CVE-2023-28853

Mastodon's blind LDAP injection in login allows the attacker to leak arbitrary attributes from LDAP database

MEDIUM

6.5

CVSS Score

Published: April 4, 2023 at 09:14 PM UTC

Updated: June 17, 2026 at 05:48 AM UTC

2 products affected across 2 vendorsMastodonMastodon

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Severity

MEDIUM6.5

Exploit prediction

EPSS 1%

SSVC

PoC

Description

Mastodon is a free, open-source social network server based on ActivityPub Mastodon allows configuration of LDAP for authentication. Starting in version 2.5.0 and prior to versions 3.5.8, 4.0.4, and 4.1.2, the LDAP query made during login is insecure and the attacker can perform LDAP injection attack to leak arbitrary attributes from LDAP database. This issue is fixed in versions 3.5.8, 4.0.4, and 4.1.2.

Affected

Our own answer: ranges merged, affected separated from platform-only, with confidence and review flags.

Mastodon · Joinmastodon

95%

2.5.0 ≤ v < 3.5.84.0.0 ≤ v < 4.0.44.1.0 ≤ v < 4.1.2

Affected range stops below 3.5.8, so it looks safe — our inference, not a vendor statement

Affected range stops below 4.0.4, so it looks safe — our inference, not a vendor statement

Affected range stops below 4.1.2, so it looks safe — our inference, not a vendor statement

Mastodon · Mastodon

60%

v < 3.5.8v < 4.0.4v < 4.1.2

Affected range stops below 3.5.8, so it looks safe — our inference, not a vendor statement

Affected range stops below 4.0.4, so it looks safe — our inference, not a vendor statement

Affected range stops below 4.1.2, so it looks safe — our inference, not a vendor statement

Remediation

No guide yet

No remediation guidance has been written for this CVE yet. What the record does show:

Patch and advisory references

References (8)

Source: [email protected]

http://www.openwall.com/lists/oss-security/2023/07/06/6

x_refsource_MISCProduct

Source: [email protected]

https://github.com/mastodon/mastodon/blob/94cbd808b5b3e7999c7e77dc724b7e8c9dd2bdec/app/models/concerns/ldap_authenticable.rb#L7-L14

x_refsource_MISCProduct

Source: [email protected]

https://github.com/mastodon/mastodon/blob/94cbd808b5b3e7999c7e77dc724b7e8c9dd2bdec/config/initializers/devise.rb#L398-L414

x_refsource_MISCPatch

Source: [email protected]

https://github.com/mastodon/mastodon/pull/24379

x_refsource_MISCRelease Notes

Source: [email protected]

https://github.com/mastodon/mastodon/releases/tag/v3.5.8

x_refsource_MISCRelease Notes

Source: [email protected]

https://github.com/mastodon/mastodon/releases/tag/v4.0.4

x_refsource_MISCRelease Notes

Source: [email protected]

https://github.com/mastodon/mastodon/releases/tag/v4.1.2

x_refsource_CONFIRMExploitVendor Advisory

Source: [email protected]

https://github.com/mastodon/mastodon/security/advisories/GHSA-38g9-pfm9-gfqv

SSVC — Action Prioritization

SSVCPoCNot automatablePartial impact

SSVC signals action urgency (what to patch first), separate from CVSS which measures severity.

CVSS

6.5MEDIUM[email protected]

Attack Vector: NETWORK
Complexity: LOW
Privileges: LOW
User Interaction: NONE
Scope: UNCHANGED
Confidentiality: HIGH
Integrity: NONE
Availability: NONE

Vector?

Quick Info

StatusMODIFIED

CWE

CWE-90CWE-74

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