CVE-2021-22929Public exploit

Tor browsing-time disclosure via persistent warning logs

Published Aug 31, 2021 · Updated Aug 3, 2024

Information disclosure in Brave Browser Desktop before 1.28.62 allows local users to infer Tor browsing times from tor.log. Brave writes Tor control-channel warnings for V2 onion connections, including timestamps, to the on-disk tor.log file. Local access to the user's profile is required; correlation with external connection records reveals when V2 onion sites were visited.

CVSS severity6.1
Medium
EPSS probability0.40%
Next 30 days · Sep 16, 2026
Known exploitationUnconfirmed
Based on sourced intelligence
Hinoki checkNot available
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Summary

What happened

Information disclosure in Brave Browser Desktop before 1.28.62 allows local users to infer Tor browsing times from tor.log. Brave writes Tor control-channel warnings for V2 onion connections, including timestamps, to the on-disk tor.log file. Local access to the user's profile is required; correlation with external connection records reveals when V2 onion sites were visited.

The record

CVE
CVE-2021-22929
Published
Aug 31, 2021
Updated
Aug 3, 2024
Vendor
Brave
Product
Brave Browser
Classifications
CWE-532, CWE-312, T1005
Attack vector
local
Privileges
authenticated

Timeline

How it unfolded

  1. Aug 31, 2021CVE publishedPublication date reported by the CVE source.
  2. Aug 3, 2024Record 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=1.28.62

What conditions does exploitation require?

Attack vectorlocal
Required privilegesauthenticated

What is affected?

Brave · Brave Browserversion=1.28.62

Published CVSS scores

6.1NIST NVDCVSS:3.1/AV:L/AC:L/PR:L/UI:N/S:U/C:L/I:H/A:N
3.6NIST NVDAV:L/AC:L/Au:N/C:P/I:P/A: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.

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No observations available

Sep 9, 2026Sep 15, 2026
Latest reporting daySep 15, 2026
Latest daily unique IPsUnavailable
Prior 30-day averageUnavailable
SourceShadowserver honeypots (KEV)
Vectorlocal
Privilegesauthenticated
Known exploitationUnconfirmed
Public exploitPublished

Weakness, pattern, technique

CWE-532Insertion of Sensitive Information into Log File
CWE-312Cleartext Storage of Sensitive Information
T1005Data from Local System

Public exploit references

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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