TLS endpoint impersonation via negative return coercion
Published Feb 27, 2020 · Updated Aug 4, 2024
Certificate validation bypass in lua-openssl 0.7.7-1 allows man-in-the-middle attackers to impersonate TLS endpoints. openssl_x509_check_host passes X509_check_host's -1 error return to lua_pushboolean, which converts the nonzero value to true and accepts an invalid certificate regardless of hostname. Exploitation requires control of the connection path and a client that relies on this binding, exposing intercepted traffic to reading or modification.
Summary
What happened
Certificate validation bypass in lua-openssl 0.7.7-1 allows man-in-the-middle attackers to impersonate TLS endpoints. openssl_x509_check_host passes X509_check_host's -1 error return to lua_pushboolean, which converts the nonzero value to true and accepts an invalid certificate regardless of hostname. Exploitation requires control of the connection path and a client that relies on this binding, exposing intercepted traffic to reading or modification.
The record
- CVE
- CVE-2020-9432
- Published
- Feb 27, 2020
- Updated
- Aug 4, 2024
- Vendor
- Unknown vendor
- Product
- Unknown product
- Classifications
- CWE-295, T1557
- Attack vector
- network
- Privileges
- unauthenticated
Timeline
How it unfolded
- Feb 27, 2020CVE publishedPublication date reported by the CVE source.
- Aug 4, 2024Record updatedLatest update available in the CVE record.
Exploitability
Present is not the same as exploitable
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What conditions does exploitation require?
What is affected?
Affected products and versions are unavailable in this record.
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.
Public exploit references
- Invalid X.509 certificate proof of conceptproof of concept · demonstrated
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Technologies
Your stack
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Your stack
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