v2.8 or newer, once available
diff --git a/debian/patches/series b/debian/patches/series
index 5f09aea..ca66b1d 100644
--- a/debian/patches/series
+++ b/debian/patches/series
@@ -22,3 +22,5 @@ fix-ENGINE-support-with-openssl-1.1.patch
2019-sae-eap/0012-EAP-pwd-server-Detect-reflection-attacks.patch
2019-sae-eap/0013-EAP-pwd-client-Verify-received-scalar-and-element.patch
2019-sae-eap/0014-EAP-pwd-Check-element-x-y-coordinates-explicitly.patch
+2019-5/0001-EAP-pwd-server-Fix-reassembly-buffer-handling.patch
+2019-5/0003-EAP-pwd-peer-Fix-reassembly-buffer-handling.patch
diff --git a/src/eap_peer/eap_pwd.c b/src/eap_peer/eap_pwd.c
index f37b974..5758307 100644
--- a/src/eap_peer/eap_pwd.c
+++ b/src/eap_peer/eap_pwd.c
@@ -969,6 +969,13 @@ eap_pwd_process(struct eap_sm *sm, void *priv, struct eap_method_ret *ret,
* buffer and ACK the fragment
*/
if (EAP_PWD_GET_MORE_BIT(lm_exch) || data->in_frag_pos) {
+ if (!data->inbuf) {
+ wpa_printf(MSG_DEBUG,
+ "EAP-pwd: No buffer for reassembly");
+ ret->methodState = METHOD_DONE;
+ ret->decision = DECISION_FAIL;
+ return NULL;
+ }
data->in_frag_pos += len;
if (data->in_frag_pos > wpabuf_size(data->inbuf)) {
wpa_printf(MSG_INFO, "EAP-pwd: Buffer overflow attack "
@@ -995,7 +1002,7 @@ eap_pwd_process(struct eap_sm *sm, void *priv, struct eap_method_ret *ret,
/*
* we're buffering and this is the last fragment
*/
- if (data->in_frag_pos) {
+ if (data->in_frag_pos && data->inbuf) {
wpa_printf(MSG_DEBUG, "EAP-pwd: Last fragment, %d bytes",
(int) len);
pos = wpabuf_head_u8(data->inbuf);
diff --git a/src/eap_server/eap_server_pwd.c b/src/eap_server/eap_server_pwd.c
index f6c75cf..fc497bb 100644
--- a/src/eap_server/eap_server_pwd.c
+++ b/src/eap_server/eap_server_pwd.c
@@ -947,6 +947,12 @@ static void eap_pwd_process(struct eap_sm *sm, void *priv,
* the first and all intermediate fragments have the M bit set
*/
if (EAP_PWD_GET_MORE_BIT(lm_exch) || data->in_frag_pos) {
+ if (!data->inbuf) {
+ wpa_printf(MSG_DEBUG,
+ "EAP-pwd: No buffer for reassembly");
+ eap_pwd_state(data, FAILURE);
+ return;
+ }
if ((data->in_frag_pos + len) > wpabuf_size(data->inbuf)) {
wpa_printf(MSG_DEBUG, "EAP-pwd: Buffer overflow "
"attack detected! (%d+%d > %d)",
@@ -967,7 +973,7 @@ static void eap_pwd_process(struct eap_sm *sm, void *priv,
* last fragment won't have the M bit set (but we're obviously
* buffering fragments so that's how we know it's the last)
*/
- if (data->in_frag_pos) {
+ if (data->in_frag_pos && data->inbuf) {
pos = wpabuf_head_u8(data->inbuf);
len = data->in_frag_pos;
wpa_printf(MSG_DEBUG, "EAP-pwd: Last fragment, %d bytes",
generated by cgit v1.2.3 (git 2.25.1) at 2024-06-02 16:49:12 +0000