How severe is CVE-2024-29977?

CVE-2024-29977 has a CVSS 3.x base score of 2.7, rated low severity. It is exploitable over network with low attack complexity, requires high privileges and no user interaction. Impact on confidentiality is none, integrity low, and availability none.

Is CVE-2024-29977 being actively exploited?

It is not currently listed in CISA's KEV catalog. Its EPSS exploit-prediction score is 0% (19th percentile), an estimate of the probability of exploitation in the next 30 days.

What products are affected by CVE-2024-29977?

CVE-2024-29977 primarily affects Mattermost. In total, 2 product configurations (CPEs) are listed as vulnerable; see the affected-products list for the exact versions.

How do I fix CVE-2024-29977?

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

Does CVE-2024-29977 have an EU (EUVD) identifier?

Yes. CVE-2024-29977 is tracked in the ENISA EU Vulnerability Database (EUVD) as EUVD-2024-2607.

When was CVE-2024-29977 published?

CVE-2024-29977 was published on 2024-08-01 and last updated on 2026-06-17.

CVE-2024-29977

CVE-2024-29977 is a low-severity vulnerability in Mattermost with a CVSS 3.x base score of 2.7. 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-284.

Key facts

Severity: Low (CVSS 3.x base score 2.7)
EPSS exploit prediction: 0% (19th percentile)
Actively exploited: Not listed in CISA KEV
EU (EUVD) id: EUVD-2024-2607
Weakness: CWE-284
Affected product: Mattermost
Published: 2024-08-01
Last modified: 2026-06-17

Description

Mattermost versions 9.9.x <= 9.9.0, 9.5.x <= 9.5.6 fail to properly validate synced reactions, when shared channels are enabled, which allows a malicious remote to create arbitrary reactions on arbitrary posts

Frequently asked questions

What is CVE-2024-29977?: Mattermost versions 9.9.x <= 9.9.0, 9.5.x <= 9.5.6 fail to properly validate synced reactions, when shared channels are enabled, which allows a malicious remote to create arbitrary reactions on arbitrary posts
How severe is CVE-2024-29977?: CVE-2024-29977 has a CVSS 3.x base score of 2.7, rated low severity. It is exploitable over network with low attack complexity, requires high privileges and no user interaction. Impact on confidentiality is none, integrity low, and availability none.
Is CVE-2024-29977 being actively exploited?: It is not currently listed in CISA's KEV catalog. Its EPSS exploit-prediction score is 0% (19th percentile), an estimate of the probability of exploitation in the next 30 days.
What products are affected by CVE-2024-29977?: CVE-2024-29977 primarily affects Mattermost. In total, 2 product configurations (CPEs) are listed as vulnerable; see the affected-products list for the exact versions.
How do I fix CVE-2024-29977?: Review the linked vendor and NVD advisories for patched versions and mitigations, then upgrade or apply the recommended workaround.
Does CVE-2024-29977 have an EU (EUVD) identifier?: Yes. CVE-2024-29977 is tracked in the ENISA EU Vulnerability Database (EUVD) as EUVD-2024-2607.
When was CVE-2024-29977 published?: CVE-2024-29977 was published on 2024-08-01 and last updated on 2026-06-17.

References

https://mattermost.com/security-updates

Affected products (2)

cpe:2.3:a:mattermost:mattermost:*:*:*:*:*:*:*:*
cpe:2.3:a:mattermost:mattermost:9.9.0:*:*:*:*:*:*:*

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