CVE-2019-19602 — fpregs_state_valid in arch/x86/include/asm/fpu/internal

fpregs_state_valid in arch/x86/include/asm/fpu/internal.h in the Linux kernel before 5.4.2, when GCC 9 is used, allows context-dependent attackers to cause a denial of service (memory corruption) or possibly have unspecified other impact because of incorrect fpu_fpregs_owner_ctx

01What is this vulnerability?

fpregs_state_valid in arch/x86/include/asm/fpu/internal.h in the Linux kernel before 5.4.2, when GCC 9 is used, allows context-dependent attackers to cause a denial of service (memory corruption) or possibly have unspecified other impact because of incorrect fpu_fpregs_owner_ctx caching, as demonstrated by mishandling of signal-based non-cooperative preemption in Go 1.14 prereleases on amd64, aka…

02Affected products

Vendor	Product	Versions
n	a / n/a	n/a

03Active exploitation status

Not currently listed on the CISA Known Exploited Vulnerabilities (KEV) catalog. EPSS is the best forward-looking signal — see the EPSS row above.

04Recommended remediation

• Patch to a fixed version listed in the vendor advisory (see references below).
• Mitigate with WAF rules, network egress filters, or feature flags where the patch is not yet available.
• Hunt historical logs for exploitation indicators — see Detection signatures below.

05Technical details

For the full vendor write-up, exploit chains, and reference implementations, see the references list in section 09.

06Detection signatures

Ask SARA in chat to draft a starting detection for this CVE in your stack of choice.

07Related CVEs

No directly-cited follow-up CVEs in the KB record for this advisory. The references list in section 09 carries the vendor cross-references.

08Timeline

• Published: 2019-12-05T13:21:28.000Z
• Last modified: 2024-08-05T02:25:11.436Z

09References

• git.kernel.org — https://git.kernel.org/cgit/linux/kernel/git/torvalds/linux.git/commit/?id=59c4b…
• github.com — https://github.com/torvalds/linux/commit/59c4bd853abcea95eccc167a7d7fd5f1a5f47b9…
• cdn.kernel.org — https://cdn.kernel.org/pub/linux/kernel/v5.x/ChangeLog-5.4.2
• github.com — https://github.com/golang/go/issues/35777#issuecomment-561935388
• bugzilla.kernel.org — https://bugzilla.kernel.org/show_bug.cgi?id=205663
• security.netapp.com — https://security.netapp.com/advisory/ntap-20200103-0001/
• usn.ubuntu.com — https://usn.ubuntu.com/4284-1/