Description
Balabit Syslog-NG 1.4.x before 1.4.15, and 1.5.x before 1.5.20, when using template filenames or output, does not properly track the size of a buffer when constant characters are encountered during macro expansion, which allows remote attackers to cause a denial of service and possibly 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 | syslog-ng | 1.5.21-1 | — |
| Debian 13 | syslog-ng | 1.5.21-1 | — |
| Debian 12 | syslog-ng | 1.5.21-1 | — |
| Debian 3.0 | syslog-ng | 1.5.15-1.1 | DSA-175 |
Advisories 1
- DSA-175 syslog-ng - buffer overflow Debian Security (DSA / DLA) · Mar 9, 2026
References
- http://www.balabit.hu/static/zsa/ZSA-2002-014-en.txt
- 5934 vdb-entry
- ESA-20021029-028 vendor-advisory
- syslogng-macro-expansion-bo(10339) vdb-entry
- SuSE-SA:2002:039 vendor-advisory
- CLA-2002:547 vendor-advisory
- 20021010 syslog-ng buffer overflow mailing-list
- DSA-175 vendor-advisory