Type confusion

The fixes for XSA-422 Branch Type Confusion and XSA-434 Speculative Return Stack Overflow are not IRQ-safe. It was believed that the mitigations always operated in contexts with IRQs disabled. However, the original XSA-254 fix for Meltdown XPTI deliberately left interrupts enabled on two entry...

CVE-2022-42331

x86: speculative vulnerability in 32bit SYSCALL path Due to an oversight in the very original Spectre/Meltdown security work XSA-254, one entrypath performs its speculation-safety actions too late. In some configurations, there is an unprotected RET instruction which can be attacked with a variet...

CVE-2022-42331

x86: speculative vulnerability in 32bit SYSCALL path Due to an oversight in the very original Spectre/Meltdown security work XSA-254, one entrypath performs its speculation-safety actions too late. In some configurations, there is an unprotected RET instruction which can be attacked with a variet...

CVE-2022-42331

CVE-2022-42331 describes a Xen hypervisor SPECULATIVE execution vulnerability on the x86 32-bit SYSCALL path. Root cause: an oversight in the original Spectre/Meltdown work (XSA-254) leads to an entrypath performing its speculation-safety actions too late, leaving an unprotected RET instruction i...

x86: PV guest may crash Xen with XPTI

ISSUE DESCRIPTION The workaround for the Meltdown vulnerability XSA-254 failed to deal with an error code path connecting the INT 80 handling with general exception handling. This results in an unconditional write attempt of the value zero to an address near 2^64, in cases where a PV guest has no...

Fedora 26 : xen (2018-0746dac335)

update Xen page-table isolation XPTI mitigation and add Branch Target Injection BTI mitigation for XSA-254 DoS via non-preemptable L3/L4 pagetable freeing XSA-252 1549568 grant table v2 - v1 transition may crash Xen XSA-255 1549570 x86 PVH guest without LAPIC may DoS the host XSA-256 1549572 Note...

Fedora 27 : xen (2018-c553a586c8)

add Xen page-table isolation XPTI mitigation and Branch Target Injection BTI mitigation for XSA-254 DoS via non-preemptable L3/L4 pagetable freeing XSA-252 1549568 grant table v2 - v1 transition may crash Xen XSA-255 1549570 x86 PVH guest without LAPIC may DoS the host XSA-256 1549572 Note that...

Xen Multiple Vulnerabilities (Spectre) (Meltdown) (XSA-254)

According to its self-reported version number, the Xen hypervisor installed on the remote host is affected by multiple vulnerabilities. Note that Nessus has checked the changeset versions based on the xen.git change log. Nessus did not check guest hardware configurations or if patches were applie...