The SMTP server in Postfix before 2.5.13, 2.6.x before 2.6.10, 2.7.x before 2.7.4, and 2.8.x before 2.8.3, when certain Cyrus SASL authentication methods are enabled, does not create a new server handle after client authentication fails, which allows remote attackers to cause a denial of service (heap memory corruption and daemon crash) or possibly execute arbitrary code via an invalid AUTH command with one method followed by an AUTH command with a different method.
Conclusion & alert: CVE-2011-1720 is rated Moderate Risk (56.3/100): CVSS Medium severity, with high exploitation likelihood (EPSS 21.65%, 97th percentile). Core evidence: EPSS ranks this CVE among the most likely to be exploited in the near term. Mandatory action: High exploitation likelihood—assess exposure and prioritize remediation.
Risk is dynamic; we continuously reassess and refresh what is shown on this page as upstream context changes.
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 | 2026-06-15 | 47.11% | 21.65% | -25.47% |
| 2 | 2026-06-13 | 45.15% | 47.11% | +1.96% |
| 3 | 2026-05-11 | — | 45.15% | — |
Full EPSS history (30 records total)
CVSS metrics for this CVE.
| Base score | Version | Severity | Vector | Exploitability | Impact | Score source |
|---|---|---|---|---|---|---|
| 6.8 | 2.0 | MEDIUM |
|
8.6 | 6.4 | [email protected] |
| vendor | priority | summary | link |
|---|---|---|---|
debian
|
not yet assigned | CVE-2011-1720 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-2011-1720 |
gentoo
|
high | CVE-2011-1720: 1 GLSA(s) (201206-33), 1 atom(s) (mail-mta/postfix); latest impact high. | https://bugs.gentoo.org/buglist.cgi?quicksearch=CVE-2011-1720 |
redhat
|
medium | — | https://access.redhat.com/security/cve/CVE-2011-1720 |
ubuntu
|
medium | CVE-2011-1720 medium priority: Ubuntu including 1 source packages (postfix), 6 status rows across 6 suites (dapper, hardy, lucid, maverick, natty, upstream): released 6. | https://ubuntu.com/security/CVE-2011-1720 |
| Vendor | Product | Version | Raw CPE |
|---|---|---|---|
| postfix | postfix | 2.0.0 | cpe:2.3:a:postfix:postfix:2.0.0:*:*:*:*:*:*:* |
| postfix | postfix | 2.0.1 | cpe:2.3:a:postfix:postfix:2.0.1:*:*:*:*:*:*:* |
| postfix | postfix | 2.0.2 | cpe:2.3:a:postfix:postfix:2.0.2:*:*:*:*:*:*:* |
| postfix | postfix | 2.0.3 | cpe:2.3:a:postfix:postfix:2.0.3:*:*:*:*:*:*:* |
| postfix | postfix | 2.0.4 | cpe:2.3:a:postfix:postfix:2.0.4:*:*:*:*:*:*:* |
| postfix | postfix | 2.0.5 | cpe:2.3:a:postfix:postfix:2.0.5:*:*:*:*:*:*:* |
| postfix | postfix | 2.0.6 | cpe:2.3:a:postfix:postfix:2.0.6:*:*:*:*:*:*:* |
| postfix | postfix | 2.0.7 | cpe:2.3:a:postfix:postfix:2.0.7:*:*:*:*:*:*:* |
| postfix | postfix | 2.0.8 | cpe:2.3:a:postfix:postfix:2.0.8:*:*:*:*:*:*:* |
