CVE-2026-102916: medium-severity vulnerability in illumos-gate
Reachable assertion in illumos bhyve REP string instruction emulation allows guest to panic host
Published
13Vexday Risk Score
No sign of exploitation. No public exploitation artifact known so far.
ssvc Trackcvss 6.8epss 0.1%
exploitation probability
0.1%top 98% of all CVEs
observed exploitation
nono source reports it
A reachable assertion in the illumos bhyve instruction emulator allows a guest to panic the host. When emulating a REP-prefixed MOVS or STOS instruction that accesses guest MMIO, vie_emulate_movs() and vie_emulate_stos() in usr/src/uts/intel/io/vmm/vmm_instruction_emul.c do not clear the VIES_REPEAT status flag on the final iteration. For MMIO regions emulated in the kernel (the local APIC, I/O APIC and HPET), the stale flag causes a VERIFY assertion in vie_advance_pc() to fail, and the host panics. A privileged user within a guest VM can issue a REP MOVS or REP STOS instruction against the local APIC page to cause a denial of service of the host and every other guest running on it. The flaw has existed since 2020 (illumos-gate commit e0c0d44e), and affects any illumos distribution prior to illumos-gate commit 696ecf8d.
CVSS:4.0/AV:L/AC:L/AT:N/PR:L/UI:N/VC:N/VI:N/VA:H/SC:N/SI:N/SA:H/E:P/AU:Y/R:A/V:C
Related CVEs — illumos-gate
In the same product, most dangerous first.
CVE-2026-15422CRITICALSCTP needs to better-check INIT ACK chunk parametersEPSS 0.9%CVE-2026-104115MEDIUMStack buffer overflow in illumos reparsed nfs-basic plugin allows local users to crash the daemonEPSS 0.1%CVE-2026-104114MEDIUMNULL pointer dereference in illumos nwamd door handler allows local users to crash the daemonEPSS 0.1%CVE-2026-104112MEDIUMMissing release of passed file descriptors in illumos nscd allows local users to exhaust kernel memoryEPSS 0.1%CVE-2026-104113MEDIUMDouble free in OmniOS and SmartOS ipmgmtd allows local users to crash the daemonEPSS 0.1%CVE-2026-15449MEDIUMTOCTOU double copyin in illumos dld ioctl handling causes kernel heap corruptionEPSS 0.1%
References
https://github.com/illumos/illumos-gate/commit/696ecf8debceed9dc33937d8c8e111e4aeebfdaehttps://illumos.org/issues/18491https://illumos.topicbox.com/groups/developer/T697a32b688807e56/cve-2026-102916-18491-bhyve-rep-prefix-instr-emulation-fumbles-flagshttp://www.openwall.com/lists/oss-security/2026/10/09/19