CVE-2022-39380Network attack vector

Chat-history denial of service via malformed Markdown

Published Jan 27, 2023 · Updated Mar 10, 2025

Improper exception handling in Wire Web App before 2022-11-02 allows remote attackers to block display of a conversation's chat history. The Markdown-to-HTML conversion path throws an unhandled error for certain formatting combinations and repeats the failure whenever history retrieval includes the malformed message. A crafted message must enter a conversation; the failure prevents rendering only that conversation's affected history and leaves other conversations available.

CVSS severity5.3
Medium
EPSS probability0.62%
Next 30 days · Sep 16, 2026
Known exploitationUnconfirmed
Based on sourced intelligence
Hinoki checkNot available
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Summary

What happened

Improper exception handling in Wire Web App before 2022-11-02 allows remote attackers to block display of a conversation's chat history. The Markdown-to-HTML conversion path throws an unhandled error for certain formatting combinations and repeats the failure whenever history retrieval includes the malformed message. A crafted message must enter a conversation; the failure prevents rendering only that conversation's affected history and leaves other conversations available.

The record

CVE
CVE-2022-39380
Published
Jan 27, 2023
Updated
Mar 10, 2025
Vendor
Wire Swiss GmbH
Product
Wire Web App
Classifications
CWE-755, T1499
Attack vector
network
Privileges
unauthenticated

Timeline

How it unfolded

  1. Jan 27, 2023CVE publishedPublication date reported by the CVE source.
  2. Mar 10, 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=< 2022-11-02

What conditions does exploitation require?

Attack vectornetwork
Required privilegesunauthenticated

What is affected?

Wire Swiss GmbH · Wire Web Appversion=< 2022-11-02

Published CVSS scores

5.3GitHub, Inc.CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:L

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 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-755Improper Handling of Exceptional Conditions
T1499Endpoint Denial of Service

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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