CVE-2024-26603

medium

Published 2024-11-12 · Modified 2024-06-05

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CVSS v3

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CVSS v4 NEW

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not yet in upstream

VIR risk

5.5

Description

In the Linux kernel, the following vulnerability has been resolved: x86/fpu: Stop relying on userspace for info to fault in xsave buffer Before this change, the expected size of the user space buffer was taken from fx_sw->xstate_size. fx_sw->xstate_size can be changed from user-space, so it is possible construct a sigreturn frame where: * fx_sw->xstate_size is smaller than the size required by valid bits in fx_sw->xfeatures. * user-space unmaps parts of the sigrame fpu buffer so that not all of the buffer required by xrstor is accessible. In this case, xrstor tries to restore and accesses the unmapped area which results in a fault. But fault_in_readable succeeds because buf + fx_sw->xstate_size is within the still mapped area, so it goes back and tries xrstor again. It will spin in this loop forever. Instead, fault in the maximum size which can be touched by XRSTOR (taken from fpstate->user_size). [ dhansen: tweak subject / changelog ]

Predictions

Exploit likelihood

20%

Patch ETA

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Heuristic predictions, AS-IS, for prioritization only.

Mitigations

No mitigations published for this CVE yet.

The vendor-content worker queues fetches as references arrive (check back in a few minutes). Or — if you've already worked around this in production — publish your fix to the community-verified tier.

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OS impact

OS	Version	Status	Fixed in
rhel	9	fixed
rocky	8	fixed
sles		affected
debian	bookworm	fixed	`6.1.82-1`
debian	bullseye	fixed	`0`
debian	forky	fixed	`6.7.7-1`
debian	sid	fixed	`6.7.7-1`
debian	trixie	fixed	`6.7.7-1`
almalinux	8	fixed	`kernel-abi-stablelists-4.18.0-553.5.1.el8_10.noarch.rpm`

References

Community-verified mitigations for this CVE will appear above when contributors publish them.

Verify integrity in audit chain (admin only). AS-IS.