Local client crash via unbounded settings allocation
Published Aug 26, 2026 · Updated Aug 27, 2026
Denial of service in TokTok qTox 1.18.4 allows local users to crash the client by loading a crafted settings file from the profile directory. SettingsSerializer::readStream() decodes an attacker-controlled variable-length size without an overflow or length bound, then passes it to QByteArray::resize(). The attacker needs local write access to a profile settings file; starting qTox then requests an approximately 2 GB allocation and terminates the process.
Summary
What happened
Denial of service in TokTok qTox 1.18.4 allows local users to crash the client by loading a crafted settings file from the profile directory. SettingsSerializer::readStream() decodes an attacker-controlled variable-length size without an overflow or length bound, then passes it to QByteArray::resize(). The attacker needs local write access to a profile settings file; starting qTox then requests an approximately 2 GB allocation and terminates the process.
The record
- CVE
- CVE-2026-51106
- Published
- Aug 26, 2026
- Updated
- Aug 27, 2026
- Vendor
- Unknown vendor
- Product
- Unknown product
- Classifications
- T1499
- Attack vector
- local
- Privileges
- Unavailable
Timeline
How it unfolded
- Aug 26, 2026CVE publishedPublication date reported by the CVE source.
- Aug 27, 2026Record updatedLatest update available in the CVE record.
Exploitability
Present is not the same as exploitable
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What is affected?
Affected products and versions are unavailable in this record.
Published CVSS scores
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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.
Weakness, pattern, technique
Public exploit references
- poc_settingsserializer_crash.pyproof of concept · demonstrated
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Technologies
Your stack
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Your stack
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