csirt@kutim:~/threat-intel/cve/CVE-2021-29474

Katalog CVE

CVSS 5.8 · Medium EPSS 1,6%

Kerentanan Improper Input Validation pada hedgedoc. Skor CVSS 3.1 5.8 (Medium) menurut NVD.

Deskripsi (NVD)

HedgeDoc (formerly known as CodiMD) is an open-source collaborative markdown editor. An attacker can read arbitrary `.md` files from the server's filesystem due to an improper input validation, which results in the ability to perform a relative path traversal. To verify if you are affected, you can try to open the following URL: `http://localhost:3000/..%2F..%2FREADME#` (replace `http://localhost:3000` with your instance's base-URL e.g. `https://demo.hedgedoc.org/..%2F..%2FREADME#`). If you see a README page being rendered, you run an affected version. The attack works due the fact that the internal router passes the url-encoded alias to the `noteController.showNote`-function. This function passes the input directly to findNote() utility function, that will pass it on the the parseNoteId()-function, that tries to make sense out of the noteId/alias and check if a note already exists and if so, if a corresponding file on disk was updated. If no note exists the note creation-function is called, which pass this unvalidated alias, with a `.md` appended, into a path.join()-function which is read from the filesystem in the follow up routine and provides the pre-filled content of the new note. This allows an attacker to not only read arbitrary `.md` files from the filesystem, but also observes changes to them. The usefulness of this attack can be considered limited, since mainly markdown files are use the file-ending `.md` and all markdown files contained in the hedgedoc project, like the README, are public anyway. If other protections such as a chroot or container or proper file permissions are in place, this attack's usefulness is rather limited. On a reverse-proxy level one can force a URL-decode, which will prevent this attack because the router will not accept such a path.

Rincian

Terbit di NVD
26 April 2021
Terakhir diubah
17 Juni 2026
Status NVD
Modified
CVSS 3.1
5.8 (Medium), sumber NVD
CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:C/C:L/I:N/A:N · uraikan di kalkulator
Jenis kelemahan (CWE)
CWE-20: Improper Input Validation
CWE-22: Improper Limitation of a Pathname to a Restricted Directory ('Path Traversal')
EPSS (30 hari)
1,6% peluang dieksploitasi; lebih tinggi dari 75,1% CVE lain

Produk dan versi terdampak

VendorProdukVersi terdampak
hedgedoc hedgedoc Semua versi sebelum 1.8.0

> Data dari konfigurasi CPE di NVD.

Referensi dan perbaikan

Sumber: NVD · CVE.org · EPSS. Halaman ini disusun otomatis dari data tersebut; pembaruan terakhir 5 Okt 2026, 20:10 WITA. Kalau sistem di Perangkat Daerah memakai produk ini dan butuh bantuan, laporkan lewat kanal pelaporan.