Auth bypass in Stellar Js-Stellar-Sdk
CVE-2021-32738
js-stellar-sdk is a Javascript library for communicating with a Stellar Horizon server. The `Utils.readChallengeTx` function used in SEP-10 Stellar Web Authentication states in its function documentation that it reads and validates the challenge transaction including verifying that the `serverAccountID` has signed the transaction. In js-stellar-sdk before version 8.2.3, the function does not verify that the server has signed the transaction. Applications that also used `Utils.verifyChallengeTxThreshold` or `Utils.verifyChallengeTxSigners` to verify the signatures including the server signature on the challenge transaction are unaffected as those functions verify the server signed the transaction. Applications calling `Utils.readChallengeTx` should update to version 8.2.3, the first version with a patch for this vulnerability, to ensure that the challenge transaction is completely valid and signed by the server creating the challenge transaction.
Vulnerability class: Broken Authentication
Published · last modified .
CVSS v3 metric
CVSS v3 base score 6.5 (Medium). Vector: CVSS:3.1/AV:N/AC:L/PR:L/UI:N/S:U/C:N/I:H/A:N.
EPSS exploit prediction
EPSS: 0.005 (41.4th percentile), scored .
Very low probability of exploitation in the next 30 days; routine patching cadence is appropriate. 41st percentile — 41.4% of CVEs in the catalogue have a lower EPSS than this one. How to read EPSS.
EPSS over last 30 days · oldest: 0.005 · newest: 0.005 · change: 0.000
Affected products
- Stellar Js-Stellar-Sdk — versions < 8.2.3
Weakness classification (CWE)
References
- github.com/stellar/js-stellar-sdk/security/advisories/GHSA-6cgh-hjpw-q3gq (Third Party Advisory)
- github.com/stellar/js-stellar-sdk/releases/tag/v8.2.3 (Third Party Advisory, Release Notes)
Frequently asked questions
- What is CVE-2021-32738?
- CVE-2021-32738 is a medium-severity vulnerability in Stellar Js-Stellar-Sdk, classified under Improper Authentication. CVSS score: 6.5/10. Published 2021-07-02.
- How severe is CVE-2021-32738?
- Medium severity. CVSS v3 base score is 6.5 out of 10.