Multiple unspecified vulnerabilities in the browser engine in Mozilla Firefox before 39.0 allow remote attackers to cause a denial of service (memory corruption and application crash) or possibly execute arbitrary code via unknown vectors.

Mozilla Network Security Services (NSS) before 3.19, as used in Mozilla Firefox before 39.0, Firefox ESR 31.x before 31.8 and 38.x before 38.1, Thunderbird before 38.1, and other products, does not properly determine state transitions for the TLS state machine, which allows man-in-the-middle attackers to defeat cryptographic protection mechanisms by blocking messages, as demonstrated by removing a forward-secrecy property by blocking a ServerKeyExchange message, aka a "SMACK SKIP-TLS" issue.

Heap-based buffer overflow in the PCNET controller in QEMU allows remote attackers to execute arbitrary code by sending a packet with TXSTATUS_STARTPACKET set and then a crafted packet with TXSTATUS_DEVICEOWNS set.

QEMU does not properly restrict write access to the PCI config space for certain PCI pass-through devices, which might allow local x86 HVM guests to gain privileges, cause a denial of service (host crash), obtain sensitive information, or possibly have other unspecified impact via unknown vectors.

The TLS protocol 1.2 and earlier, when a DHE_EXPORT ciphersuite is enabled on a server but not on a client, does not properly convey a DHE_EXPORT choice, which allows man-in-the-middle attackers to conduct cipher-downgrade attacks by rewriting a ClientHello with DHE replaced by DHE_EXPORT and then rewriting a ServerHello with DHE_EXPORT replaced by DHE, aka the "Logjam" issue.

Use-after-free vulnerability in the SetBreaks function in Mozilla Firefox before 38.0, Firefox ESR 31.x before 31.7, and Thunderbird before 31.7 allows remote attackers to execute arbitrary code or cause a denial of service (heap memory corruption) via a document containing crafted text in conjunction with a Cascading Style Sheets (CSS) token sequence containing properties related to vertical text.

Multiple unspecified vulnerabilities in the browser engine in Mozilla Firefox before 38.0 allow remote attackers to cause a denial of service (memory corruption and application crash) or possibly execute arbitrary code via unknown vectors.

Multiple unspecified vulnerabilities in the browser engine in Mozilla Firefox before 38.0, Firefox ESR 31.x before 31.7, and Thunderbird before 31.7 allow remote attackers to cause a denial of service (memory corruption and application crash) or possibly execute arbitrary code via unknown vectors.

Buffer overflow in the XML parser in Mozilla Firefox before 38.0, Firefox ESR 31.x before 31.7, and Thunderbird before 31.7 allows remote attackers to execute arbitrary code by providing a large amount of compressed XML data, a related issue to CVE-2015-1283.

Heap-based buffer overflow in the SVGTextFrame class in Mozilla Firefox before 38.0, Firefox ESR 31.x before 31.7, and Thunderbird before 31.7 allows remote attackers to execute arbitrary code via crafted SVG graphics data in conjunction with a crafted Cascading Style Sheets (CSS) token sequence.