CVE-2020-8897 Robustness weakness in AWS KMS and Encryption SDKs
Attackers can craft ciphertexts that decrypt to multiple results due to non-committing AEAD ciphers, impacting data integrity in multi-recipient scenarios.
- Exploited in the wild
- Not known
- Login needed
- Any signed-in user
- Attackable
- Over the internet
- Victim action needed
- A user has to click or open something
- Fix
- Available
What is CVE-2020-8897?
CVE-2020-8897 is a medium-severity vulnerability in Amazon AWS SDK, published on 16 Nov 2020. Any signed-in user can exploit it over the network, and only if a user opens a file or follows a link.
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.
Which versions are affected by CVE-2020-8897?
5 open source packages ship an affected version, including com.amazonaws:aws-encryption-sdk-java and aws-encryption-sdk. It affects 1 product.
| Package | Affected | Fixed in |
|---|---|---|
com.amazonaws:aws-encryption-sdk-java Maven | All versions | 2.0.0 |
com.amazonaws:aws-encryption-sdk-java Maven | All versions | 2.0.0 |
aws-encryption-sdk PyPI | All versions | 2.0.0 |
aws-encryption-sdk PyPI | All versions | 2.0.0 |
aws-encryption-sdk PyPI | All versions | 2.0.0 |
Products include Amazon Aws Encryption Sdk.
How do I fix CVE-2020-8897?
Upgrade com.amazonaws:aws-encryption-sdk-java to 2.0.0 or later.
Is CVE-2020-8897 being exploited?
There is no known exploitation of CVE-2020-8897 in the wild and no public exploit code.
Other vulnerabilities in Amazon AWS SDK
Sources
Also known as GHSA-wqgp-vphw-hphf, PYSEC-2020-261.