CVE-2022-35923
Inefficient Regular Expression Complexity in v8n
v8n is a javascript validation library. Versions of v8n prior to 1.5.1 were found to have an inefficient regular expression complexity in the lowercase() and uppercase() regex which could lead to a denial of service attack. In testing of the lowercase() function a payload of 'a' + 'a'.repeat(i) + 'A' with 32 leading characters took 29443 ms to execute. The same issue happens with uppercase(). Users are advised to upgrade. There are no known workarounds for this issue.
Attack profile
How easy it is to exploit
- Attack vector
- Network
- Complexity
- Low
- Privileges needed
- None
- User interaction
- None
What an attacker can affect
- Confidentiality
- None
- Integrity
- None
- Availability
- High
Exploit likelihood
What each source reports
CVE List Score used
Inefficient Regular Expression Complexity in v8n
v8n is a javascript validation library. Versions of v8n prior to 1.5.1 were found to have an inefficient regular expression complexity in the lowercase() and uppercase() regex which could lead to a denial of service attack. In testing of the lowercase() function a payload of 'a' + 'a'.repeat(i) + 'A' with 32 leading characters took 29443 ms to execute. The same issue happens with uppercase(). Users are advised to upgrade. There are no known workarounds for this issue.
- Record
CVE-2022-35923- CVSS 3.1
- 7.5 High
CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:H - Weakness
- CWE-400
- Updated
- 2026-11-02
EUVDEUVD-2022-7187
v8n is a javascript validation library. Versions of v8n prior to 1.5.1 were found to have an inefficient regular expression complexity in the lowercase() and uppercase() regex which could lead to a denial of service attack. In testing of the lowercase() function a payload of 'a' + 'a'.repeat(i) + 'A' with 32 leading characters took 29443 ms to execute. The same issue happens with uppercase(). Users are advised to upgrade. There are no known workarounds for this issue.
- Record
EUVD-2022-7187- CVSS 3.1
- 7.5 High
CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:H - Updated
- 2026-11-02
GitHub AdvisoriesGHSA-xrx9-gj26-5wx9
v8n vulnerable to Inefficient Regular Expression Complexity
Impact
Inefficient regular expression complexity of lowercase() and uppercase() regex could lead to a denial of service attack. With a formed payload 'a' + 'a'.repeat(i) + 'A', only 32 characters payload could take 29443 ms time execution when testing lowercase(). The same issue happens with uppercase().
Patches
v1.5.1
References
huntr.dev report Regular Expression Denial of Service (ReDoS) and Catastrophic Backtracking
For more information
If you have any questions or comments about this advisory:
- Open an issue in v8n issues list
- Email us at [email protected]
- Record
GHSA-xrx9-gj26-5wx9- CVSS 3.1
- 7.5 High
CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:H - Weakness
- CWE-400, CWE-1333
- Updated
- 2026-11-02
NVD
v8n is a javascript validation library. Versions of v8n prior to 1.5.1 were found to have an inefficient regular expression complexity in the lowercase() and uppercase() regex which could lead to a denial of service attack. In testing of the lowercase() function a payload of 'a' + 'a'.repeat(i) + 'A' with 32 leading characters took 29443 ms to execute. The same issue happens with uppercase(). Users are advised to upgrade. There are no known workarounds for this issue.
- Record
CVE-2022-35923- CVSS 3.1
- 7.5 High
CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:H - Weakness
- CWE-400, CWE-1333
- Updated
- 2026-11-02
OSV
Inefficient Regular Expression Complexity in v8n
v8n is a javascript validation library. Versions of v8n prior to 1.5.1 were found to have an inefficient regular expression complexity in the lowercase() and uppercase() regex which could lead to a denial of service attack. In testing of the lowercase() function a payload of 'a' + 'a'.repeat(i) + 'A' with 32 leading characters took 29443 ms to execute. The same issue happens with uppercase(). Users are advised to upgrade. There are no known workarounds for this issue.
- Record
CVE-2022-35923- CVSS 3.1
- 7.5 High
CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:H - Weakness
- CWE-400
- Updated
- 2026-11-02
OSVGHSA-xrx9-gj26-5wx9
v8n vulnerable to Inefficient Regular Expression Complexity
Impact
Inefficient regular expression complexity of lowercase() and uppercase() regex could lead to a denial of service attack. With a formed payload 'a' + 'a'.repeat(i) + 'A', only 32 characters payload could take 29443 ms time execution when testing lowercase(). The same issue happens with uppercase().
Patches
v1.5.1
References
huntr.dev report Regular Expression Denial of Service (ReDoS) and Catastrophic Backtracking
For more information
If you have any questions or comments about this advisory:
- Open an issue in v8n issues list
- Email us at [email protected]
- Record
GHSA-xrx9-gj26-5wx9- CVSS 3.1
- 7.5 High
CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:H - Weakness
- CWE-1333, CWE-400
- Updated
- 2026-11-02
Affected products
Affected packages
| Package | Affected | Fixed |
|---|---|---|
v8nnpm |
before 1.5.1 | 1.5.1 |
History
| Recorded | Changed | Sources |
|---|---|---|
| first indexed | CVE List, EUVD, GitHub Advisories, NVD, OSV |
Dates are when Every CVE recorded each change. Upstream dates may differ.
In short
CVE-2022-35923 is a high vulnerability (CVSS 7.5) in Imbrn V8n, published August 2, 2022. No source lists public exploit code. EPSS puts the chance of exploitation in the next 30 days at 1.76%, the 78th percentile. Fixed in v8n 1.5.1.
References
github.com/imbrn/v8n/security/advisories/GHSA-xrx9-gj26-5wx9
huntr.dev/bounties/2d92f644-593b-43b4-bfd1-c8042ac60609
nvd.nist.gov/vuln/detail/CVE-2022-35923