CVE-2019-20856Network attack vector

Code execution via undisclosed dylib injection

Published Jun 19, 2020 · Updated Aug 5, 2024

Code injection in Mattermost Desktop App before 4.3.0 on macOS allows remote attackers to load a dynamic library into its process. The CNA and vendor records do not identify the component, search path, or untrusted input that permits the dylib load. NVD characterizes the path as unauthenticated and network-reachable, but public sources do not explain how remote input reaches the loader.

CVSS severity9.8
Critical
EPSS probability1.44%
Next 30 days · Sep 16, 2026
Known exploitationUnconfirmed
Based on sourced intelligence
Hinoki checkNot available
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Summary

What happened

Code injection in Mattermost Desktop App before 4.3.0 on macOS allows remote attackers to load a dynamic library into its process. The CNA and vendor records do not identify the component, search path, or untrusted input that permits the dylib load. NVD characterizes the path as unauthenticated and network-reachable, but public sources do not explain how remote input reaches the loader.

The record

CVE
CVE-2019-20856
Published
Jun 19, 2020
Updated
Aug 5, 2024
Vendor
Unknown vendor
Product
Unknown product
Classifications
CWE-427, T1574.004
Attack vector
network
Privileges
unauthenticated

Timeline

How it unfolded

  1. Jun 19, 2020CVE publishedPublication date reported by the CVE source.
  2. Aug 5, 2024Record updatedLatest update available in the CVE record.

Exploitability

Present is not the same as exploitable

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Is a vulnerable build present?

Affected buildAffected product and version details are unavailable.

What conditions does exploitation require?

Attack vectornetwork
Required privilegesunauthenticated

What is affected?

Affected products and versions are unavailable in this record.

Published CVSS scores

7.5NIST NVDAV:N/AC:L/Au:N/C:P/I:P/A:P
9.8NIST NVDCVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:H/A:H

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.

Daily unique IPsNo honeypot observations are available for this CVE in the selected window.

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-427Uncontrolled Search Path Element
T1574.004Dylib Hijacking

Public exploit references

No public exploit references are available in this record.

Labels summarize the accepted research assessment. They do not indicate a test against your environment.

Technologies

Your stack

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Your stack

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