Sensitive information disclosure via SNI ClientHello parsing
Published Mar 1, 2022 · Updated Oct 22, 2024
Improper input validation in FortiOS 6.4.3 and earlier allows attackers to disclose sensitive information via SNI ClientHello TLS packets. The TLS SNI ClientHello parser processes attacker-supplied packet fields without adequate validation, causing unintended sensitive-data disclosure. An attacker able to send SNI ClientHello traffic to a FortiGate processing path can obtain information; the public record does not specify authentication or configuration prerequisites.
Summary
What happened
Improper input validation in FortiOS 6.4.3 and earlier allows attackers to disclose sensitive information via SNI ClientHello TLS packets. The TLS SNI ClientHello parser processes attacker-supplied packet fields without adequate validation, causing unintended sensitive-data disclosure. An attacker able to send SNI ClientHello traffic to a FortiGate processing path can obtain information; the public record does not specify authentication or configuration prerequisites.
The record
- CVE
- CVE-2020-15936
- Published
- Mar 1, 2022
- Updated
- Oct 22, 2024
- Vendor
- Fortinet
- Product
- FortiOS
- Classifications
- CWE-20
- Attack vector
- adjacent
- Privileges
- authenticated
Timeline
How it unfolded
- Mar 1, 2022CVE publishedPublication date reported by the CVE source.
- Oct 22, 2024Record 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=FortiOS 6.4.3, 6.4.2, 6.4.1, 6.4.0, 6.2.5, 6.2.4, 6.2.3, 6.2.2, 6.2.1, 6.2.0, 6.0.11, 6.0.10, 6.0.9, 6.0.8, 6.0.7, 6.0.6, 6.0.5, 6.0.4, 6.0.3, 6.0.2, 6.0.1, 6.0.0, 5.6.13, 5.6.12, 5.6.11, 5.6.10, 5.6.9, 5.6.8, 5.6.7, 5.6.6, 5.6.5, 5.6.4, 5.6.3, 5.6.2, 5.6.1, 5.6.0
What conditions does exploitation require?
What is affected?
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
No public exploit references are available in this record.
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Technologies
Your stack
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Your stack
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