* [PATCH 1/2] openssh: fix for CVE-2014-2532
2014-05-13 7:46 [PATCH 0/2] openssh: two CVE fixes Chen Qi
@ 2014-05-13 7:46 ` Chen Qi
2014-05-13 7:46 ` [PATCH 2/2] openssh: fix for CVE-2014-2653 Chen Qi
1 sibling, 0 replies; 3+ messages in thread
From: Chen Qi @ 2014-05-13 7:46 UTC (permalink / raw)
To: openembedded-core
sshd in OpenSSH before 6.6 does not properly support wildcards on
AcceptEnv lines in sshd_config, which allows remote attackers to
bypass intended environment restrictions by using a substring located
before a wildcard character.
Signed-off-by: Chen Qi <Qi.Chen@windriver.com>
---
.../openssh/openssh/openssh-CVE-2014-2532.patch | 22 ++++++++++++++++++++
meta/recipes-connectivity/openssh/openssh_6.5p1.bb | 3 ++-
2 files changed, 24 insertions(+), 1 deletion(-)
create mode 100644 meta/recipes-connectivity/openssh/openssh/openssh-CVE-2014-2532.patch
diff --git a/meta/recipes-connectivity/openssh/openssh/openssh-CVE-2014-2532.patch b/meta/recipes-connectivity/openssh/openssh/openssh-CVE-2014-2532.patch
new file mode 100644
index 0000000..3deaf3f
--- /dev/null
+++ b/meta/recipes-connectivity/openssh/openssh/openssh-CVE-2014-2532.patch
@@ -0,0 +1,22 @@
+Upstream-Status: Backport
+
+Fix for CVE-2014-2532
+
+Backported from openssh-6.6p1.tar.gz
+
+Signed-off-by: Chen Qi <Qi.Chen@windriver.com>
+---
+--- a/session.c
++++ b/session.c
+@@ -955,6 +955,11 @@
+ u_int envsize;
+ u_int i, namelen;
+
++ if (strchr(name, '=') != NULL) {
++ error("Invalid environment variable \"%.100s\"", name);
++ return;
++ }
++
+ /*
+ * If we're passed an uninitialized list, allocate a single null
+ * entry before continuing.
diff --git a/meta/recipes-connectivity/openssh/openssh_6.5p1.bb b/meta/recipes-connectivity/openssh/openssh_6.5p1.bb
index b93b9ae..230f38a 100644
--- a/meta/recipes-connectivity/openssh/openssh_6.5p1.bb
+++ b/meta/recipes-connectivity/openssh/openssh_6.5p1.bb
@@ -29,7 +29,8 @@ SRC_URI = "ftp://ftp.openbsd.org/pub/OpenBSD/OpenSSH/portable/openssh-${PV}.tar.
file://sshdgenkeys.service \
file://volatiles.99_sshd \
file://add-test-support-for-busybox.patch \
- file://run-ptest"
+ file://run-ptest \
+ file://openssh-CVE-2014-2532.patch"
PAM_SRC_URI = "file://sshd"
--
1.7.9.5
^ permalink raw reply related [flat|nested] 3+ messages in thread* [PATCH 2/2] openssh: fix for CVE-2014-2653
2014-05-13 7:46 [PATCH 0/2] openssh: two CVE fixes Chen Qi
2014-05-13 7:46 ` [PATCH 1/2] openssh: fix for CVE-2014-2532 Chen Qi
@ 2014-05-13 7:46 ` Chen Qi
1 sibling, 0 replies; 3+ messages in thread
From: Chen Qi @ 2014-05-13 7:46 UTC (permalink / raw)
To: openembedded-core
The verify_host_key function in sshconnect.c in the client in OpenSSH 6.6 and
earlier allows remote servers to trigger the skipping of SSHFP DNS RR checking
by presenting an unacceptable HostCertificate.
Signed-off-by: Chen Qi <Qi.Chen@windriver.com>
---
.../openssh/openssh/openssh-CVE-2014-2653.patch | 114 ++++++++++++++++++++
meta/recipes-connectivity/openssh/openssh_6.5p1.bb | 3 +-
2 files changed, 116 insertions(+), 1 deletion(-)
create mode 100644 meta/recipes-connectivity/openssh/openssh/openssh-CVE-2014-2653.patch
diff --git a/meta/recipes-connectivity/openssh/openssh/openssh-CVE-2014-2653.patch b/meta/recipes-connectivity/openssh/openssh/openssh-CVE-2014-2653.patch
new file mode 100644
index 0000000..674d186
--- /dev/null
+++ b/meta/recipes-connectivity/openssh/openssh/openssh-CVE-2014-2653.patch
@@ -0,0 +1,114 @@
+Upstream-Status: Backport
+
+This CVE could be removed if openssh is upgrade to 6.6 or higher.
+Below are some details.
