An issue was discovered in Prosody before 0.11.9.
Priority LOW 30CWE-362Published · Updated
Key facts
- Attack vector
- Network
- Privileges required
- None
- User interaction
- None
- Attack complexity
- High
- Impact type
- —
- Confidentiality · integrity · availability
- High · None · None
- Fix status
- No fix listed
Attack profile from CVSS 3.1 · NVD. Fix status from CNA.
Summary
An issue was discovered in Prosody before 0.11.9. It does not use a constant-time algorithm for comparing certain secret strings when running under Lua 5.2 or later. This can potentially be used in a timing attack to reveal the contents of secret strings to an attacker.
Why it matters now
EPSS 0.01601 75th percentileScored 2026-11-07
Fix No fix listed No fixed version in the sources yet
SSVC decision points
Not available: CISA has not published SSVC decision points for this record.
Affected products
| Vendor | Product | Affected versions | Fixed in | Status | Source |
|---|---|---|---|---|---|
| — | — | all versions | — | No fix listed | CNA |
- — Vendor— Affected all versions Fixed in — No fix listed CNA
CPE configurations NVD · 6
| CPE | Versions | Role | Vendor |
|---|---|---|---|
| cpe:2.3:a:prosody:prosody:*:*:*:*:*:*:*:* | before 0.11.9 | Vulnerable | Prosody |
| cpe:2.3:a:lua:lua:*:*:*:*:*:*:*:* | 5.2.0 | Running on | Lua |
| cpe:2.3:o:fedoraproject:fedora:32:*:*:*:*:*:*:* | 32 | Vulnerable | Fedoraproject |
| cpe:2.3:o:fedoraproject:fedora:33:*:*:*:*:*:*:* | 33 | Vulnerable | Fedoraproject |
| cpe:2.3:o:fedoraproject:fedora:34:*:*:*:*:*:*:* | 34 | Vulnerable | Fedoraproject |
| cpe:2.3:o:debian:debian_linux:9.0:*:*:*:*:*:*:* | 9.0 | Vulnerable | Debian |
- cpe:2.3:a:prosody:prosody:*:*:*:*:*:*:*:* Versions before 0.11.9 Vulnerable ·Prosody
- cpe:2.3:a:lua:lua:*:*:*:*:*:*:*:* Versions 5.2.0 Running on ·Lua
- cpe:2.3:o:fedoraproject:fedora:32:*:*:*:*:*:*:* Versions 32 Vulnerable ·Fedoraproject
- cpe:2.3:o:fedoraproject:fedora:33:*:*:*:*:*:*:* Versions 33 Vulnerable ·Fedoraproject
- cpe:2.3:o:fedoraproject:fedora:34:*:*:*:*:*:*:* Versions 34 Vulnerable ·Fedoraproject
- cpe:2.3:o:debian:debian_linux:9.0:*:*:*:*:*:*:* Versions 9.0 Vulnerable ·Debian
Remediation
No fixed version listed by the sources yet.
Vendor assessments
Timeline
- 2026-10-02 Threatist record created from CVE-2021-32921
- 2026-10-03 Alias added: GHSA-vh63-h6gp-hw6w
References
Advisory 10
- https://blog.prosody.im/prosody-0.11.9-released/
- [oss-security] 20210513 Prosody XMPP server advisory 2021-05-12 (multiple vulnerabilities)
- [oss-security] 20210514 Re: Prosody XMPP server advisory 2021-05-12 (multiple vulnerabilities)
- DSA-4916
- FEDORA-2021-b5d8c6d086
- FEDORA-2021-a33f6e36e1
- FEDORA-2021-498be8f560
- https://security.gentoo.org/glsa/202105-15
- [debian-lts-announce] 20210616 [SECURITY] [DLA 2687-1] prosody security update
- [debian-lts-announce] 20210619 [SECURITY] [DLA 2687-2] prosody regression update
Sources
- CVE-2021-32921 · CVE Program
- CVE-2021-32921 · NVD
- FIRST EPSS
- GHSA-vh63-h6gp-hw6w · GitHub Advisory Database · CC BY 4.0
- CVE-2021-32921 · Red Hat security data · CC BY 4.0
This product uses the NVD API but is not endorsed or certified by the NVD. Sources and licences