# CVE-2020-8897: Security issues in AWS KMS and AWS Encryption SDKs: in-band protocol negotiation and robustness

Source: https://junglewise.ai/threats/cve-2020-8897-security-issues-in-aws-kms-and-aws-encryption-sdks-in-band  
Publisher: Junglewise Threat Intelligence, https://junglewise.ai/threats  
Published: 2020-11-16  
License: CC BY 4.0 with a link back

CVE-2020-8897 · Severity: low · CVSS 3.1 · Published 2020-11-16

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.

Technologies: [com.amazonaws:aws-encryption-sdk-java (Maven)](https://junglewise.ai/threats/technologies/com-amazonaws-aws-encryption-sdk-java), [aws-encryption-sdk (PyPI)](https://junglewise.ai/threats/technologies/aws-encryption-sdk). Vendors: [Maven](https://junglewise.ai/threats/vendors/maven), [PyPI](https://junglewise.ai/threats/vendors/pypi).

## Quick answers

**Is CVE-2020-8897 exploited in the wild?** No. Junglewise Threat Intelligence has no report of CVE-2020-8897 being exploited in the wild.

**How severe is CVE-2020-8897?** Low severity, with a CVSS score of 3.1, published 16 November 2020.

**Which products and versions are affected?** com.amazonaws:aws-encryption-sdk-java (Maven) ECOSYSTEM:introduced=0,fixed=2.0.0; aws-encryption-sdk (PyPI) ECOSYSTEM:introduced=0,fixed=2.0.0.

**Is there a fix for CVE-2020-8897?** Yes. com.amazonaws:aws-encryption-sdk-java (Maven): upgrade to 2.0.0 or later; aws-encryption-sdk (PyPI): upgrade to 2.0.0 or later. Junglewise finds every place you run it, drafts the upgrade and applies it once you approve.

**Am I affected by CVE-2020-8897?** Check whether you run com.amazonaws:aws-encryption-sdk-java (Maven) or aws-encryption-sdk (PyPI) at an affected version. Junglewise does that check for you around the clock: connect your code, cloud and domains, and it matches new vulnerabilities like this one against what you actually run and tells you when one reaches you.

## How to fix

- com.amazonaws:aws-encryption-sdk-java (Maven): upgrade to 2.0.0 or later

  ```sh
  # set com.amazonaws:aws-encryption-sdk-java to 2.0.0 in your pom.xml or build.gradle
  ```

- aws-encryption-sdk (PyPI): upgrade to 2.0.0 or later

  ```sh
  pip install "aws-encryption-sdk>=2.0.0"
  ```


## Affected products

- com.amazonaws:aws-encryption-sdk-java (Maven) ECOSYSTEM:introduced=0,fixed=2.0.0
- aws-encryption-sdk (PyPI) ECOSYSTEM:introduced=0,fixed=2.0.0

## Identifiers

- CVE-2020-8897
- GHSA-wqgp-vphw-hphf
- PYSEC-2020-261

## Related threats

- [Cryptographic algorithm downgrade in the caching layer of Amazon AWS Encryption SDK for Python before version 3.3.1 and before version 4.0.](https://junglewise.ai/threats/cve-2026-6550-aws-encryption-sdk-for-python-key-commitment-policy-bypass-via)
- [Duplicate Advisory: Improper Verification of Cryptographic Signature in aws-encryption-sdk-java](https://junglewise.ai/threats/duplicate-advisory-improper-verification-of-cryptographic-signature-in-1a00970e)
- [Improper Verification of Cryptographic Signature in aws-encryption-sdk](https://junglewise.ai/threats/improper-verification-of-cryptographic-signature-in-aws-encryption-sdk-b9344234)
- [Improper Verification of Cryptographic Signature in aws-encryption-sdk-java](https://junglewise.ai/threats/cve-2024-23680-improper-verification-of-cryptographic-signature-in-aws)