CVE-2017-9527 — The mark_context_stack function in gc

The mark_context_stack function in gc.c in mruby through 1.2.0 allows attackers to cause a denial of service (heap-based use-after-free and application crash) or possibly have unspecified other impact via a crafted .rb file.

01What is this vulnerability?

The mark_context_stack function in gc.c in mruby through 1.2.0 allows attackers to cause a denial of service (heap-based use-after-free and application crash) or possibly have unspecified other impact via a crafted .rb file.

02Affected products

No structured affected-product list available — see references below for vendor advisories.

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: 2017-06-11T17:29:00.160
• Last modified: 2026-05-13T00:24:29.033

09References

• github.com — https://github.com/mruby/mruby/commit/5c114c91d4ff31859fcd84cf8bf349b737b90d99
• github.com — https://github.com/mruby/mruby/issues/3486
• lists.debian.org — https://lists.debian.org/debian-lts-announce/2022/05/msg00006.html
• github.com — https://github.com/mruby/mruby/commit/5c114c91d4ff31859fcd84cf8bf349b737b90d99
• github.com — https://github.com/mruby/mruby/issues/3486
• lists.debian.org — https://lists.debian.org/debian-lts-announce/2022/05/msg00006.html