CVE-2021-32919
It does not correctly authenticate remote server certificates, allowing a remote server to impersonate another server (when this option is enabled).
Does this matter?
High impact if exploited, but EPSS currently rates exploitation as unlikely (1.39%). Schedule it in the normal patch cycle and watch for a rise in EPSS or a public exploit.
Description
An issue was discovered in Prosody before 0.11.9. The undocumented dialback_without_dialback option in mod_dialback enables an experimental feature for server-to-server authentication. It does not correctly authenticate remote server certificates, allowing a remote server to impersonate another server (when this option is enabled).
- CVSS 3.1
- 7.5 HIGHCVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:N/A:N
- EPSS
- 1.39% probability · 72th percentile
- Public exploits
- None in Exploit-DB
- CISA KEV
- Not listed
- Weakness
- CWE-295
- Affected
- prosody/prosody · debian/debian linux · fedoraproject/fedora
- Source
- cve@mitre.org
EPSS 1.4% since 26 October 2026; no change recorded yet. Points are recorded when the score first appears and whenever it moves by a percentage point or more.
References
- http://www.openwall.com/lists/oss-security/2021/05/13/1Mailing List, Third Party Advisory
- http://www.openwall.com/lists/oss-security/2021/05/14/2Mailing List, Mitigation, Third Party Advisory
- https://blog.prosody.im/prosody-0.11.9-released/Release Notes, Vendor Advisory
- 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/202105-15Third Party Advisory
- https://www.debian.org/security/2021/dsa-4916Third Party Advisory
- http://www.openwall.com/lists/oss-security/2021/05/13/1Mailing List, Third Party Advisory
- http://www.openwall.com/lists/oss-security/2021/05/14/2Mailing List, Mitigation, Third Party Advisory
- https://blog.prosody.im/prosody-0.11.9-released/Release Notes, Vendor Advisory
- 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/202105-15Third Party Advisory
- https://www.debian.org/security/2021/dsa-4916Third Party Advisory
Source: NVD record, EPSS from FIRST.org, KEV from CISA, exploits from Exploit-DB. Refreshed daily. Download this record as JSON.