Server impersonation via skipped TLS hostname check
Published Jul 12, 2021 · Updated Aug 4, 2024
Improper TLS certificate validation in Fossil before 2.14.2 and 2.15.x before 2.15.2 allows man-in-the-middle attackers to impersonate servers. The client-side SSL setup in src/http_ssl.c accepts any otherwise valid certificate without checking whether its hostname matches the requested server. An attacker able to intercept an HTTPS connection can substitute a valid certificate for another host and tamper with repository traffic.
Summary
What happened
Improper TLS certificate validation in Fossil before 2.14.2 and 2.15.x before 2.15.2 allows man-in-the-middle attackers to impersonate servers. The client-side SSL setup in src/http_ssl.c accepts any otherwise valid certificate without checking whether its hostname matches the requested server. An attacker able to intercept an HTTPS connection can substitute a valid certificate for another host and tamper with repository traffic.
The record
- CVE
- CVE-2021-36377
- Published
- Jul 12, 2021
- Updated
- Aug 4, 2024
- Vendor
- Unknown vendor
- Product
- Unknown product
- Classifications
- CWE-295, T1557
- Attack vector
- network
- Privileges
- unauthenticated
Timeline
How it unfolded
- Jul 12, 2021CVE publishedPublication date reported by the CVE source.
- Aug 4, 2024Record updatedLatest update available in the CVE record.
Exploitability
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What is affected?
Affected products and versions are unavailable in this record.
Attacks
What attackers are doing with it
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Public exploit references
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Technologies
Your stack
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Your stack
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