| postfix | postfix | 2.0.9 | cpe:2.3:a:postfix:postfix:2.0.9:*:*:*:*:*:*:* |
| postfix | postfix | 2.0.10 | cpe:2.3:a:postfix:postfix:2.0.10:*:*:*:*:*:*:* |
| postfix | postfix | 2.0.11 | cpe:2.3:a:postfix:postfix:2.0.11:*:*:*:*:*:*:* |
| postfix | postfix | 2.0.12 | cpe:2.3:a:postfix:postfix:2.0.12:*:*:*:*:*:*:* |
| postfix | postfix | 2.0.13 | cpe:2.3:a:postfix:postfix:2.0.13:*:*:*:*:*:*:* |
| postfix | postfix | 2.0.14 | cpe:2.3:a:postfix:postfix:2.0.14:*:*:*:*:*:*:* |
| postfix | postfix | 2.0.15 | cpe:2.3:a:postfix:postfix:2.0.15:*:*:*:*:*:*:* |
| postfix | postfix | 2.0.16 | cpe:2.3:a:postfix:postfix:2.0.16:*:*:*:*:*:*:* |
| postfix | postfix | 2.0.17 | cpe:2.3:a:postfix:postfix:2.0.17:*:*:*:*:*:*:* |
| postfix | postfix | 2.0.18 | cpe:2.3:a:postfix:postfix:2.0.18:*:*:*:*:*:*:* |
| postfix | postfix | 2.0.19 | cpe:2.3:a:postfix:postfix:2.0.19:*:*:*:*:*:*:* |
| postfix | postfix | 2.1.0 | cpe:2.3:a:postfix:postfix:2.1.0:*:*:*:*:*:*:* |
| postfix | postfix | 2.1.1 | cpe:2.3:a:postfix:postfix:2.1.1:*:*:*:*:*:*:* |
| postfix | postfix | 2.1.2 | cpe:2.3:a:postfix:postfix:2.1.2:*:*:*:*:*:*:* |
| postfix | postfix | 2.1.3 | cpe:2.3:a:postfix:postfix:2.1.3:*:*:*:*:*:*:* |
| postfix | postfix | 2.1.4 | cpe:2.3:a:postfix:postfix:2.1.4:*:*:*:*:*:*:* |
| postfix | postfix | 2.1.5 | cpe:2.3:a:postfix:postfix:2.1.5:*:*:*:*:*:*:* |
| postfix | postfix | 2.1.6 | cpe:2.3:a:postfix:postfix:2.1.6:*:*:*:*:*:*:* |
| postfix | postfix | 2.2.0 | cpe:2.3:a:postfix:postfix:2.2.0:*:*:*:*:*:*:* |
| postfix | postfix | 2.2.1 | cpe:2.3:a:postfix:postfix:2.2.1:*:*:*:*:*:*:* |
| postfix | postfix | 2.2.2 | cpe:2.3:a:postfix:postfix:2.2.2:*:*:*:*:*:*:* |
| postfix | postfix | 2.2.3 | cpe:2.3:a:postfix:postfix:2.2.3:*:*:*:*:*:*:* |
| postfix | postfix | 2.2.4 | cpe:2.3:a:postfix:postfix:2.2.4:*:*:*:*:*:*:* |
| postfix | postfix | 2.2.5 | cpe:2.3:a:postfix:postfix:2.2.5:*:*:*:*:*:*:* |
| postfix | postfix | 2.2.6 | cpe:2.3:a:postfix:postfix:2.2.6:*:*:*:*:*:*:* |
| postfix | postfix | 2.2.7 | cpe:2.3:a:postfix:postfix:2.2.7:*:*:*:*:*:*:* |
| postfix | postfix | 2.2.8 | cpe:2.3:a:postfix:postfix:2.2.8:*:*:*:*:*:*:* |
| postfix | postfix | 2.2.9 | cpe:2.3:a:postfix:postfix:2.2.9:*:*:*:*:*:*:* |
| postfix | postfix | 2.2.10 | cpe:2.3:a:postfix:postfix:2.2.10:*:*:*:*:*:*:* |
| postfix | postfix | 2.2.11 | cpe:2.3:a:postfix:postfix:2.2.11:*:*:*:*:*:*:* |
| postfix | postfix | 2.2.12 | cpe:2.3:a:postfix:postfix:2.2.12:*:*:*:*:*:*:* |
| postfix | postfix | 2.3 | cpe:2.3:a:postfix:postfix:2.3:*:*:*:*:*:*:* |
| postfix | postfix | 2.3.0 | cpe:2.3:a:postfix:postfix:2.3.0:*:*:*:*:*:*:* |
| postfix | postfix | 2.3.1 | cpe:2.3:a:postfix:postfix:2.3.1:*:*:*:*:*:*:* |
| postfix | postfix | 2.3.2 | cpe:2.3:a:postfix:postfix:2.3.2:*:*:*:*:*:*:* |
| postfix | postfix | 2.3.3 | cpe:2.3:a:postfix:postfix:2.3.3:*:*:*:*:*:*:* |
