Executive Summary
Informations | |||
---|---|---|---|
Name | CVE-2021-29474 | First vendor Publication | 2021-04-26 |
Vendor | Cve | Last vendor Modification | 2022-10-24 |
Security-Database Scoring CVSS v3
Cvss vector : CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:C/C:L/I:N/A:N | |||
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Overall CVSS Score | 5.8 | ||
Base Score | 5.8 | Environmental Score | 5.8 |
impact SubScore | 1.4 | Temporal Score | 5.8 |
Exploitabality Sub Score | 3.9 | ||
Attack Vector | Network | Attack Complexity | Low |
Privileges Required | None | User Interaction | None |
Scope | Changed | Confidentiality Impact | Low |
Integrity Impact | None | Availability Impact | None |
Calculate full CVSS 3.0 Vectors scores |
Security-Database Scoring CVSS v2
Cvss vector : (AV:N/AC:L/Au:N/C:P/I:N/A:N) | |||
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Cvss Base Score | 5 | Attack Range | Network |
Cvss Impact Score | 2.9 | Attack Complexity | Low |
Cvss Expoit Score | 10 | Authentication | None Required |
Calculate full CVSS 2.0 Vectors scores |
Detail
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. |
Original Source
Url : http://cve.mitre.org/cgi-bin/cvename.cgi?name=CVE-2021-29474 |
CWE : Common Weakness Enumeration
% | Id | Name |
---|---|---|
100 % | CWE-22 | Improper Limitation of a Pathname to a Restricted Directory ('Path Traversal') (CWE/SANS Top 25) |
CPE : Common Platform Enumeration
Type | Description | Count |
---|---|---|
Application | 1 |
Sources (Detail)
Source | Url |
---|---|
CONFIRM | https://github.com/hedgedoc/hedgedoc/security/advisories/GHSA-p528-555r-pf87 |
Alert History
Date | Informations |
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2022-10-25 00:27:39 |
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2021-05-08 00:22:49 |
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2021-04-27 17:22:52 |
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2021-04-27 05:22:49 |
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