CVE-2015-2877

Description

Kernel Samepage Merging (KSM) in the Linux kernel 2.6.32 through 4.x does not prevent use of a write-timing side channel, which allows guest OS users to defeat the ASLR protection mechanism on other guest OS instances via a Cross-VM ASL INtrospection (CAIN) attack. NOTE: the vendor states "Basically if you care about this attack vector, disable deduplication." Share-until-written approaches for memory conservation among mutually untrusting tenants are inherently detectable for information disclosure, and can be classified as potentially misunderstood behaviors rather than vulnerabilities

Weakness classification

• CWE-200: Exposure of Sensitive Information to an Unauthorized Actor

Primary references

• cret@cert.org — Technical Description, Third Party Advisory
• cret@cert.org — Third Party Advisory, US Government Resource
• cret@cert.org — Third Party Advisory, VDB Entry
• cret@cert.org — Issue Tracking, Third Party Advisory
• cret@cert.org — Third Party Advisory, US Government Resource
• cret@cert.org — Third Party Advisory, US Government Resource
• cret@cert.org — Technical Description, Third Party Advisory
• af854a3a-2127-422b-91ae-364da2661108 — Technical Description, Third Party Advisory
• af854a3a-2127-422b-91ae-364da2661108 — Third Party Advisory, US Government Resource
• af854a3a-2127-422b-91ae-364da2661108 — Third Party Advisory, VDB Entry
• af854a3a-2127-422b-91ae-364da2661108 — Issue Tracking, Third Party Advisory
• af854a3a-2127-422b-91ae-364da2661108 — Third Party Advisory, US Government Resource