Token forgery via bcrypt input truncation
Published Jun 19, 2020 · Updated Aug 5, 2024
Weak token hashing in Mattermost Server before 3.8.2, 3.7.5, and 3.6.7 allows remote attackers to bypass token validation. The affected invitation, OAuth, and email-verification paths hash token material with bcrypt, whose 72-byte input boundary can exclude security-relevant suffixes such as the configured invitation salt. A remote attacker who reproduces the retained prefix can modify truncated data and obtain the access conferred by the affected token flow.
Summary
What happened
Weak token hashing in Mattermost Server before 3.8.2, 3.7.5, and 3.6.7 allows remote attackers to bypass token validation. The affected invitation, OAuth, and email-verification paths hash token material with bcrypt, whose 72-byte input boundary can exclude security-relevant suffixes such as the configured invitation salt. A remote attacker who reproduces the retained prefix can modify truncated data and obtain the access conferred by the affected token flow.
The record
- CVE
- CVE-2017-18917
- Published
- Jun 19, 2020
- Updated
- Aug 5, 2024
- Vendor
- Unknown vendor
- Product
- Unknown product
- Classifications
- CWE-916, CWE-328, T1190
- Attack vector
- network
- Privileges
- unauthenticated
Timeline
How it unfolded
- Jun 19, 2020CVE publishedPublication date reported by the CVE source.
- Aug 5, 2024Record updatedLatest update available in the CVE record.
Exploitability
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What is affected?
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Published CVSS scores
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Attacks
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Technologies
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