CVE-2023-41335

Password disclosure via UI authentication database persistence

Published Sep 26, 2023 · Updated Feb 13, 2025

Cleartext password storage in Matrix.org Synapse 1.66.0 through 1.92.3 allows local users to read new passwords from the database. The password-change handler passes the new_password field into user-interactive authentication, which serializes it in the ui_auth_sessions.clientdict database column. Exposure requires a password change plus privileged database or backup access; retained plaintext is purged within 48 hours.

CVSS severity3.7
Low
EPSS probability0.36%
Next 30 days · Sep 16, 2026
Known exploitationUnconfirmed
Based on sourced intelligence
Hinoki checkNot available
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Summary

What happened

Cleartext password storage in Matrix.org Synapse 1.66.0 through 1.92.3 allows local users to read new passwords from the database. The password-change handler passes the new_password field into user-interactive authentication, which serializes it in the ui_auth_sessions.clientdict database column. Exposure requires a password change plus privileged database or backup access; retained plaintext is purged within 48 hours.

The record

CVE
CVE-2023-41335
Published
Sep 26, 2023
Updated
Feb 13, 2025
Vendor
Matrix.org
Product
Synapse
Classifications
CWE-312, T1005
Attack vector
local
Privileges
admin

Timeline

How it unfolded

  1. Sep 26, 2023CVE publishedPublication date reported by the CVE source.
  2. Feb 13, 2025Record 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=>= 1.66.0, < 1.93.0

What conditions does exploitation require?

Attack vectorlocal
Required privilegesadmin

What is affected?

Matrix.org · Synapseversion=>= 1.66.0, < 1.93.0

Published CVSS scores

3.7NIST NVDCVSS:3.1/AV:N/AC:H/PR:L/UI:R/S:U/C:L/I:L/A:N
3.7GitHub, Inc.CVSS:3.1/AV:L/AC:H/PR:H/UI:R/S:C/C:L/I:L/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.

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No observations available

Sep 9, 2026Sep 15, 2026
Latest reporting daySep 15, 2026
Latest daily unique IPsUnavailable
Prior 30-day averageUnavailable
SourceShadowserver honeypots (KEV)
Vectorlocal
Privilegesadmin
Known exploitationUnconfirmed
Public exploitUnconfirmed

Weakness, pattern, technique

CWE-312Cleartext Storage of Sensitive Information
T1005Data from Local System

Public exploit references

No public exploit references are available in this record.

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Technologies

Your stack

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Your stack

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