Description
The getmxrecord function in Fetchmail 6.0.0 and earlier does not properly check the boundary of a particular malformed DNS packet from a malicious DNS server, which allows remote attackers to cause a denial of service (crash) when Fetchmail attempts to read data beyond the expected boundary.
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 | fetchmail | 6.1.0-1 | — |
| Debian 13 | fetchmail | 6.1.0-1 | — |
| Debian 12 | fetchmail | 6.1.0-1 | — |
| Debian 3.0 | fetchmail +1 | 5.9.11-6.1 | DSA-171 |
Advisories 1
- DSA-171 fetchmail - buffer overflows Debian Security (DSA / DLA) · Mar 9, 2026
References
- MDKSA-2002:063 vendor-advisory
- 20020929 Advisory 03/2002: Fetchmail remote vulnerabilities mailing-list
- RHSA-2002:215 vendor-advisory
- fetchmail-multidrop-bo(10203) vdb-entry
- CLA-2002:531 vendor-advisory
- ESA-20021003-023 vendor-advisory
- 5826 vdb-entry
- DSA-171 vendor-advisory