{"id":"CVE-2026-49983","summary":"Deno: process.loadEnvFile() bypasses env permission checks and mutates process.env with only read access","details":"Deno is a JavaScript, TypeScript, and WebAssembly runtime. Prior to 2.8.1, environment access is gated by the env permission. You can deny it with --deny-env, or restrict it to a specific allowlist with --allow-env=FOO,BAR. The expectation is that a program running without env permission cannot change process.env. process.loadEnvFile() (the Node-compatible API for loading variables from a .env file) does not honor this. It only checks that the program has read permission for the dotenv file, then writes every key in that file into the process environment — even when env access is denied. In effect, --allow-read plus a writable or attacker-controlled .env file is enough to defeat --deny-env. This vulnerability is fixed in 2.8.1.","aliases":["GHSA-4c8g-jvcx-v4hv"],"modified":"2026-07-15T01:49:04.962061279Z","published":"2026-06-23T17:16:17.026Z","database_specific":{"osv_generated_from":"https://github.com/CVEProject/cvelistV5/tree/main/cves/2026/49xxx/CVE-2026-49983.json","cna_assigner":"GitHub_M","cwe_ids":["CWE-863"]},"references":[{"type":"ADVISORY","url":"https://github.com/CVEProject/cvelistV5/tree/main/cves/2026/49xxx/CVE-2026-49983.json"},{"type":"ADVISORY","url":"https://github.com/denoland/deno/security/advisories/GHSA-4c8g-jvcx-v4hv"},{"type":"ADVISORY","url":"https://nvd.nist.gov/vuln/detail/CVE-2026-49983"}],"affected":[{"ranges":[{"type":"GIT","repo":"https://github.com/denoland/deno","events":[{"introduced":"61574bb9c9c255d5c661add6c7464af30475c197"},{"fixed":"3e2030bc01776ce6b4ca355b1e78c4cb98c82dca"}],"database_specific":{"source":["AFFECTED_FIELD","CPE_RANGE"],"cpe":"cpe:2.3:a:deno:deno:*:*:*:*:*:*:*:*","extracted_events":[{"introduced":"0"},{"fixed":"2.8.1"},{"introduced":"2.3.0"}]}}],"versions":["v2.8.0","v2.7.14","v2.7.13","v2.7.12","v2.7.11","v2.7.10","v2.7.9","v2.7.8","v2.7.7","v2.7.6","v2.7.5","v2.7.4","v2.7.3","v2.7.2","v2.7.1","v2.7.0","v2.6.10","v2.6.9","v2.6.8","v2.6.7","v2.5.6","v2.6.6","v2.6.5","v2.6.4","v2.6.3","v2.6.2","v2.6.0","v2.3.0","v2.5.5","v2.5.4","v2.5.3","v2.5.2","v2.5.1","v2.5.0","v2.4.5","v2.4.4","v2.4.3","v2.4.2","v2.4.1","v2.4.0","v2.3.7","v2.3.6","v2.3.5","v2.3.4","v2.3.3","v2.3.2","v2.3.1"],"database_specific":{"source":"https://storage.googleapis.com/cve-osv-conversion/osv-output/CVE-2026-49983.json"}}],"schema_version":"1.7.5","severity":[{"type":"CVSS_V3","score":"CVSS:3.1/AV:L/AC:L/PR:L/UI:N/S:C/C:L/I:L/A:N"}]}