CVE-2015-2877: Kernel Samepage Merging (KSM) in the Linux kernel 2.6.32 through 4.x does not prevent use of a write-timing...

Security readout for executives and security teams

This issue concerns memory deduplication on Linux virtualization hosts. When Kernel Samepage Merging is enabled for untrusted guests, timing differences may let one guest infer ASLR-related information from another guest. It is not reported as actively exploited and is partly characterized by the vendor as an inherent risk of deduplication. Most relevant to multi-tenant virtualization environments running affected Linux kernels with KSM or memory deduplication enabled across mutually untrusted guests. Single-tenant hosts, systems without KSM, or environments without untrusted guest co-residency appear less exposed based on the provided sources. Treat this as a targeted cloud or virtualization isolation risk, not an internet-wide emergency. Prioritize review if the organization operates multi-tenant Linux virtualization with memory deduplication enabled. Disabling deduplication may trade memory efficiency for stronger tenant isolation. Mitigation focus: Disable KSM or cross-tenant memory deduplication where guests are mutually untrusted.; Check current Linux vendor guidance for supported kernel-specific recommendations.; Avoid co-locating sensitive workloads with untrusted tenants on deduplicating hosts..

Prepared

Jun 13, 2026, 06:02 UTC (UTC+00:00)

Generated from the cited source records. This long-tail analysis has not been individually reviewed by a named human.