How severe is CVE-2023-3591?

CVE-2023-3591 has a CVSS 3.x base score of 4.8, rated medium severity. It is exploitable over network with high attack complexity, requires no privileges and no user interaction. Impact on confidentiality is low, integrity low, and availability none.

Is CVE-2023-3591 being actively exploited?

It is not currently listed in CISA's KEV catalog. Its EPSS exploit-prediction score is 0% (21st percentile), an estimate of the probability of exploitation in the next 30 days.

What products are affected by CVE-2023-3591?

CVE-2023-3591 affects Mattermost Mattermost Server. See the affected-products list for the exact vulnerable versions.

How do I fix CVE-2023-3591?

Review the linked vendor and NVD advisories for patched versions and mitigations, then upgrade or apply the recommended workaround.

When was CVE-2023-3591 published?

CVE-2023-3591 was published on 2023-07-17 and last updated on 2026-06-17.

CVE-2023-3591

CVE-2023-3591 is a medium-severity vulnerability in Mattermost Mattermost Server with a CVSS 3.x base score of 4.8. It is not currently listed as actively exploited by CISA, and its EPSS exploit-prediction score is low. The underlying weakness is classified as CWE-287.

Key facts

Severity: Medium (CVSS 3.x base score 4.8)
EPSS exploit prediction: 0% (21st percentile)
Actively exploited: Not listed in CISA KEV
Weakness: CWE-287
Affected product: Mattermost Mattermost Server
Published: 2023-07-17
Last modified: 2026-06-17

Description

Mattermost fails to invalidate previously generated password reset tokens when a new reset token was created.

Frequently asked questions

What is CVE-2023-3591?: Mattermost fails to invalidate previously generated password reset tokens when a new reset token was created.
How severe is CVE-2023-3591?: CVE-2023-3591 has a CVSS 3.x base score of 4.8, rated medium severity. It is exploitable over network with high attack complexity, requires no privileges and no user interaction. Impact on confidentiality is low, integrity low, and availability none.
Is CVE-2023-3591 being actively exploited?: It is not currently listed in CISA's KEV catalog. Its EPSS exploit-prediction score is 0% (21st percentile), an estimate of the probability of exploitation in the next 30 days.
What products are affected by CVE-2023-3591?: CVE-2023-3591 affects Mattermost Mattermost Server. See the affected-products list for the exact vulnerable versions.
How do I fix CVE-2023-3591?: Review the linked vendor and NVD advisories for patched versions and mitigations, then upgrade or apply the recommended workaround.
When was CVE-2023-3591 published?: CVE-2023-3591 was published on 2023-07-17 and last updated on 2026-06-17.

References

https://mattermost.com/security-updates

Affected products (1)

cpe:2.3:a:mattermost:mattermost_server:*:*:*:*:*:*:*:*

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