CVE-2005-2409: Format string vulnerability in util.c in nbsmtp 0.99 and earlier, while running in debug mode, allows remote a

Q: How do I fix CVE-2005-2409?

nbsmtp: upgrade to newer than 0.99. Exact commands for each OS are on this page.

Q: Is CVE-2005-2409 being exploited?

CVE-2005-2409 is not on the CISA Known Exploited Vulnerabilities list at the time of the last update. Check again, as this can change.

Q: What does CVE-2005-2409 affect?

CVE-2005-2409 affects nbsmtp. Severity is high (CVSS 7.5). Format string vulnerability in util.c in nbsmtp 0.99 and earlier, while running in debug mode, allows remote attackers to execute arbitrary code via format string specifiers that are not properly handled in a syslog call.

Q: How urgent is CVE-2005-2409?

Priority 55/100. High severity; EPSS top 4%: very likely to be exploited; Public exploit reference

This week

HIGH 7.5UPGRADE

CVE-2005-2409 is a high-severity flaw (CVSS 7.5) affecting nbsmtp. Below: why it ranks where it does, which versions are affected, what to do, and the exact commands.

Format string vulnerability in util.c in nbsmtp 0.99 and earlier, while running in debug mode, allows remote attackers to execute arbitrary code via format string specifiers that are not properly handled in a syslog call.

Why this priority

High severity
EPSS top 4%: very likely to be exploited
Public exploit reference

A fixed release or distro patch exists.

Risk facts

CVSS score	7.5 (High)
EPSS exploit chance	9.9% (top 4%)
CISA exploited list	No
Published	2005-08-01
Last modified	2026-06-16

Publisher (CNA): MITRE · Vendor: nbsmtp

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

Am I affected?

Timeline

2005-08-01 04:00 UTCPublished CVE record published
2026-06-16 22:14 UTCUpdated Record last modified

nbsmtp nbsmtp UPGRADE

Affected: <= 0.99

Fixed in: newer than 0.99

Safe to downgrade to: no unaffected older release

1. Check installed version

apt-cache policy nbsmtp || rpm -q nbsmtp || nbsmtp --version

2. UPGRADE to newer than 0.99 (Debian / Ubuntu)

sudo apt update && sudo apt install --only-upgrade nbsmtp

2. UPGRADE (RHEL / Amazon Linux / Fedora)

sudo dnf upgrade nbsmtp

Note

Distros often backport fixes without changing the version number. Confirm with the distro advisory or changelog.

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: nbSMTP 0.99 - 'util.c' Client-Side Command Execution

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-2005-2409?

nbsmtp: upgrade to newer than 0.99. Exact commands for each OS are on this page.

Is CVE-2005-2409 being exploited?

CVE-2005-2409 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-2005-2409 affect?

CVE-2005-2409 affects nbsmtp. Severity is high (CVSS 7.5). Format string vulnerability in util.c in nbsmtp 0.99 and earlier, while running in debug mode, allows remote attackers to execute arbitrary code via format string specifiers that are not properly handled in a syslog call.

How urgent is CVE-2005-2409?

Priority 55/100. High severity; EPSS top 4%: very likely to be exploited; Public exploit reference

References

← Back to latest CVEs