Description
Format string vulnerability in hfaxd for Hylafax 4.1.7 and earlier allows remote attackers to execute arbitrary code.
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 | hylafax | 1:4.1.8-1 | — |
| Debian 13 | hylafax | 1:4.1.8-1 | — |
| Debian 12 | hylafax | 1:4.1.8-1 | — |
| Debian 3.0 | hylafax | 4.1.1-1.3 | DSA-401 |
Public exploits
Exploit or proof-of-concept code for this vulnerability is publicly available, which lowers the bar for attackers. Treat it as a reason to patch sooner.
Third-party code, not reviewed by us. Public PoCs are sometimes fake or contain malware. Read the code first and run it only in an isolated lab, against systems you are authorised to test.
Exploit-DB 1
- Hylafax 4.1.x - HFaxD Format String EDB-23371 · remote · Nov 10, 2003 · verified
Sources: PoC-in-GitHub, Metasploit Framework, Exploit-DB — updated daily. Only links are listed; no exploit code is hosted here.
Advisories 1
- DSA-401 hylafax - format strings Debian Security (DSA / DLA) · Mar 9, 2026
References
- DSA-401 vendor-advisory
- CLA-2003:783 vendor-advisory
- 20031111 HylaFAX - Format String Vulnerability Fixed mailing-list
- SuSE-SA:2003:045 vendor-advisory
- MDKSA-2003:105 vendor-advisory