Vulnerability Details : CVE-2020-8912
A vulnerability in the in-band key negotiation exists in the AWS S3 Crypto SDK for GoLang versions prior to V2. An attacker with write access to the targeted bucket can change the encryption algorithm of an object in the bucket, which can then allow them to change AES-GCM to AES-CTR. Using this in combination with a decryption oracle can reveal the authentication key used by AES-GCM as decrypting the GMAC tag leaves the authentication key recoverable as an algebraic equation. It is recommended to update your SDK to V2 or later, and re-encrypt your files.
Exploit prediction scoring system (EPSS) score for CVE-2020-8912
Probability of exploitation activity in the next 30 days: 0.04%
Percentile, the proportion of vulnerabilities that are scored at or less: ~ 11 % EPSS Score History EPSS FAQ
CVSS scores for CVE-2020-8912
Base Score | Base Severity | CVSS Vector | Exploitability Score | Impact Score | Score Source |
---|---|---|---|---|---|
2.1
|
LOW | AV:L/AC:L/Au:N/C:P/I:N/A:N |
3.9
|
2.9
|
NIST |
2.5
|
LOW | CVSS:3.1/AV:L/AC:H/PR:L/UI:N/S:U/C:L/I:N/A:N |
1.0
|
1.4
|
Google Inc. |
2.5
|
LOW | CVSS:3.1/AV:L/AC:H/PR:L/UI:N/S:U/C:L/I:N/A:N |
1.0
|
1.4
|
NIST |
CWE ids for CVE-2020-8912
-
The product uses a broken or risky cryptographic algorithm or protocol.Assigned by:
- cve-coordination@google.com (Secondary)
- nvd@nist.gov (Primary)
References for CVE-2020-8912
-
https://github.com/google/security-research/security/advisories/GHSA-7f33-f4f5-xwgw
In-band key negotiation issue in AWS S3 Crypto SDK for golang · Advisory · google/security-research · GitHubExploit;Third Party Advisory
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https://aws.amazon.com/blogs/developer/updates-to-the-amazon-s3-encryption-client/?s=09
Updates to the Amazon S3 Encryption Client | AWS Developer BlogVendor Advisory
Products affected by CVE-2020-8912
- cpe:2.3:a:amazon:aws_s3_crypto_sdk:*:*:*:*:*:golang:*:*