CVE-2017-18261 — The arch_timer_reg_read_stable macro in arch/arm64/include/asm/arch_timer

The arch_timer_reg_read_stable macro in arch/arm64/include/asm/arch_timer.h in the Linux kernel before 4.13 allows local users to cause a denial of service (infinite recursion) by writing to a file under /sys/kernel/debug in certain circumstances, as demonstrated by a scenario in

01What is this vulnerability?

The arch_timer_reg_read_stable macro in arch/arm64/include/asm/arch_timer.h in the Linux kernel before 4.13 allows local users to cause a denial of service (infinite recursion) by writing to a file under /sys/kernel/debug in certain circumstances, as demonstrated by a scenario involving debugfs, ftrace, PREEMPT_TRACER, and FUNCTION_GRAPH_TRACER.

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: 2018-04-19T08:00:00.000Z
• Last modified: 2024-08-05T21:13:49.293Z

09References

• git.kernel.org — http://git.kernel.org/cgit/linux/kernel/git/torvalds/linux.git/commit/?id=adb4f1…
• github.com — https://github.com/torvalds/linux/commit/adb4f11e0a8f4e29900adb2b7af28b6bbd5c1fa…