| postfix | postfix | 2.3.4 | cpe:2.3:a:postfix:postfix:2.3.4:*:*:*:*:*:*:* |
| postfix | postfix | 2.3.5 | cpe:2.3:a:postfix:postfix:2.3.5:*:*:*:*:*:*:* |
| postfix | postfix | 2.3.6 | cpe:2.3:a:postfix:postfix:2.3.6:*:*:*:*:*:*:* |
| postfix | postfix | 2.3.7 | cpe:2.3:a:postfix:postfix:2.3.7:*:*:*:*:*:*:* |
| postfix | postfix | 2.3.8 | cpe:2.3:a:postfix:postfix:2.3.8:*:*:*:*:*:*:* |
| postfix | postfix | 2.3.9 | cpe:2.3:a:postfix:postfix:2.3.9:*:*:*:*:*:*:* |
| postfix | postfix | 2.3.10 | cpe:2.3:a:postfix:postfix:2.3.10:*:*:*:*:*:*:* |
| postfix | postfix | 2.3.11 | cpe:2.3:a:postfix:postfix:2.3.11:*:*:*:*:*:*:* |
| postfix | postfix | 2.3.12 | cpe:2.3:a:postfix:postfix:2.3.12:*:*:*:*:*:*:* |
| postfix | postfix | 2.3.13 | cpe:2.3:a:postfix:postfix:2.3.13:*:*:*:*:*:*:* |
| postfix | postfix | 2.3.14 | cpe:2.3:a:postfix:postfix:2.3.14:*:*:*:*:*:*:* |
| postfix | postfix | 2.3.15 | cpe:2.3:a:postfix:postfix:2.3.15:*:*:*:*:*:*:* |
| postfix | postfix | 2.3.16 | cpe:2.3:a:postfix:postfix:2.3.16:*:*:*:*:*:*:* |
| postfix | postfix | 2.3.17 | cpe:2.3:a:postfix:postfix:2.3.17:*:*:*:*:*:*:* |
| postfix | postfix | 2.3.18 | cpe:2.3:a:postfix:postfix:2.3.18:*:*:*:*:*:*:* |
| postfix | postfix | 2.3.19 | cpe:2.3:a:postfix:postfix:2.3.19:*:*:*:*:*:*:* |
| postfix | postfix | 2.4 | cpe:2.3:a:postfix:postfix:2.4:*:*:*:*:*:*:* |
| postfix | postfix | 2.4.0 | cpe:2.3:a:postfix:postfix:2.4.0:*:*:*:*:*:*:* |
| postfix | postfix | 2.4.1 | cpe:2.3:a:postfix:postfix:2.4.1:*:*:*:*:*:*:* |
| postfix | postfix | 2.4.2 | cpe:2.3:a:postfix:postfix:2.4.2:*:*:*:*:*:*:* |
| postfix | postfix | 2.4.3 | cpe:2.3:a:postfix:postfix:2.4.3:*:*:*:*:*:*:* |
| postfix | postfix | 2.4.4 | cpe:2.3:a:postfix:postfix:2.4.4:*:*:*:*:*:*:* |
| postfix | postfix | 2.4.5 | cpe:2.3:a:postfix:postfix:2.4.5:*:*:*:*:*:*:* |
| postfix | postfix | 2.4.6 | cpe:2.3:a:postfix:postfix:2.4.6:*:*:*:*:*:*:* |
| postfix | postfix | 2.4.7 | cpe:2.3:a:postfix:postfix:2.4.7:*:*:*:*:*:*:* |
| postfix | postfix | 2.4.8 | cpe:2.3:a:postfix:postfix:2.4.8:*:*:*:*:*:*:* |
| postfix | postfix | 2.4.9 | cpe:2.3:a:postfix:postfix:2.4.9:*:*:*:*:*:*:* |
| postfix | postfix | 2.4.10 | cpe:2.3:a:postfix:postfix:2.4.10:*:*:*:*:*:*:* |
| postfix | postfix | 2.4.11 | cpe:2.3:a:postfix:postfix:2.4.11:*:*:*:*:*:*:* |
| postfix | postfix | 2.4.12 | cpe:2.3:a:postfix:postfix:2.4.12:*:*:*:*:*:*:* |
| postfix | postfix | 2.4.13 | cpe:2.3:a:postfix:postfix:2.4.13:*:*:*:*:*:*:* |
| postfix | postfix | 2.4.14 | cpe:2.3:a:postfix:postfix:2.4.14:*:*:*:*:*:*:* |
| postfix | postfix | 2.4.15 | cpe:2.3:a:postfix:postfix:2.4.15:*:*:*:*:*:*:* |
| postfix | postfix | 2.5.0 | cpe:2.3:a:postfix:postfix:2.5.0:*:*:*:*:*:*:* |
| postfix | postfix | 2.5.1 | cpe:2.3:a:postfix:postfix:2.5.1:*:*:*:*:*:*:* |