Security researchers disclose a new Linux local privilege escalation vulnerability, codenamed “Fragnesia,” tracked as CVE-2026-46300. Multiple outlets describe it as part of the same vulnerability family as the previously public “Dirty Frag” issues, with similar memory and page-cache handling. The flaw involves kernel behavior linked to the XFRM subsystem and the xfrm-ESP logic, and it enables a local attacker to escalate privileges to root by corrupting or writing to kernel memory related to the page cache of read-only files.
Reports indicate public proof-of-concept exploit code is already available. A short kernel fix is described as involving a patch to the Linux kernel networking buffer code (skbuff.c), but outlets note that the patch has not yet been mainlined or included in mainline kernel releases at the time of reporting. Disclosures also characterize the bug as the third related kernel LPE issue identified within a roughly two-week period.
Some reporting adds that Fragnesia may have been unintentionally introduced or activated by changes made to address Dirty Frag, according to attribution from researchers involved with the earlier vulnerability.
