Session hijacking via timestamp-derived authentication cookies
Published Aug 30, 2026 · Updated Aug 30, 2026
Insufficient randomness in TOTOLINK N600R 4.3.0cu.7866_B20220506 allows remote attackers to hijack an authenticated router session. The loginAuth handler in /web_cste/cgi-bin/cstecgi.cgi derives cookie_key by hashing the current Unix timestamp with MD5, allowing recent values to be enumerated. No credentials or user interaction are required, but success depends on finding a still-valid timestamp-derived cookie and grants only that session's access.
Summary
What happened
Insufficient randomness in TOTOLINK N600R 4.3.0cu.7866_B20220506 allows remote attackers to hijack an authenticated router session. The loginAuth handler in /web_cste/cgi-bin/cstecgi.cgi derives cookie_key by hashing the current Unix timestamp with MD5, allowing recent values to be enumerated. No credentials or user interaction are required, but success depends on finding a still-valid timestamp-derived cookie and grants only that session's access.
The record
- CVE
- CVE-2026-82555
- Published
- Aug 30, 2026
- Updated
- Aug 30, 2026
- Vendor
- TOTOLINK
- Product
- N600R
- Classifications
- CWE-310, CWE-330, T1550.004
- Attack vector
- network
- Privileges
- unauthenticated
Timeline
How it unfolded
- Aug 30, 2026CVE publishedPublication date reported by the CVE source.
- Aug 30, 2026Record 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.
- Affected versionversion=4.3.0cu.7866_B20220506
What conditions does exploitation require?
What is affected?
Published CVSS scores
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.
Weakness, pattern, technique
Public exploit references
- TOTOLINK N600R predictable-token poc.pyproof of concept · unverified
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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