What’s Vulnerable › Vulnerabilities

CVE-2021-32918

• Severity: high (CVSS 7.5 v3.1)
• Exploited in the wild: not listed in CISA KEV
• EPSS: 2.1% probability of exploitation in the next 30 days
• Public exploit or detection template: none known
• Published: 2021-05-13 · updated 2026-06-17
• Weakness: CWE-400

Description

An issue was discovered in Prosody before 0.11.9. Default settings are susceptible to remote unauthenticated denial-of-service (DoS) attacks via memory exhaustion when running under Lua 5.2 or Lua 5.3.

Affected products

• Debian Linux: 10.0
• Fedoraproject Fedora: 32, 33, 34
• Prosody: before 0.11.9 — fixed in 0.11.9

How to fix

Upgrade to a fixed version: Prosody 0.11.9. Check the vendor advisory for mitigations.

References

• http://www.openwall.com/lists/oss-security/2021/05/13/1
• http://www.openwall.com/lists/oss-security/2021/05/14/2
• https://blog.prosody.im/prosody-0.11.9-released/
• https://lists.fedoraproject.org/archives/list/package-announce%40lists.fedoraproject.org/message/6MFFBZWXKPZEVZNQSVJNCUE7WRF3T7DG/
• https://lists.fedoraproject.org/archives/list/package-announce%40lists.fedoraproject.org/message/GUN63AHEWB2WRROJHU3BVJRWLONCT2B7/
• https://lists.fedoraproject.org/archives/list/package-announce%40lists.fedoraproject.org/message/LWJ2DG2DFJOEFEWOUN26IMYYWGSA2ZEE/
• https://security.gentoo.org/glsa/202105-15
• https://www.debian.org/security/2021/dsa-4916
• http://www.openwall.com/lists/oss-security/2021/05/13/1
• http://www.openwall.com/lists/oss-security/2021/05/14/2
• https://blog.prosody.im/prosody-0.11.9-released/
• https://lists.fedoraproject.org/archives/list/package-announce%40lists.fedoraproject.org/message/6MFFBZWXKPZEVZNQSVJNCUE7WRF3T7DG/

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