Описание
Deno's --deny-write check does not prevent permission bypass
Summary
Deno.FsFile.prototype.utime and Deno.FsFile.prototype.utimeSync are not limited by the permission model check --deny-write=./.
It's possible to change to change the access (atime) and modification (mtime) times on the file stream resource even when the file is opened with read only permission (and write: false) and file write operations are not allowed (the script is executed with --deny-write=./).
Similar APIs like Deno.utime and Deno.utimeSync require allow-write permission, however, when a file is opened, even with read only flags and deny-write permission, it's still possible to change the access (atime) and modification (mtime) times, and thus bypass the permission model.
PoC
Setup:
Output:
deno run --allow-read=./ --deny-write=./ poc_file.utime.ts 1
deno run --allow-read=./ --deny-write=./ poc_file.utime.ts 2
deno run --allow-read=./ --deny-write=./ poc_file.utime.ts 3
deno run --allow-read=./ --deny-write=./ poc_file.utime.ts 4
Impact
Permission model bypass
Ссылки
- https://github.com/denoland/deno/security/advisories/GHSA-vg2r-rmgp-cgqj
- https://nvd.nist.gov/vuln/detail/CVE-2025-61785
- https://github.com/denoland/deno/pull/30872
- https://github.com/denoland/deno/commit/992e998dfe436cdc9325232759af8be92f11739b
- https://github.com/denoland/deno/releases/tag/v2.2.15
- https://github.com/denoland/deno/releases/tag/v2.5.3
Пакеты
deno
< 2.5.3
2.5.3
Связанные уязвимости
Deno is a JavaScript, TypeScript, and WebAssembly runtime. In versions prior to 2.5.3 and 2.2.15, `Deno.FsFile.prototype.utime` and `Deno.FsFile.prototype.utimeSync` are not limited by the permission model check `--deny-write=./`. It's possible to change to change the access (`atime`) and modification (`mtime`) times on the file stream resource even when the file is opened with `read` only permission (and `write`: `false`) and file write operations are not allowed (the script is executed with `--deny-write=./`). Similar APIs like `Deno.utime` and `Deno.utimeSync` require `allow-write` permission, however, when a file is opened, even with read only flags and deny-write permission, it's still possible to change the access (`atime`) and modification (`mtime`) times, and thus bypass the permission model. Versions 2.5.3 and 2.2.15 fix the issue.