Fragnesia and friends: When page cache vulnerabilities keep coming back

Multiple Linux kernel vulnerabilities exploiting similar page cache manipulation techniques emerged within two weeks in 2026, including Copy-Fail, Dirty Frag, Fragnesia, and DirtyDecrypt. Red Hat OpenShift’s layered security approach combining SELinux enforcement and security context constraints successfully prevented host system compromise even when individual kernel vulnerabilities existed, demonstrating the value of defense-in-depth strategies against real-world kernel flaws.