5 Medium
CVSS2
Access Vector
NETWORK
Access Complexity
LOW
Authentication
NONE
Confidentiality Impact
NONE
Integrity Impact
NONE
Availability Impact
PARTIAL
AV:N/AC:L/Au:N/C:N/I:N/A:P
0.944 High
EPSS
Percentile
99.0%
There is a carry propagating bug in the x86_64 Montgomery squaring
procedure. No EC algorithms are affected. Analysis suggests that attacks against RSA
and DSA as a result of this defect would be very difficult to perform and are
not believed likely. Attacks against DH are considered just feasible
(although very difficult) because most of the work necessary to deduce information
about a private key may be performed offline. The amount of resources
required for such an attack would be very significant and likely only
accessible to a limited number of attackers. An attacker would
additionally need online access to an unpatched system using the target
private key in a scenario with persistent DH parameters and a private
key that is shared between multiple clients. For example this can occur
by default in OpenSSL DHE based SSL/TLS ciphersuites.[1]
The signature verification routines will crash with a NULL pointer
dereference if presented with an ASN.1 signature using the RSA PSS algorithm and
absent mask generation function parameter. Since these routines are used to
verify certificate signature algorithms this can be used to crash any
certificate verification operation and exploited in a DoS attack. Any application
which performs certificate verification is vulnerable including OpenSSL
clients and servers which enable client authentication.[2]
When presented with a malformed X509_ATTRIBUTE structure OpenSSL will
leak memory. This structure is used by the PKCS#7 and CMS routines so any
application which reads PKCS#7 or CMS data from untrusted sources is
affected. SSL/TLS is not affected.[3]
If PSK identity hints are received by a multi-threaded client then
the values are wrongly updated in the parent SSL_CTX structure. This can
result in a race condition potentially leading to a double free of the
identify hint data.[4]
If a client receives a ServerKeyExchange for an anonymous DH ciphersuite
with the value of p set to 0 then a seg fault can occur leading to a possible
denial of service attack.[5]
web.nvd.nist.gov/view/vuln/detail?vulnId=CVE-2015-1794
web.nvd.nist.gov/view/vuln/detail?vulnId=CVE-2015-3193
web.nvd.nist.gov/view/vuln/detail?vulnId=CVE-2015-3194
web.nvd.nist.gov/view/vuln/detail?vulnId=CVE-2015-3195
web.nvd.nist.gov/view/vuln/detail?vulnId=CVE-2015-3196
www.openssl.org/news/secadv/20151203.txt