Ubuntu Security Notice USN-3087-2
23rd September, 2016
openssl regression
A security issue affects these releases of Ubuntu and its
derivatives:
- Ubuntu 16.04 LTS
- Ubuntu 14.04 LTS
- Ubuntu 12.04 LTS
Summary
USN-3087-1 introduced a regression in OpenSSL.
Software description
- openssl
– Secure Socket Layer (SSL) cryptographic library and tools
Details
USN-3087-1 fixed vulnerabilities in OpenSSL. The fix for CVE-2016-2182 was
incomplete and caused a regression when parsing certificates. This update
fixes the problem.
We apologize for the inconvenience.
Original advisory details:
Shi Lei discovered that OpenSSL incorrectly handled the OCSP Status Request
extension. A remote attacker could possibly use this issue to cause memory
consumption, resulting in a denial of service. (CVE-2016-6304)
Guido Vranken discovered that OpenSSL used undefined behaviour when
performing pointer arithmetic. A remote attacker could possibly use this
issue to cause OpenSSL to crash, resulting in a denial of service. This
issue has only been addressed in Ubuntu 16.04 LTS in this update.
(CVE-2016-2177)
César Pereida, Billy Brumley, and Yuval Yarom discovered that OpenSSL
did not properly use constant-time operations when performing DSA signing.
A remote attacker could possibly use this issue to perform a cache-timing
attack and recover private DSA keys. (CVE-2016-2178)
Quan Luo discovered that OpenSSL did not properly restrict the lifetime
of queue entries in the DTLS implementation. A remote attacker could
possibly use this issue to consume memory, resulting in a denial of
service. (CVE-2016-2179)
Shi Lei discovered that OpenSSL incorrectly handled memory in the
TS_OBJ_print_bio() function. A remote attacker could possibly use this
issue to cause a denial of service. (CVE-2016-2180)
It was discovered that the OpenSSL incorrectly handled the DTLS anti-replay
feature. A remote attacker could possibly use this issue to cause a denial
of service. (CVE-2016-2181)
Shi Lei discovered that OpenSSL incorrectly validated division results. A
remote attacker could possibly use this issue to cause a denial of service.
(CVE-2016-2182)
Karthik Bhargavan and Gaetan Leurent discovered that the DES and Triple DES
ciphers were vulnerable to birthday attacks. A remote attacker could
possibly use this flaw to obtain clear text data from long encrypted
sessions. This update moves DES from the HIGH cipher list to MEDIUM.
(CVE-2016-2183)
Shi Lei discovered that OpenSSL incorrectly handled certain ticket lengths.
A remote attacker could use this issue to cause a denial of service.
(CVE-2016-6302)
Shi Lei discovered that OpenSSL incorrectly handled memory in the
MDC2_Update() function. A remote attacker could possibly use this issue to
cause a denial of service. (CVE-2016-6303)
Shi Lei discovered that OpenSSL incorrectly performed certain message
length checks. A remote attacker could possibly use this issue to cause a
denial of service. (CVE-2016-6306)
Update instructions
The problem can be corrected by updating your system to the following
package version:
- Ubuntu 16.04 LTS:
-
libssl1.0.0
1.0.2g-1ubuntu4.5
- Ubuntu 14.04 LTS:
-
libssl1.0.0
1.0.1f-1ubuntu2.21
- Ubuntu 12.04 LTS:
-
libssl1.0.0
1.0.1-4ubuntu5.38
To update your system, please follow these instructions:
https://wiki.ubuntu.com/Security/Upgrades.
After a standard system update you need to reboot your computer to make
all the necessary changes.