Vulnerability · Published Nov 16, 2020 · Assigned by Google

CVE-2020-8897Robustness weakness in AWS KMS and Encryption SDKs

Medium 4.8

In plain English

A medium-severity security flaw in AWS SDK from Amazon. There are no confirmed reports of exploitation so far. The chance it is exploited in the next 30 days is estimated at 0.4% (higher than 34% of all known vulnerabilities). Fixed versions are available - upgrade the affected package.

Severity (CVSS 3.1)4.8Medium

Exploit odds (30 days)0.4%top 65.7% of all CVEs

Exploited in the wildNo reportsnot in CISA KEV

Attack toolingNoneno public tooling known

Official description

A weak robustness vulnerability exists in the AWS Encryption SDKs for Java, Python, C and Javalcript prior to versions 2.0.0. Due to the non-committing property of AES-GCM (and other AEAD ciphers such as AES-GCM-SIV or (X)ChaCha20Poly1305) used by the SDKs to encrypt messages, an attacker can craft a unique cyphertext which will decrypt to multiple different results, and becomes especially relevant in a multi-recipient setting. We recommend users update their SDK to 2.0.0 or later.

Affected packages & fixed versions

Ecosystem	Package	Fixed in	Advisory
Maven	com.amazonaws:aws-encryption-sdk-java	2.0.0	GHSA-wqgp-vphw-hphf
PyPI	aws-encryption-sdk	2.0.0	GHSA-wqgp-vphw-hphf
PyPI	aws-encryption-sdk	2.0.0	PYSEC-2020-261

Affected products (as reported)

Vendor	Product	Versions
Amazon	AWS SDK	stable – before 2.0.0

Weakness: CWE-310 · Vector: CVSS:3.1/AV:N/AC:H/PR:L/UI:R/S:U/C:N/I:H/A:N

References

https://github.com/google/security-research/security/advisories/GHSA-wqgp-vphw-hphf x_refsource_CONFIRM
https://aws.amazon.com/blogs/security/improved-client-side-encryption-explicit-keyids-and-key-commitment/ x_refsource_CONFIRM