How severe is CVE-2021-46823?

CVE-2021-46823 has a CVSS 3.x base score of 6.5, rated medium severity. It is exploitable over network with low attack complexity, requires low privileges and no user interaction. Impact on confidentiality is none, integrity none, and availability high.

Is CVE-2021-46823 being actively exploited?

It is not currently listed in CISA's KEV catalog. Its EPSS exploit-prediction score is 2% (75th percentile), an estimate of the probability of exploitation in the next 30 days.

What products are affected by CVE-2021-46823?

CVE-2021-46823 affects Python-ldap. See the affected-products list for the exact vulnerable versions.

How do I fix CVE-2021-46823?

Review the linked vendor and NVD advisories for patched versions and mitigations, then upgrade or apply the recommended workaround.

When was CVE-2021-46823 published?

CVE-2021-46823 was published on 2022-06-18 and last updated on 2026-06-17.

CVE-2021-46823

CVE-2021-46823 is a medium-severity vulnerability in Python-ldap with a CVSS 3.x base score of 6.5. It is not currently listed as actively exploited by CISA, and its EPSS exploit-prediction score is low. The underlying weakness is classified as CWE-1333.

Key facts

Severity: Medium (CVSS 3.x base score 6.5)
CVSS v2: 4.0
EPSS exploit prediction: 2% (75th percentile)
Actively exploited: Not listed in CISA KEV
Weakness: CWE-1333
Affected product: Python-ldap
Published: 2022-06-18
Last modified: 2026-06-17

Description

python-ldap before 3.4.0 is vulnerable to a denial of service when ldap.schema is used for untrusted schema definitions, because of a regular expression denial of service (ReDoS) flaw in the LDAP schema parser. By sending crafted regex input, a remote authenticated attacker could exploit this vulnerability to cause a denial of service condition.

Frequently asked questions

What is CVE-2021-46823?: python-ldap before 3.4.0 is vulnerable to a denial of service when ldap.schema is used for untrusted schema definitions, because of a regular expression denial of service (ReDoS) flaw in the LDAP schema parser. By sending crafted regex input, a remote authenticated attacker could exploit this vulnerability to cause a denial of service condition.
How severe is CVE-2021-46823?: CVE-2021-46823 has a CVSS 3.x base score of 6.5, rated medium severity. It is exploitable over network with low attack complexity, requires low privileges and no user interaction. Impact on confidentiality is none, integrity none, and availability high.
Is CVE-2021-46823 being actively exploited?: It is not currently listed in CISA's KEV catalog. Its EPSS exploit-prediction score is 2% (75th percentile), an estimate of the probability of exploitation in the next 30 days.
What products are affected by CVE-2021-46823?: CVE-2021-46823 affects Python-ldap. See the affected-products list for the exact vulnerable versions.
How do I fix CVE-2021-46823?: Review the linked vendor and NVD advisories for patched versions and mitigations, then upgrade or apply the recommended workaround.
When was CVE-2021-46823 published?: CVE-2021-46823 was published on 2022-06-18 and last updated on 2026-06-17.

References

Affected products (1)

cpe:2.3:a:python-ldap:python-ldap:*:*:*:*:*:*:*:*

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