Security readout for executives and security teams
Plain-English summary
CVE-2021-23335 affects the npm package is-user-valid. The reported issue is LDAP injection, which may let unauthenticated attackers bypass authentication or expose sensitive directory information in applications that use the package in reachable login or user-validation flows.
Executive priority
Treat this as a high-priority dependency risk for systems using LDAP authentication. Prioritize internet-facing or employee-login applications first, because the issue may affect authentication outcomes and confidential directory data.
Technical view
The CVE describes LDAP injection in all versions of is-user-valid. The CVSS v3.1 score is 7.5, with network access, low complexity, no privileges, and no user interaction required. The impact is rated high for confidentiality, with no integrity or availability impact recorded.
Likely exposure
Exposure is likely limited to applications that include is-user-valid and use it in LDAP-backed authentication, user validation, or directory lookup paths reachable from untrusted input.
Exploitation context
The source bundle does not identify active exploitation, and the CVE is not listed as KEV. Exploitability is still meaningful because the CVSS vector indicates remote, unauthenticated, low-complexity attack conditions.
Researcher notes
Evidence is narrow but direct: CVE and Snyk describe LDAP injection in is-user-valid with possible authentication bypass or information exposure. The bundle does not provide CWE mapping, exploit details, or a confirmed fixed version, so remediation should be tied to current vendor guidance.
Mitigation direction
- Inventory applications and lockfiles for the is-user-valid package.
- Check Snyk and package maintainer guidance for a fixed or replacement version.
- Remove or replace the dependency if no maintained fixed release is available.
- Review LDAP-backed authentication paths using the package for exposure to untrusted input.
- Add compensating monitoring for unusual authentication and directory lookup activity.
Validation and detection
- Confirm whether is-user-valid exists in production dependency trees.
- Map every reachable code path that invokes the package.
- Identify whether those paths process external username or identity fields.
- Verify LDAP-backed authentication cannot be bypassed in regression tests.
- Check logs for suspicious failed and successful login patterns.
Public sources used
Generated from the cited source records. This long-tail analysis has not been individually reviewed by a named human.
Conservative CVE-to-ATT&CK context
These mappings and lookup hints may be relevant to the vulnerability behavior, CWE, affected product, or exposure path. Glexia-inferred context is not an official MITRE, ATT&CK, CWE, or CVE Program mapping.
ATT&CK lookup starting points
Use these exact CWE pages and searches to review the Glexia ATT&CK library from this CVE's weakness and description context.
Credential and access behavior lookup
The CVE wording references authentication or credential exposure, so valid-account and credential-access review may help. This is a Glexia inferred lookup path, not an official MITRE, ATT&CK, or CVE Program mapping.
Open ATT&CK lookupCVE-2021-23335 mapping review
Open the CVE-to-ATT&CK bridge for reviewed, inferred, or future official mappings tied to this CVE.
Open ATT&CK lookup- Severity
- High
- CVSS
- 7.5 (3.1)
- Known Exploited
- No
- Published
Vector: CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:N/A:N/E:P/RL:O/RC:C
CNA and ADP enrichment extracted from CVE v5
These fields come from the CVE record and ADP containers, not from Glexia's Take. They preserve time-varying source decisions such as CISA SSVC, KEV status, CVSS metrics, and provider references.
CVSS vector scores
1 official scoreWe collect every scored CVSS vector available in the official CNA and ADP containers. When more than one version is present, the table keeps the source vectors side by side instead of collapsing them into the highest score.
CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:N/A:N/E:P/RL:O/RC:C3.93.6Primary CVE scoreVulnerability scoring details
Base CVSS 3.1 score
7.5HighVector: CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:N/A:N/E:P/RL:O/RC:C
Source materials
- CVE List V5 sourceCVE List V5
- https://snyk.io/vuln/SNYK-JS-ISUSERVALID-1056766CVE reference · x_refsource_MISC
Products and packages named in the record
CWE details
CWE links open Glexia weakness intelligence pages with official CWE context, developer remediation guidance, and related CVE mappings.