Vulnerability · Published Aug 11, 2020 · Assigned by Google
CVE-2020-8912In-band key negotiation issue in AWS S3 Crypto SDK for GoLang
Low 2.5
In plain English
A low-severity broken cryptography in AWS S3 Crypto SDK for GoLang from Google LLC. There are no confirmed reports of exploitation so far. The chance it is exploited in the next 30 days is estimated at 0.2% (higher than 14% of all known vulnerabilities). Fixed versions are available - upgrade the affected package.
Official description
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.
Affected packages & fixed versions
| Ecosystem | Package | Fixed in | Advisory |
|---|---|---|---|
| Go | github.com/aws/aws-sdk-go | 1.34.0 | GHSA-7f33-f4f5-xwgw |
| Go | github.com/aws/aws-sdk-go | no fix listed | GO-2022-0635 |
Affected products (as reported)
| Vendor | Product | Versions |
|---|---|---|
| Google LLC | AWS S3 Crypto SDK for GoLang | stable – through V1 |
Weakness: CWE-327 · Vector: CVSS:3.1/AV:L/AC:H/PR:L/UI:N/S:U/C:L/I:N/A:N