CVE-2004-2677: Format string vulnerability in qwik-smtpd.c in QwikMail SMTP (qwik-smtpd) 0.3 and earlier allows remote attack

This month

HIGH 7.5DOWNGRADE

CVE-2004-2677 is a high-severity flaw (CVSS 7.5) affecting qwikmail smtp. Below: why it ranks where it does, which versions are affected, what to do, and the exact commands.

Format string vulnerability in qwik-smtpd.c in QwikMail SMTP (qwik-smtpd) 0.3 and earlier allows remote attackers to execute arbitrary code via format specifiers in the (1) clientRcptTo array, and the (2) Received and (3) messageID variables, possibly involving HELO and hostname arguments.

Why this priority

High severity
EPSS top 6%: very likely to be exploited
Public exploit reference

No fix is published yet: follow the downgrade or mitigation steps.

Risk facts

CVSS score	7.5 (High)
EPSS exploit chance	6.5% (top 6%)
CISA exploited list	No
Published	2004-12-31
Last modified	2026-06-16

Publisher (CNA): MITRE · Vendor: qwikmail

Last updated 2026-06-16 · Sources: CVE Program, NVD, CISA KEV, EPSS and vendor advisories · How we score

Am I affected?

Timeline

2004-12-31 05:00 UTCPublished CVE record published
2026-06-16 22:10 UTCUpdated Record last modified

qwikmail qwikmail smtp DOWNGRADE

Affected: 0.3

Fixed in: no fixed release known

Safe to downgrade to: a release before 0.3

1. Check installed version

apt-cache policy qwikmail-smtp || rpm -q qwikmail-smtp || qwikmail-smtp --version

2. No fixed release: DOWNGRADE to a release before 0.3 (Debian / Ubuntu)

apt-cache madison qwikmail-smtp sudo apt install qwikmail-smtp=<VERSION_BEFORE_0.3> sudo apt-mark hold qwikmail-smtp

2. No fixed release: DOWNGRADE (RHEL / Amazon Linux / Fedora)

dnf --showduplicates list qwikmail-smtp sudo dnf downgrade qwikmail-smtp-<VERSION_BEFORE_0.3> sudo dnf versionlock add qwikmail-smtp

Downgrade risk

Downgrading can break dependent software and may reopen older bugs. Read the distro advisory first and test on a non-production host.

After downgrade

Restart the service, and keep the package held until a fixed release ships.

Public exploits and detection

Public code exists for this CVE. Treat unpatched systems as at risk, and only run PoCs in a lab.

Exploit-DB: Qwik SMTP 0.3 - Format String

Verify at the official source NVD · CVE Program · Report a problem with this page
Scores and fixes here are computed automatically from those and other public sources. Confirm with the vendor advisory before changing production systems.

Quick answers

How do I fix CVE-2004-2677?

qwikmail smtp: downgrade or apply the listed mitigation. Exact commands for each OS are on this page.

Is CVE-2004-2677 being exploited?

CVE-2004-2677 is not on the CISA Known Exploited Vulnerabilities list at the time of the last update. Check again, as this can change.

What does CVE-2004-2677 affect?

CVE-2004-2677 affects qwikmail smtp. Severity is high (CVSS 7.5). Format string vulnerability in qwik-smtpd.c in QwikMail SMTP (qwik-smtpd) 0.3 and earlier allows remote attackers to execute arbitrary code via format specifiers in the (1) clientRcptTo array, and the (2) Received and (3) messageID variable

How urgent is CVE-2004-2677?

Priority 55/100. High severity; EPSS top 6%: very likely to be exploited; Public exploit reference

References

← Back to latest CVEs