Description
fetchmail 6.3.8 and earlier, when running in -v -v (aka verbose) mode, allows remote attackers to cause a denial of service (crash and persistent mail failure) via a malformed mail message with long headers, which triggers an erroneous dereference when using vsnprintf to format log messages.
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 | 6.3.9~rc2-1 | — |
| Debian 13 | fetchmail | 6.3.9~rc2-1 | — |
| Debian 12 | fetchmail | 6.3.9~rc2-1 | — |
Red Hat
Security tracker ↗| Release | Package | Fixed in | Advisory |
|---|---|---|---|
| RHEL 5 | fetchmail | 6.3.6-1.1.el5_3.1 | RHSA-2009:1427 |
| RHEL 4 | fetchmail | 6.2.5-6.0.1.el4_8.1 | RHSA-2009:1427 |
| RHEL 3 | fetchmail | 6.2.0-3.el3.5 | RHSA-2009:1427 |
Advisories 1
- RHSA-2009:1427 Red Hat Security Advisory: fetchmail security update Red Hat Security Advisories (RHSA) · Jun 26, 2026
References
- ADV-2008-1860 vdb-entry
- 31287 third-party-advisory
- 20080729 rPSA-2008-0235-1 fetchmail fetchmailconf mailing-list
- 1020298 vdb-entry
- 33937 third-party-advisory
- 20080617 fetchmail security announcement fetchmail-SA-2008-01 (CVE-2008-2711) mailing-list
- 31262 third-party-advisory
- http://wiki.rpath.com/wiki/Advisories:rPSA-2008-0235
- http://support.apple.com/kb/HT3438
- APPLE-SA-2009-02-12 vendor-advisory
- 30895 third-party-advisory
- FEDORA-2008-5800 vendor-advisory
- FEDORA-2008-5789 vendor-advisory
- SSA:2008-210-01 vendor-advisory
- http://www.fetchmail.info/fetchmail-SA-2008-01.txt
- ADV-2009-0422 vdb-entry
- 29705 vdb-entry
- https://issues.rpath.com/browse/RPL-2623
- https://bugzilla.novell.com/show_bug.cgi?id=354291
- MDVSA-2008:117 vendor-advisory
- fetchmail-logmessage-dos(43121) vdb-entry
- [oss-security] 20080613 CVE Id Request: fetchmail <= 6.3.8 DoS when logging long headers in -v -v mode mailing-list
- oval:org.mitre.oval:def:10950 vdb-entry signature
- 30742 third-party-advisory
- [oss-security] 20210809 fetchmail 6.4.21 released/regression fix for 6.4.20's security fix, and UPDATE: fetchmail <= 6.4.19 security announcement 2021-01 (CVE-2021-36386) mailing-list