CVE-2019-20875Network attack vector

Unauthenticated password reset during concurrent email changes

Published Jun 19, 2020 · Updated Aug 5, 2024

Improper authentication in Mattermost Server before 5.9.0, 5.8.1, 5.7.3, and 4.10.8 allows remote attackers to reset a password. The public record states that password-reset processing can complete concurrently with an email-address change, but Mattermost has not disclosed the faulty function or validation step. The reset endpoint requires no authentication; successful use changes an account credential without reported confidentiality or availability impact.

CVSS severity5.3
Medium
EPSS probability0.77%
Next 30 days · Sep 16, 2026
Known exploitationUnconfirmed
Based on sourced intelligence
Hinoki checkNot available
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Summary

What happened

Improper authentication in Mattermost Server before 5.9.0, 5.8.1, 5.7.3, and 4.10.8 allows remote attackers to reset a password. The public record states that password-reset processing can complete concurrently with an email-address change, but Mattermost has not disclosed the faulty function or validation step. The reset endpoint requires no authentication; successful use changes an account credential without reported confidentiality or availability impact.

The record

CVE
CVE-2019-20875
Published
Jun 19, 2020
Updated
Aug 5, 2024
Vendor
Unknown vendor
Product
Unknown product
Classifications
CWE-287, T1098
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

5.3NIST NVDCVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:L/A:N
5.0NIST NVDAV:N/AC:L/Au:N/C:N/I:P/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.

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-287Improper Authentication
T1098Account Manipulation

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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