HOMEVULNERABILITIESCVE-2025-53940
HIGH

CVE-2025-53940

CWE-208Published: July 24, 2025· Updated: Jun 17, 2026

8.5
CVSS v3.1

Official Description

Quiet is an alternative to team chat apps like Slack, Discord, and Element that does not require trusting a central server or running one's own. In versions 6.1.0-alpha.4 and below, Quiet's API for backend/frontend communication was using an insecure, not constant-time comparison function for token verification. This allowed for a potential timing attack where an attacker would try different token values and observe tiny differences in the response time (wrong characters fail faster) to guess the whole token one character at a time. This is fixed in version 6.0.1.

NVD Source

Technical Analysis

CVE-2025-53940 requires local access, meaning attackers must already have a foothold on the target system.

Exploitation requires low privileges, which limits the exposure to scenarios where an attacker has already gained initial access.

CVSS v3.1 Vector Breakdown

Exploitability
Attack VectorLocal
Attack ComplexityHigh
Privileges Req.Low
User InteractionNone
ScopeX
Impact
Confidentiality
Integrity
Availability
CVSS:4.0/AV:L/AC:H/AT:N/PR:L/UI:N/VC:H/VI:H/VA:H/SC:H/SI:N/SA:N/E:X/CR:X/IR:X/AR:X/MAV:X/MAC:X/MAT:X/MPR:X/MUI:X/MVC:X/MVI:X/MVA:X/MSC:X/MSI:X/MSA:X/S:X/AU:X/R:X/V:X/RE:X/U:X

Affected Vendors & Products

Mentioned vendors (from description):
Slack
CPE data not yet available in NVD for this CVE.

Exploit & PoC Resources

NO KNOWN EXPLOITNo public exploit confirmed at this time
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All References (3)

Quick Facts

CVE IDCVE-2025-53940
CVSS Score8.5 / 10
SeverityHIGH
WeaknessCWE-208
CISA KEVNo
PublishedJul 24, 2025

Related CVEs (CWE-208)

Recommended Actions

  • Apply vendor patches immediately
  • Monitor CVE-2025-53940 in threat intel feeds
  • Review IDS/IPS signatures for exploitation attempts
Data sourced from NVD (NIST), CISA KEV, and EPSS (FIRST). Analysis generated by CTIWATCH.COM. CVE data is provided under the NVD usage policy.