---
id: CVE-2023-41335
aliases:
  - GHSA-4f74-84v3-j9q5
  - PYSEC-2023-185
title: >-
  matrix-synapse vulnerable to temporary storage of plaintext passwords during
  password changes
summary: >-
  matrix-synapse vulnerable to temporary storage of plaintext passwords during
  password changes
severity: low
cvss: 3.7
cvssVector: 'CVSS:3.1/AV:L/AC:H/PR:H/UI:R/S:C/C:L/I:L/A:N'
vendor: matrix-synapse
product: matrix-synapse
ecosystem: pip
affected:
  - 'matrix-synapse >= 1.66.0, < 1.93.0'
patched:
  - matrix-synapse 1.93.0
published: '2023-09-26'
updated: '2026-09-10'
sourceUpdated: '2026-09-10T03:50:03.101707044Z'
source: OSV
sourceUrl: 'https://osv.dev/vulnerability/GHSA-4f74-84v3-j9q5'
references:
  - url: >-
      https://github.com/matrix-org/synapse/security/advisories/GHSA-4f74-84v3-j9q5
  - url: 'https://nvd.nist.gov/vuln/detail/CVE-2023-41335'
  - url: 'https://github.com/matrix-org/synapse/pull/13188'
  - url: 'https://github.com/matrix-org/synapse/pull/16272'
  - url: >-
      https://github.com/matrix-org/synapse/commit/69b74d9330e42fc91a9c7423d00a06cd6d3732bf
  - url: 'https://github.com/matrix-org/synapse'
  - url: >-
      https://github.com/pypa/advisory-database/tree/main/vulns/matrix-synapse/PYSEC-2023-185.yaml
  - url: >-
      https://lists.fedoraproject.org/archives/list/package-announce@lists.fedoraproject.org/message/2AFB2Y3S2VCPCN5P2XCZTG24MBMZ7DM4
  - url: >-
      https://lists.fedoraproject.org/archives/list/package-announce@lists.fedoraproject.org/message/65QPC55I4D27HIZP7H2NQ34EOXHPP4AO
  - url: >-
      https://lists.fedoraproject.org/archives/list/package-announce@lists.fedoraproject.org/message/N6P4QULVUE254WI7XF2LWWOGHCYVFXFY
  - url: 'https://security.gentoo.org/glsa/202401-12'
tags:
  - osv
  - pip
epss: 0.00362
epssPercentile: 0.30107
ingestedAt: '2026-09-12T03:13:01.652Z'
---

## Overview

### Impact

When users update their passwords, the new credentials may be briefly held in the server database. While this doesn't grant the server any added capabilities—it already learns the users' passwords as part of the authentication process—it does disrupt the expectation that passwords won't be stored in the database. As a result, these passwords could inadvertently be captured in database backups for a longer duration.

These temporarily stored passwords are automatically erased after a 48-hour window.

### Patches
https://github.com/matrix-org/synapse/pull/16272

### References

This bug was due to a regression in https://github.com/matrix-org/synapse/pull/13188.

## Affected packages

- `matrix-synapse >= 1.66.0, < 1.93.0`

## Remediation

Upgrade to a patched release:

- `matrix-synapse 1.93.0`