CVE-2020-8897
HIGHSecurity issues in AWS KMS and AWS Encryption SDKs: in-band protocol negotiation and robustness
EPSS Exploitation Probability
EPSS (Exploit Prediction Scoring System) is a daily probability model maintained by FIRST.org. It estimates the likelihood a CVE will be exploited in production environments within the next 30 days, derived from real-world threat intelligence signals.
Blast Radius
com.amazonaws:aws-encryption-sdk-java🐍aws-encryption-sdkReal-time download stats are indexed for npm and PyPI packages. This vulnerability affects Maven, PyPI packages — download data is not available via public APIs for these ecosystems.
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
| Ecosystem | Package | Vulnerable range | Fix |
|---|---|---|---|
| ☕Maven | com.amazonaws:aws-encryption-sdk-java | all versions | 2.0.0 |
| 🐍PyPI | aws-encryption-sdk | all versions | 2.0.0 |
Research use only. For defensive security, authorized penetration testing, and academic research only. Never execute exploit code against systems without explicit written authorization.
Detection & mitigation playbook
Open-source dependencyDetect
Scan your dependency tree (package-lock.json, pnpm-lock.yaml, requirements.txt, go.sum, etc.) for com.amazonaws:aws-encryption-sdk-java. O3's reachability analysis confirms whether the vulnerable code path is actually invoked in your application, so you act on real exposure instead of every transitive match.
Fix
Update com.amazonaws:aws-encryption-sdk-java to 2.0.0 or later, then make sure no transitive (indirect) dependency still pins the vulnerable range — O3 confirms CVE-2020-8897 is resolved across your whole dependency graph.
Workarounds
If you can't upgrade right away: gate or disable the affected feature, validate untrusted input at the boundary, and avoid passing attacker-controlled data into the vulnerable path. O3's runtime protection blocks exploitation in production as an interim safeguard until the upgrade lands.
How O3 protects you
O3 pinpoints whether CVE-2020-8897 is reachable in your code and exactly where to fix it, then blocks exploitation in production at runtime until the patched version is deployed.
Tailored to CVE-2020-8897. Runtime protection reduces exposure until a permanent patch is applied and verified — it complements patching, it doesn't replace it.
Frequently Asked Questions
Is CVE-2020-8897 in your dependencies?
O3 detects CVE-2020-8897 across Maven, PyPI dependencies and uses function-level reachability to confirm whether the vulnerable code path is actually reachable — not just present. No false positives.