Vulnerability in Amazon AWS Cloud Development Kit
CVE-2025-23206
The AWS Cloud Development Kit (AWS CDK) is an open-source software development framework to define cloud infrastructure in code and provision it through AWS CloudFormation. Users who use IAM OIDC custom resource provider package will download CA Thumbprints as part of the custom resource workflow. However, the current `tls.connect` method will always set `rejectUnauthorized: false` which is a potential security concern. CDK should follow the best practice and set `rejectUnauthorized: true`. However, this could be a breaking change for existing CDK applications and we should fix this with a feature flag. Note that this is marked as low severity Security advisory because the issuer url is provided by CDK users who define the CDK application. If they insist on connecting to a unauthorized OIDC provider, CDK should not disallow this. Additionally, the code block is run in a Lambda environment which mitigate the MITM attack. The patch is in progress. To mitigate, upgrade to CDK v2.177.0 (Expected release date 2025-02-22). Once upgraded, users should make sure the feature flag '@aws-cdk/aws-iam:oidcRejectUnauthorizedConnections' is set to true in `cdk.context.json` or `cdk.json`. There are no known workarounds for this vulnerability.
Published · last modified .
CVSS v3 metric
CVSS v3 base score 8.1 (High). Vector: CVSS:3.1/AV:N/AC:L/PR:L/UI:N/S:U/C:H/I:H/A:N.
EPSS exploit prediction
EPSS: 0.003 (23.3th percentile), scored .
Very low probability of exploitation in the next 30 days; routine patching cadence is appropriate. 23rd percentile — 23.3% of CVEs in the catalogue have a lower EPSS than this one. How to read EPSS.
EPSS over last 30 days · oldest: 0.003 · newest: 0.003 · change: 0.000
Affected products
- Amazon AWS Cloud Development Kit
- AWS Aws-Cdk — versions < 2.177.0
Weakness classification (CWE)
Public proof-of-concept exploits
References
- github.com/aws/aws-cdk/security/advisories/GHSA-v4mq-x674-ff73 (Vendor Advisory)
- github.com/aws/aws-cdk/issues/32920 (Issue Tracking)
- github.com/aws/aws-cdk/pull/32921
- github.com/aws/aws-cdk/commit/3e4f3773bfa48b75bf0adc7d53d46bbec7714a9e
- docs.aws.amazon.com/cdk/v2/guide/featureflags.html
- github.com/aws/aws-cdk/blob/d16482fc8a4a3e1f62751f481b770c09034df7d2/packages/@… (Product)
- github.com/aws/aws-cdk/releases/tag/v2.177.0
Frequently asked questions
- What is CVE-2025-23206?
- CVE-2025-23206 is a high-severity vulnerability in Amazon AWS Cloud Development Kit, classified under Improper Verification of Cryptographic Signature. CVSS score: 8.1/10. Published 2025-01-17.
- How severe is CVE-2025-23206?
- High severity. CVSS v3 base score is 8.1 out of 10.
- Is CVE-2025-23206 known to be exploited?
- 1 public proof-of-concept repositories are indexed. Not currently listed in the CISA KEV catalog.