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TI-2021-21003 Aliases CVE-2021-46023GHSA-4g9q-c75g-jq7q

An Untrusted Pointer Dereference was discovered in function mrb_vm_exec in mruby before…

Priority MEDIUM 40CWE-119Published · Updated

Key facts

Attack vector
Network
Privileges required
None
User interaction
None
Attack complexity
Low
Impact type
Denial of service
Confidentiality · integrity · availability
None · None · High
Fix status
No fix listed

Attack profile from CVSS 3.1 · CISA ADP. Fix status from CNA. Impact type from CWE-119 and the CVSS impact.

Summary

An Untrusted Pointer Dereference was discovered in function mrb_vm_exec in mruby before 3.1.0-rc. The vulnerability causes a segmentation fault and application crash.

Why it matters now

Exploitation None reported CISA SSVC · not in CISA KEV
EPSS 0.00776 56th percentileScored 2026-11-07
Public exploit Yes 1 exploit referenceTagged by NVD
Fix No fix listed No fixed version in the sources yet

SSVC decision points

CISA ADP · SSVC 2.0.3

Exploitation
None
Automatable
Yes
Technical impact
Partial

The decision (Track, Attend, Act) also depends on your mission and well-being impact; see CISA's SSVC guide.

Affected products

VendorProductAffected versionsFixed inStatusSource
——all versions—No fix listedCNA
  • — Vendor— Affected all versions Fixed in — No fix listed CNA

CPE configurations NVD · 1

CPEVersionsRoleVendor
cpe:2.3:a:mruby:mruby:*:*:*:*:*:ruby:*:*before 3.1.0Vulnerablemruby
  • cpe:2.3:a:mruby:mruby:*:*:*:*:*:ruby:*:* Versions before 3.1.0 Vulnerable ·mruby

Remediation

No fixed version listed by the sources yet.

Timeline

  1. 2026-10-02 Threatist record created from CVE-2021-46023
  2. 2026-10-03 Alias added: GHSA-4g9q-c75g-jq7q

References

Exploit 1

  • TI-2022-00033 Heap-based Buffer Overflow in mruby/mruby CVSS 3.1CRITICAL 9.8
  • TI-2026-01636 mruby JMPNOT-to-JMPIF Optimization vm.c mrb_vm_exec use after free CVSS 4.0MEDIUM 4.8
  • TI-2025-11794 mruby array.c ary_fill_exec out-of-bounds write CVSS 4.0MEDIUM 4.8
  • TI-2025-06567 mruby nregs codegen.c scope_new heap-based overflow CVSS 4.0MEDIUM 4.8
  • TI-2018-07224 In versions of mruby up to and including 1.4.0, an integer overflow exists in… CVSS 3.1CRITICAL 9.8
  • TI-2022-01100 Use-After-Free in str_escape in mruby/mruby in mruby/mruby CVSS 3.1CRITICAL 9.8
See all 41 →

Sources

This product uses the NVD API but is not endorsed or certified by the NVD. Sources and licences