CVE-2023-1998 — The Linux kernel allows userspace processes to enable mitigations by calling prc

The Linux kernel allows userspace processes to enable mitigations by calling prctl with PR_SET_SPECULATION_CTRL which disables the speculation feature as well as by using seccomp. We had noticed that on VMs of at least one major cloud provider, the kernel still left the victim pr

01What is this vulnerability?

The Linux kernel allows userspace processes to enable mitigations by calling prctl with PR_SET_SPECULATION_CTRL which disables the speculation feature as well as by using seccomp. We had noticed that on VMs of at least one major cloud provider, the kernel still left the victim process exposed to attacks in some cases even after enabling the spectre-BTI mitigation with prctl. The same behavior can…

02Affected products

Vendor	Product	Versions
Linux	Linux Kernel	0

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: 2023-04-21T14:51:52.907Z
• Last modified: 2025-02-13T16:39:44.383Z

09References

• github.com — https://github.com/google/security-research/security/advisories/GHSA-mj4w-6495-6…
• github.com — https://github.com/torvalds/linux/commit/6921ed9049bc7457f66c1596c5b78aec0dae4a9…
• kernel.dance — https://kernel.dance/#6921ed9049bc7457f66c1596c5b78aec0dae4a9d
• lists.debian.org — https://lists.debian.org/debian-lts-announce/2023/05/msg00005.html
• lists.debian.org — https://lists.debian.org/debian-lts-announce/2023/05/msg00006.html