CVE-2021-32738
Utils.readChallengeTx does not verify the server account signature
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.
Attack profile
How easy it is to exploit
- Attack vector
- Network
- Complexity
- Low
- Privileges needed
- Low
- User interaction
- None
What an attacker can affect
- Confidentiality
- None
- Integrity
- High
- Availability
- None
Exploit likelihood
What each source reports
CVE List Score used
Utils.readChallengeTx does not verify the server account signature
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.
- Record
CVE-2021-32738- CVSS 3.1
- 6.5 Medium
CVSS:3.1/AV:N/AC:L/PR:L/UI:N/S:U/C:N/I:H/A:N - Weakness
- CWE-287
- Updated
- 2026-11-02
EUVDEUVD-2021-1444
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.
- Record
EUVD-2021-1444- CVSS 3.1
- 6.5 Medium
CVSS:3.1/AV:N/AC:L/PR:L/UI:N/S:U/C:N/I:H/A:N - Updated
- 2026-11-03
GitHub AdvisoriesGHSA-6cgh-hjpw-q3gq
Utils.readChallengeTx does not verify the server account signature
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. The function does not verify that the server has signed the transaction and has been fixed so that it does in v8.2.3.
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 v8.2.3 to ensure that the challenge transaction is completely valid and signed by the server creating the challenge transaction.
- Record
GHSA-6cgh-hjpw-q3gq- CVSS 3.1
- 6.5 Medium
CVSS:3.1/AV:N/AC:L/PR:L/UI:N/S:U/C:N/I:H/A:N - Weakness
- CWE-287, CWE-347
- Updated
- 2026-11-02
NVD
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.
- Record
CVE-2021-32738- CVSS 3.1
- 6.5 Medium
CVSS:3.1/AV:N/AC:L/PR:L/UI:N/S:U/C:N/I:H/A:N - CVSS 2.0
- 4.0 Medium
AV:N/AC:L/Au:S/C:N/I:P/A:N - Weakness
- CWE-287, CWE-347
- Updated
- 2026-11-02
OSV
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.
- Record
CVE-2021-32738- CVSS 3.1
- 6.5 Medium
CVSS:3.1/AV:N/AC:L/PR:L/UI:N/S:U/C:N/I:H/A:N - Updated
- 2026-11-02
OSVGHSA-6cgh-hjpw-q3gq
Utils.readChallengeTx does not verify the server account signature
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. The function does not verify that the server has signed the transaction and has been fixed so that it does in v8.2.3.
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 v8.2.3 to ensure that the challenge transaction is completely valid and signed by the server creating the challenge transaction.
- Record
GHSA-6cgh-hjpw-q3gq- CVSS 3.1
- 6.5 Medium
CVSS:3.1/AV:N/AC:L/PR:L/UI:N/S:U/C:N/I:H/A:N - Weakness
- CWE-287, CWE-347
- Updated
- 2026-11-02
Affected products
Affected packages
| Package | Affected | Fixed |
|---|---|---|
stellar-sdknpm |
before 8.2.3 | 8.2.3 |
History
| Recorded | Changed | Sources |
|---|---|---|
| aliases | EUVD | |
| first indexed | CVE List, GitHub Advisories, NVD, OSV |
Dates are when Every CVE recorded each change. Upstream dates may differ.
In short
CVE-2021-32738 is a medium vulnerability (CVSS 6.5) in Stellar Js-stellar-sdk, published July 2, 2021. No source lists public exploit code. EPSS puts the chance of exploitation in the next 30 days at 0.51%, the 44th percentile. Fixed in stellar-sdk 8.2.3.