Description
md_push_block_bytes in md4c.c in md4c 0.4.5 allows attackers to trigger use of uninitialized memory, and cause a denial of service (e.g., assertion failure) via a malformed Markdown document.
Fixed in Linux distributions
Distributions backport fixes, so the version that fixes this vulnerability differs per release — upgrade to at least the version shown. From the distributions' security trackers and advisories.
Debian
Security tracker ↗| Release | Package | Fixed in | Advisory |
|---|---|---|---|
| Debian 14 | md4c | 0.4.5-2 | — |
| Debian 13 | md4c | 0.4.5-2 | — |
| Debian 12 | md4c | 0.4.5-2 | — |
Ubuntu
Security tracker ↗| Release | Package | Fixed in | Advisory |
|---|---|---|---|
| Ubuntu 20.04 LTS | md4c | No fix yet | — |