--- cve: "CVE-2026-41316" severity: "HIGH" cvss: 8.1 epss: "1.1%" vendor: "Ruby" kev: false exploited: false published: "2026-04-24 03:16:11" tags: [cve, security, high] source: tsecurity.de CVE-Dossier exported: "2026-09-08T16:55:42+02:00" --- # CVE-2026-41316 > 8.1 HIGH · 🧪 PoC ## Beschreibung ERB is a templating system for Ruby. Ruby 2.7.0 (before ERB 2.2.0 was published on rubygems.org) introduced an `@_init` instance variable guard in `ERB#result` and `ERB#run` to prevent code execution when an ERB object is reconstructed via `Marshal.load` (deserialization). However, three other public methods that also evaluate `@src` via `eval()` were not given the same guard: `ERB#def_method`, `ERB#def_module`, and `ERB#def_class`. An attacker who can trigger `Marshal.load` on untrusted data in a Ruby application that has `erb` loaded can use `ERB#def_module` (zero-arg, default parameters) as a code execution sink, bypassing the `@_init` protection entirely. ERB 4.0.3.1, 4.0.4.1, 6.0.1.1, and 6.0.4 patch the issue. ## CVSS-Vektor ``` CVSS:3.1/AV:N/AC:H/PR:N/UI:N/S:U/C:H/I:H/A:H ``` | Metrik | Wert | Bewertung | |---|---|---| | AV Angriffsvektor | Netzwerk | bad | | AC Komplexität | Hoch | good | | PR Privilegien | Keine | bad | | UI Interaktion | Keine | bad | | S Scope | Unverändert | good | | C Vertraulichkeit | Hoch | bad | | I Integrität | Hoch | bad | | A Verfügbarkeit | Hoch | bad | ## Patch verfügbar (OSV) - b6be29fd0e0f5089447d2f8d18140ae78258621d (Commit) - 93450765b5319cfb552a3d9719df137e8fbb75e9 (Commit) ## Referenzen - - - - - - - - - - - - --- _Exportiert aus dem [tsecurity.de CVE-Dossier](https://tsecurity.de/cve?cve=CVE-2026-41316) · Datenquellen: EUVD (ENISA), NVD, OSV, CISA KEV, FIRST EPSS, Exploit-DB, BSI BITS_