CVE-2015-2877: Linux Kernel

Low severity, CVSS 3.3. EPSS: 0.9% chance of exploitation in the next 30 days.

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

Affected products

• Linux Linux Kernel: from 2.6.32, up to and including 4.20.15
• Red Hat Enterprise Linux: version 4.0 only; version 5.0 only; version 6.0 only; version 7.0 only

Published 2017-03-03. Last modified 2026-06-17.