Vulnerability · Published Sep 22, 2023 · Assigned by GitHub_M
CVE-2023-42821github.com/gomarkdown/markdown Out-of-bounds Read while parsing citations
High 7.5
In plain English
A high-severity out-of-bounds read in markdown from gomarkdown. Proof-of-concept exploit code is public. The chance it is exploited in the next 30 days is estimated at 1.3% (higher than 70% of all known vulnerabilities). Fixed versions are available - upgrade the affected package.
Official description
The package `github.com/gomarkdown/markdown` is a Go library for parsing Markdown text and rendering as HTML. Prior to pseudoversion `0.0.0-20230922105210-14b16010c2ee`, which corresponds with commit `14b16010c2ee7ff33a940a541d993bd043a88940`, parsing malformed markdown input with parser that uses parser.Mmark extension could result in out-of-bounds read vulnerability. To exploit the vulnerability, parser needs to have `parser.Mmark` extension set. The panic occurs inside the `citation.go` file on the line 69 when the parser tries to access the element past its length. This can result in a denial of service. Commit `14b16010c2ee7ff33a940a541d993bd043a88940`/pseudoversion `0.0.0-20230922105210-14b16010c2ee` contains a patch for this issue.
Affected packages & fixed versions
| Ecosystem | Package | Fixed in | Advisory |
|---|---|---|---|
| Debian:12 | golang-github-gomarkdown-markdown | no fix listed | DEBIAN-CVE-2023-42821 |
| Debian:13 | golang-github-gomarkdown-markdown | 0.0~git20231115.a660076-1 | DEBIAN-CVE-2023-42821 |
| Debian:14 | golang-github-gomarkdown-markdown | 0.0~git20231115.a660076-1 | DEBIAN-CVE-2023-42821 |
| Go | github.com/gomarkdown/markdown | 0.0.0-20230922105210-14b16010c2ee | GHSA-m9xq-6h2j-65r2 |
| Go | github.com/gomarkdown/markdown | 0.0.0-20230922105210-14b16010c2ee | GO-2023-2074 |
| Ubuntu:24.04:LTS | golang-github-gomarkdown-markdown | no fix listed | UBUNTU-CVE-2023-42821 |
| Ubuntu:25.10 | golang-github-gomarkdown-markdown | no fix listed | UBUNTU-CVE-2023-42821 |
| Ubuntu:26.04:LTS | golang-github-gomarkdown-markdown | no fix listed | UBUNTU-CVE-2023-42821 |
| Ubuntu:26.10 | golang-github-gomarkdown-markdown | no fix listed | UBUNTU-CVE-2023-42821 |
Affected products (as reported)
| Vendor | Product | Versions |
|---|---|---|
| gomarkdown | markdown | < 0.0.0-20230922105210-14b16010c2ee |
Weakness: CWE-125 · Vector: CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:H
References
- https://github.com/gomarkdown/markdown/security/advisories/GHSA-m9xq-6h2j-65r2 x_refsource_CONFIRM
- https://github.com/gomarkdown/markdown/commit/14b16010c2ee7ff33a940a541d993bd043a88940 x_refsource_MISC
- https://github.com/gomarkdown/markdown/blob/7478c230c7cd3e7328803d89abe591d0b61c41e4/parser/citation.go#L69 x_refsource_MISC