CVE-2021-23335Network attack vector

Authentication bypass via LDAP injection

Published Feb 11, 2021 · Updated Sep 16, 2024

LDAP injection in is-user-valid all versions allows remote attackers to bypass authentication or expose LDAP information via crafted email input. The CNA and vendor records disclose LDAP injection but do not identify the request handler, query construction, or escaping operation that creates it. The service is reachable over the network without authentication; impact is limited to authentication bypass or directory-information exposure, with no reported integrity or availability effect.

CVSS severity7.5
High
EPSS probability1.42%
Next 30 days · Sep 16, 2026
Known exploitationUnconfirmed
Based on sourced intelligence
Hinoki checkNot available
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Summary

What happened

LDAP injection in is-user-valid all versions allows remote attackers to bypass authentication or expose LDAP information via crafted email input. The CNA and vendor records disclose LDAP injection but do not identify the request handler, query construction, or escaping operation that creates it. The service is reachable over the network without authentication; impact is limited to authentication bypass or directory-information exposure, with no reported integrity or availability effect.

The record

CVE
CVE-2021-23335
Published
Feb 11, 2021
Updated
Sep 16, 2024
Vendor
is-user-valid Project
Product
is-user-valid
Classifications
CWE-90, CWE-74, T1190
Attack vector
network
Privileges
unauthenticated

Timeline

How it unfolded

  1. Feb 11, 2021CVE publishedPublication date reported by the CVE source.
  2. Sep 16, 2024Record updatedLatest update available in the CVE record.

Exploitability

Present is not the same as exploitable

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Is a vulnerable build present?

Compare these published version ranges with your installed build and any vendor patches.

  1. Affected versionversion=0 <unspecified

What conditions does exploitation require?

Attack vectornetwork
Required privilegesunauthenticated

What is affected?

is-user-valid Project · is-user-validversion=0 <unspecified

Published CVSS scores

5.0NVDAV:N/AC:L/Au:N/C:P/I:N/A:N
7.5SnykCVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:N/A:N

CVSS describes severity. EPSS estimates exploitation probability.

Attacks

What attackers are doing with it

Daily unique IPs observed by Shadowserver honeypots for known exploited vulnerabilities (KEVs). Missing observations do not establish an absence of attacks.

Daily unique IPsNo honeypot observations are available for this CVE in the selected window.

No observations available

Sep 10, 2026Sep 16, 2026
Latest reporting daySep 16, 2026
Latest daily unique IPsUnavailable
Prior 30-day averageUnavailable
SourceShadowserver honeypots (KEV)
Vectornetwork
Privilegesunauthenticated
Known exploitationUnconfirmed
Public exploitUnconfirmed

Weakness, pattern, technique

CWE-90Improper Neutralization of Special Elements in LDAP Query ('LDAP Injection')
CWE-74Improper Neutralization of Special Elements in Output Used by a Downstream Component ('Injection')
T1190Exploit Public-Facing Application

Public exploit references

No public exploit references are available in this record.

Labels summarize the accepted research assessment. They do not indicate a test against your environment.

Technologies

Your stack

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Your stack

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