Client crash via authenticated length underflow
Published May 10, 2021 · Updated Aug 3, 2024
Integer overflow in Yubico YubiHSM 2 SDK 2.0.3 and earlier allows attackers to crash client software via an authenticated device reply. In _send_secure_msg(), an eight-byte response lets the session ID overlap the MAC, then two subtractions wrap a 16-bit length to 65,535 and pass it to OpenSSL CBC decryption. Exploitation requires a malicious HSM or man-in-the-middle attackers with session secrets; the affected client process then crashes reliably.
Summary
What happened
Integer overflow in Yubico YubiHSM 2 SDK 2.0.3 and earlier allows attackers to crash client software via an authenticated device reply. In _send_secure_msg(), an eight-byte response lets the session ID overlap the MAC, then two subtractions wrap a 16-bit length to 65,535 and pass it to OpenSSL CBC decryption. Exploitation requires a malicious HSM or man-in-the-middle attackers with session secrets; the affected client process then crashes reliably.
The record
- CVE
- CVE-2021-32489
- Published
- May 10, 2021
- Updated
- Aug 3, 2024
- Vendor
- Unknown vendor
- Product
- Unknown product
- Classifications
- CWE-190, T1499.004
- Attack vector
- network
- Privileges
- authenticated
Timeline
How it unfolded
- May 10, 2021CVE publishedPublication date reported by the CVE source.
- Aug 3, 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.
Weakness, pattern, technique
Public exploit references
- CVE-2021-32489 malicious-response simulation patchproof of concept · demonstrated
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Technologies
Your stack
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Your stack
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