CVE-2003-0540

Exp

The address parser code in Postfix 1.1.12 and earlier allows remote attackers to cause a denial of service (lock) via (1) a malformed envelope address to a local host that would generate a bounce and contains the ".!" string in the MAIL FROM or Errors-To headers, which causes nqmgr to lock up, or (2) via a valid MAIL FROM with a RCPT TO containing a ".!" string, which causes an instance of the SMTP listener to lock up.

Published: 2003-08-27 Last update: 2026-04-16 Assigner: [email protected] Source: [email protected]

Conclusion & alert: CVE-2003-0540 is rated High Exploit Risk (72.4/100): CVSS Medium severity, with high exploitation likelihood (EPSS 57.49%, 98th percentile). Core evidence: 2 public exploit reference(s) are indexed (Exploit-DB). EPSS rose +3.09% over the last day, indicating growing attacker interest. Mandatory action: Public exploits are available—assess exposure, apply mitigations, and prioritize patching.

Risk is dynamic; we continuously reassess and refresh what is shown on this page as upstream context changes.

Public exploit references (Exploit-DB) for CVE-2003-0540

EDB-ID Source Kind Published Link
22982 exploit_db edb 2003-08-04 Exploit-DB ↗
22981 exploit_db edb 2003-08-04 Exploit-DB ↗

Exploit prediction scoring system (EPSS) score for CVE-2003-0540

EPSS lead: Daily EPSS estimates relative likelihood of exploitation; percentile ranks this CVE among scored vulnerabilities (higher = more severe relative rank).

# Date Old EPSS score New EPSS score Delta (New - Old)
1 2025-04-09 54.40% 57.49% +3.09%
2 2025-03-30 48.19% 54.40% +6.21%
3 2025-03-29 48.19%

Full EPSS history (9 records total)

Common vulnerability scoring system (CVSS) metrics for CVE-2003-0540

CVSS metrics for this CVE.

Base score Version Severity Vector Exploitability Impact Score source
5.0 2.0 MEDIUM
AV:N/AC:L/Au:N/C:N/I:N/A:P Click to expand
Access vector (AV:N)
Can be exploited remotely over network reachability.
Access complexity (AC:L)
Exploitation conditions are straightforward and predictable.
Authentication (AU:N)
No authentication is required.
Confidentiality impact (C:N)
No confidentiality impact.
Integrity impact (I:N)
No integrity impact.
Availability impact (A:P)
Partial availability impact.
10.0 2.9 [email protected]

Weakness enumeration for CVE-2003-0540

OS Trackers for CVE-2003-0540

vendor priority summary link
debian not yet assigned CVE-2003-0540 not yet assigned priority: Debian including 1 source packages (postfix), 5 status rows across 5 suites (bookworm, bullseye, forky, sid, trixie): resolved 5. https://security-tracker.debian.org/tracker/CVE-2003-0540
redhat https://access.redhat.com/security/cve/CVE-2003-0540

Affected software / configurations for CVE-2003-0540

Vendor Product Version Raw CPE
wietse_venema postfix 1.0.21 cpe:2.3:a:wietse_venema:postfix:1.0.21:*:*:*:*:*:*:*
wietse_venema postfix 1.1.11 cpe:2.3:a:wietse_venema:postfix:1.1.11:*:*:*:*:*:*:*
wietse_venema postfix 1.1.12 cpe:2.3:a:wietse_venema:postfix:1.1.12:*:*:*:*:*:*:*
wietse_venema postfix 1999-09-06 cpe:2.3:a:wietse_venema:postfix:1999-09-06:*:*:*:*:*:*:*
wietse_venema postfix 1999-12-31 cpe:2.3:a:wietse_venema:postfix:1999-12-31:*:*:*:*:*:*:*
wietse_venema postfix 2000-02-28 cpe:2.3:a:wietse_venema:postfix:2000-02-28:*:*:*:*:*:*:*
wietse_venema postfix 2001-11-15 cpe:2.3:a:wietse_venema:postfix:2001-11-15:*:*:*:*:*:*:*
conectiva linux 7.0 cpe:2.3:o:conectiva:linux:7.0:*:*:*:*:*:*:*
conectiva linux 8.0 cpe:2.3:o:conectiva:linux:8.0:*:*:*:*:*:*:*

References for CVE-2003-0540

URL Tags
http://distro.conectiva.com.br/atualizacoes/?id=a&anuncio=000717
http://lists.grok.org.uk/pipermail/full-disclosure/2003-August/007693.html
http://marc.info/?l=bugtraq&m=106001525130257&w=2
http://marc.info/?l=bugtraq&m=106029188614704&w=2
http://secunia.com/advisories/9433
http://www.debian.org/security/2003/dsa-363 Patch Vendor Advisory
http://www.kb.cert.org/vuls/id/895508 US Government Resource
http://www.linuxsecurity.com/advisories/engarde_advisory-3517.html
http://www.mandriva.com/security/advisories?name=MDKSA-2003:081
http://www.novell.com/linux/security/advisories/2003_033_postfix.html
http://www.redhat.com/support/errata/RHSA-2003-251.html Patch Vendor Advisory
http://www.securityfocus.com/bid/8333
https://oval.cisecurity.org/repository/search/definition/oval%3Aorg.mitre.oval%3Adef%3A544
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