CVE-2025-53940

Local account takeover via token timing oracle

Published Jul 24, 2025 · Updated Jul 25, 2025

Observable timing discrepancy in TryQuiet Quiet before 6.0.1 allows local users to recover the backend API token through timed guesses. The backend/frontend API compares supplied token values with a non-constant-time function, causing wrong characters to fail faster. Code running on the same device, including another account or a malicious app or extension, can gain full account access and obtain an invite link; websites and other devices cannot reach the flaw.

CVSS severity8.5
High
EPSS probability3.17%
Next 30 days · Sep 16, 2026
Known exploitationUnconfirmed
Based on sourced intelligence
Hinoki checkNot available
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Summary

What happened

Observable timing discrepancy in TryQuiet Quiet before 6.0.1 allows local users to recover the backend API token through timed guesses. The backend/frontend API compares supplied token values with a non-constant-time function, causing wrong characters to fail faster. Code running on the same device, including another account or a malicious app or extension, can gain full account access and obtain an invite link; websites and other devices cannot reach the flaw.

The record

CVE
CVE-2025-53940
Published
Jul 24, 2025
Updated
Jul 25, 2025
Vendor
TryQuiet
Product
Quiet
Classifications
CWE-208, T1528
Attack vector
local
Privileges
authenticated

Timeline

How it unfolded

  1. Jul 24, 2025CVE publishedPublication date reported by the CVE source.
  2. Jul 25, 2025Record updatedLatest update available in the CVE record.

Exploitability

Present is not the same as exploitable

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Is a vulnerable build present?

Compare these published version ranges with your installed build and any vendor patches.

  1. Affected versionversion=< 6.0.1

What conditions does exploitation require?

Attack vectorlocal
Required privilegesauthenticated

What is affected?

TryQuiet · Quietversion=< 6.0.1

Published CVSS scores

8.5GitHub, Inc.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

CVSS describes severity. EPSS estimates exploitation probability.

Attacks

What attackers are doing with it

Daily unique IPs observed by Shadowserver honeypots for known exploited vulnerabilities (KEVs). Missing observations do not establish an absence of attacks.

Daily unique IPsNo honeypot observations are available for this CVE in the selected window.

No observations available

Sep 10, 2026Sep 16, 2026
Latest reporting daySep 16, 2026
Latest daily unique IPsUnavailable
Prior 30-day averageUnavailable
SourceShadowserver honeypots (KEV)
Vectorlocal
Privilegesauthenticated
Known exploitationUnconfirmed
Public exploitUnconfirmed

Weakness, pattern, technique

CWE-208Observable Timing Discrepancy
T1528Steal Application Access Token

Public exploit references

No public exploit references are available in this record.

Labels summarize the accepted research assessment. They do not indicate a test against your environment.

Technologies

Your stack

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Your stack

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