CVE-2020-8911
Vulnerability from cvelistv5
Published
2020-08-11 19:20
Modified
2024-08-04 10:12
Severity ?
5.6 (Medium) - CVSS:3.1/AV:L/AC:H/PR:L/UI:N/S:C/C:H/I:N/A:N
Summary
A padding oracle vulnerability exists in the AWS S3 Crypto SDK for GoLang versions prior to V2. The SDK allows users to encrypt files with AES-CBC without computing a Message Authentication Code (MAC), which then allows an attacker who has write access to the target's S3 bucket and can observe whether or not an endpoint with access to the key can decrypt a file, they can reconstruct the plaintext with (on average) 128*length (plaintext) queries to the endpoint, by exploiting CBC's ability to manipulate the bytes of the next block and PKCS5 padding errors. It is recommended to update your SDK to V2 or later, and re-encrypt your files.
References
cve-coordination@google.comhttps://aws.amazon.com/blogs/developer/updates-to-the-amazon-s3-encryption-client/?s=09Vendor Advisory
cve-coordination@google.comhttps://github.com/google/security-research/security/advisories/GHSA-f5pg-7wfw-84q9Exploit, Third Party Advisory
af854a3a-2127-422b-91ae-364da2661108https://aws.amazon.com/blogs/developer/updates-to-the-amazon-s3-encryption-client/?s=09Vendor Advisory
af854a3a-2127-422b-91ae-364da2661108https://github.com/google/security-research/security/advisories/GHSA-f5pg-7wfw-84q9Exploit, Third Party Advisory
Impacted products
Vendor Product Version
Show details on NVD website

To clipboard 

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