CVE-2023-28631
Attacker controlled data in AST nodes is not validated in comrak
- Published
- Updated
- Reserved
- Assigned by
- GitHub_M
Description
comrak is a CommonMark + GFM compatible Markdown parser and renderer written in rust. A Comrak AST can be constructed manually by a program instead of parsing a Markdown document with `parse_document`. This AST can then be converted to HTML via `html::format_document_with_plugins`. However, the HTML formatting code assumes that the AST is well-formed. For example, many AST notes contain `[u8]` fields which the formatting code assumes is valid UTF-8 data. Several bugs can be triggered if this is not the case. Version 0.17.0 contains adjustments to the AST, storing strings instead of unvalidated byte arrays. Users are advised to upgrade. Users unable to upgrade may manually validate UTF-8 correctness of all data when assigning to `&[u8]` and `Vec<u8>` fields in the AST. This issue is also tracked as `GHSL-2023-049`.
Timeline
ID reserved
By GitHub_M
- 8 days later
· 8 days later
Published
- 23 months later
· 23 months later
Record updated
Changes after publication (a new score, a public exploit, EPSS crossing 1, 10 or 50 %, leaving KEV) are kept since November 2026; earlier ones are not known.
Scores
| Scored by | CVSS | Score | Vector |
|---|---|---|---|
| GitHub_MCNA (assigner) | 3.1 | Medium5.3 | CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:L |
| NVDNVD · Modified | 3.1 | Critical9.8 | CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:H/A:H |
- EPSS (exploitation in 30 days)
- 1.3% · top 30% of all CVEs (7 Nov 2026)
- CISA SSVC
- Exploitation: none · Automatable: yes · Technical impact: partial
The list uses the assigner's score when there is one, then CISA's, then NVD's: Medium 5.3.
Weakness
Affected products
Affected packages
From reviewed advisories of the GitHub Advisory Database.
- crates.iocomrakGHSA-5r3x-p7xx-x6q5 (opens in a new tab)
References (5)
- https://github.com/kivikakk/comrak/security/advisories/GHSA-5r3x-p7xx-x6q5 (opens in a new tab)x_refsource_CONFIRMx_transferred
- https://github.com/kivikakk/comrak/commit/9ff5f8df0ac951f5742d22a72c39b89a15f56639 (opens in a new tab)x_refsource_MISCx_transferred
- https://lists.fedoraproject.org/archives/list/[email protected]/message/PTWZWCT7KCX2KTXTLPUYZ3EHOONG4X46/ (opens in a new tab)x_transferred
- https://lists.fedoraproject.org/archives/list/[email protected]/message/OUYME2VA555X6567H7ORIJQFN4BVGT6N/ (opens in a new tab)x_transferred
- https://lists.fedoraproject.org/archives/list/[email protected]/message/VQ3UBC7LE4VPCMZBTADIBL353CH7CPVV/ (opens in a new tab)x_transferred
Sources
The same CVE in the primary databases and aggregators, to check against.
- CVE.org record (opens in a new tab)
- CVE List JSON (GitHub) (opens in a new tab)
- NVD (opens in a new tab)
- FIRST EPSS (opens in a new tab)
- OSV.dev (opens in a new tab)
- GitHub Advisory GHSA-5r3x-p7xx-x6q5 (opens in a new tab)
- CIRCL Vulnerability-Lookup (opens in a new tab)
Badge for a README or a ticket
[](https://trackcve.app/cve/CVE-2023-28631)Record last updated .