+
+Attempt SSHFP lookup even if server presents a certificate
+
+Reference:
+https://bugs.debian.org/cgi-bin/bugreport.cgi?bug=742513
+
+If an ssh server presents a certificate to the client, then the client
+does not check the DNS for SSHFP records. This means that a malicious
+server can essentially disable DNS-host-key-checking, which means the
+client will fall back to asking the user (who will just say "yes" to
+the fingerprint, sadly).
+
+This patch means that the ssh client will, if necessary, extract the
+server key from the proffered certificate, and attempt to verify it
+against the DNS. The patch was written by Mark Wooding
+<mdw@distorted.org.uk>. I modified it to add one debug2 call, reviewed
+it, and tested it.
+
+Signed-off-by: Matthew Vernon <matthew@debian.org>
+Signed-off-by: Chen Qi <Qi.Chen@windriver.com>
+---
+--- a/sshconnect.c
++++ b/sshconnect.c
+@@ -1210,36 +1210,63 @@ fail:
+ return -1;
+ }
+
++static int
++check_host_key_sshfp(char *host, struct sockaddr *hostaddr, Key *host_key)
++{
++ int rc = -1;
++ int flags = 0;
++ Key *raw_key = NULL;
++
++ if (!options.verify_host_key_dns)
++ goto done;
++
++ /* XXX certs are not yet supported for DNS; try looking the raw key
++ * up in the DNS anyway.
++ */
++ if (key_is_cert(host_key)) {
++ debug2("Extracting key from cert for SSHFP lookup");
++ raw_key = key_from_private(host_key);
++ if (key_drop_cert(raw_key))
++ fatal("Couldn't drop certificate");
++ host_key = raw_key;
++ }
++
++ if (verify_host_key_dns(host, hostaddr, host_key, &flags))
++ goto done;
++
++ if (flags & DNS_VERIFY_FOUND) {
++
++ if (options.verify_host_key_dns == 1 &&
++ flags & DNS_VERIFY_MATCH &&
++ flags & DNS_VERIFY_SECURE) {
++ rc = 0;
++ } else if (flags & DNS_VERIFY_MATCH) {
++ matching_host_key_dns = 1;
++ } else {
++ warn_changed_key(host_key);
++ error("Update the SSHFP RR in DNS with the new "
++ "host key to get rid of this message.");
++ }
++ }
++
++done:
++ if (raw_key)
++ key_free(raw_key);
++ return rc;
++}
++
+ /* returns 0 if key verifies or -1 if key does NOT verify */
+ int
+ verify_host_key(char *host, struct sockaddr *hostaddr, Key *host_key)
+ {
+- int flags = 0;
+ char *fp;
+
+ fp = key_fingerprint(host_key, SSH_FP_MD5, SSH_FP_HEX);
+ debug("Server host key: %s %s", key_type(host_key), fp);
+ free(fp);
+
+- /* XXX certs are not yet supported for DNS */
+- if (!key_is_cert(host_key) && options.verify_host_key_dns &&
+- verify_host_key_dns(host, hostaddr, host_key, &flags) == 0) {
+- if (flags & DNS_VERIFY_FOUND) {
+-
+- if (options.verify_host_key_dns == 1 &&
+- flags & DNS_VERIFY_MATCH &&
+- flags & DNS_VERIFY_SECURE)
+- return 0;
+-
+- if (flags & DNS_VERIFY_MATCH) {
+- matching_host_key_dns = 1;
+- } else {
+- warn_changed_key(host_key);
+- error("Update the SSHFP RR in DNS with the new "
+- "host key to get rid of this message.");
+- }
+- }
+- }
++ if (check_host_key_sshfp(host, hostaddr, host_key) == 0)
++ return 0;
+
+ return check_host_key(host, hostaddr, options.port, host_key, RDRW,
+ options.user_hostfiles, options.num_user_hostfiles,
+--
+1.7.9.5
+
diff --git a/meta/recipes-connectivity/openssh/openssh_6.5p1.bb b/meta/recipes-connectivity/openssh/openssh_6.5p1.bb
index 230f38a..795e085 100644
--- a/meta/recipes-connectivity/openssh/openssh_6.5p1.bb
+++ b/meta/recipes-connectivity/openssh/openssh_6.5p1.bb
@@ -30,7 +30,8 @@ SRC_URI = "ftp://ftp.openbsd.org/pub/OpenBSD/OpenSSH/portable/openssh-${PV}.tar.
file://volatiles.99_sshd \
file://add-test-support-for-busybox.patch \
file://run-ptest \
- file://openssh-CVE-2014-2532.patch"
+ file://openssh-CVE-2014-2532.patch \
+ file://openssh-CVE-2014-2653.patch"
PAM_SRC_URI = "file://sshd"
--
1.7.9.5
^ permalink raw reply related [flat|nested] 3+ messages in thread