How severe is CVE-2023-2808?

CVE-2023-2808 has a CVSS 3.x base score of 4.3, rated medium severity. It is exploitable over network with low attack complexity, requires low privileges and no user interaction. Impact on confidentiality is none, integrity low, and availability none.

Is CVE-2023-2808 being actively exploited?

It is not currently listed in CISA's KEV catalog. Its EPSS exploit-prediction score is 0% (33rd percentile), an estimate of the probability of exploitation in the next 30 days.

What products are affected by CVE-2023-2808?

CVE-2023-2808 affects Mattermost. See the affected-products list for the exact vulnerable versions.

How do I fix CVE-2023-2808?

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

When was CVE-2023-2808 published?

CVE-2023-2808 was published on 2023-05-29 and last updated on 2026-06-17.

CVE-2023-2808

CVE-2023-2808 is a medium-severity vulnerability in Mattermost with a CVSS 3.x base score of 4.3. 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-20.

Key facts

Severity: Medium (CVSS 3.x base score 4.3)
EPSS exploit prediction: 0% (33rd percentile)
Actively exploited: Not listed in CISA KEV
Weakness: CWE-20
Affected product: Mattermost
Published: 2023-05-29
Last modified: 2026-06-17

Description

Mattermost fails to normalize UTF confusable characters when determining if a preview should be generated for a hyperlink, allowing an attacker to trigger link preview on a disallowed domain using a specially crafted link.

Frequently asked questions

What is CVE-2023-2808?: Mattermost fails to normalize UTF confusable characters when determining if a preview should be generated for a hyperlink, allowing an attacker to trigger link preview on a disallowed domain using a specially crafted link.
How severe is CVE-2023-2808?: CVE-2023-2808 has a CVSS 3.x base score of 4.3, rated medium severity. It is exploitable over network with low attack complexity, requires low privileges and no user interaction. Impact on confidentiality is none, integrity low, and availability none.
Is CVE-2023-2808 being actively exploited?: It is not currently listed in CISA's KEV catalog. Its EPSS exploit-prediction score is 0% (33rd percentile), an estimate of the probability of exploitation in the next 30 days.
What products are affected by CVE-2023-2808?: CVE-2023-2808 affects Mattermost. See the affected-products list for the exact vulnerable versions.
How do I fix CVE-2023-2808?: Review the linked vendor and NVD advisories for patched versions and mitigations, then upgrade or apply the recommended workaround.
When was CVE-2023-2808 published?: CVE-2023-2808 was published on 2023-05-29 and last updated on 2026-06-17.

References

https://mattermost.com/security-updates/

Affected products (1)

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

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