Utils.readChallengeTx does not verify the server account signatureGHSA-6cgh-hjpw-q3gq
MEDIUMFix: stellar/js-stellar-sdk@6f0bb88GHSA-6cgh-hjpw-q3gq is a medium-severity (CVSS 6.5) Improper Authentication vulnerability in stellar-sdk. A fix is available for stellar-sdk — see the affected versions and patch details below.
EPSS Exploitation Probability
Probability of exploitation in the next 30 days, from FIRST.org EPSS.
How urgent is this, really
GHSA-6cgh-hjpw-q3gq by exploitation likelihood (EPSS) against impact (CVSS). Outside the shaded patch-first corner.
Where this sits among everything scored
Of 385,987 CVEs with a current EPSS score, this one falls in the < 10% band (highlighted). Counts from FIRST.org, log-scaled.
Real-World Exposure
How broadly this vulnerability is actually deployed: weekly install volume shows current usage, a proxy for how much of the ecosystem is exposed.
stellar-sdknpmDescription
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.
Affected Packages
| Ecosystem | Package | Vulnerable range | Fix |
|---|---|---|---|
| 📦npm | stellar-sdk | all versions | 8.2.3npm install stellar-sdk@8.2.3 |
Affected Products
js-stellar-sdkstellarDetection & mitigation playbook
Open-source dependencyDetect
Scan your dependency tree (package-lock.json, pnpm-lock.yaml, requirements.txt, go.sum, etc.) for stellar-sdk, including transitive dependencies — a direct dependency you never call can still pull in a vulnerable version.
Fix
Update stellar-sdk to 8.2.3 or later, then make sure no transitive (indirect) dependency still pins the vulnerable range — O3 confirms GHSA-6cgh-hjpw-q3gq is resolved across your whole dependency graph.
Workarounds
Put an independent control in front of the weakness: restrict the affected endpoint or interface to trusted networks, require an additional authentication factor or proxy-level check, and invalidate existing sessions and credentials in case the flaw has already been used.
Frequently Asked Questions
Is GHSA-6cgh-hjpw-q3gq in your dependencies?
Find it across npm, including transitive dependencies.