{"cve":"CVE-2026-1979","nvd":{"published":"2026-02-06T05:16:12.667","modified":"2026-06-17T10:16:49.260","status":"Analyzed","description":"A flaw has been found in mruby up to 3.4.0. This affects the function mrb_vm_exec of the file src/vm.c of the component JMPNOT-to-JMPIF Optimization. Executing a manipulation can lead to use after free. The attack needs to be launched locally. The exploit has been published and may be used. This patch is called e50f15c1c6e131fa7934355eb02b8173b13df415. It is advisable to implement a patch to correct this issue.","cvss_v4":{"vector":"CVSS:4.0/AV:L/AC:L/AT:N/PR:L/UI:N/VC:L/VI:L/VA:L/SC:N/SI:N/SA:N/E:P","score":1.9},"cvss_v3":{"version":"3.1","vector":"CVSS:3.1/AV:L/AC:L/PR:L/UI:N/S:U/C:N/I:N/A:H","score":5.5},"cwes":["CWE-119","CWE-416"],"references":["https://github.com/mruby/mruby/","https://github.com/mruby/mruby/issues/6701","https://github.com/mruby/mruby/issues/6701#issue-3802609843","https://github.com/sysfce2/mruby/commit/e50f15c1c6e131fa7934355eb02b8173b13df415","https://vuldb.com/?ctiid.344501"],"products":["mruby:mruby"],"source":"nvd","synced_at":"2026-10-19T22:22:27.261130201+00:00"},"epss":{"cve":"CVE-2026-1979","score":0.00179,"percentile":0.07502,"date":"2026-10-31"},"kev":null,"osv":[],"attribution":["This product uses the NVD API but is not endorsed or certified by the NVD.","EPSS scores: FIRST Exploit Prediction Scoring System, https://www.first.org/epss","Known exploited vulnerabilities: CISA Known Exploited Vulnerabilities Catalog, https://www.cisa.gov/known-exploited-vulnerabilities-catalog","Package advisories: OSV (https://osv.dev), from the GitHub Advisory Database, PyPA, Go, RustSec and other ecosystem databases, under CC-BY 4.0 or CC0","CVE records: the CVE Program's CVE List (https://www.cve.org), under its terms of use (https://www.cve.org/Legal/TermsOfUse). CVE is a registered trademark of The MITRE Corporation; this product is not affiliated with the CVE Program."]}