{"id":"CVE-2024-1402","aliases":["GHSA-32h7-7j94-8fc2","BIT-mattermost-2024-1402","GO-2024-2541"],"title":"Mattermost vulnerable to denial of service via large number of emoji reactions","summary":"Mattermost vulnerable to denial of service via large number of emoji reactions","severity":"medium","cvss":4.3,"cvssVector":"CVSS:3.1/AV:N/AC:L/PR:L/UI:N/S:U/C:N/I:N/A:L","vendor":"mattermost","product":"github.com/mattermost/mattermost/server/v8","ecosystem":"go","affected":["github.com/mattermost/mattermost/server/v8 < 8.1.8","github.com/mattermost/mattermost/server/v8 >= 9.2.0, < 9.2.4","github.com/mattermost/mattermost/server/v8 >= 9.1.0, < 9.1.5"],"patched":["github.com/mattermost/mattermost/server/v8 8.1.8","github.com/mattermost/mattermost/server/v8 9.2.4","github.com/mattermost/mattermost/server/v8 9.1.5"],"published":"2024-02-09","updated":"2026-09-10","sourceUpdated":"2026-09-10T03:50:05.197770614Z","source":"OSV","sourceUrl":"https://osv.dev/vulnerability/GHSA-32h7-7j94-8fc2","references":[{"url":"https://nvd.nist.gov/vuln/detail/CVE-2024-1402"},{"url":"https://github.com/mattermost/mattermost/commit/64cb0ca8af2dbda1afcddd1604460591a4799b81"},{"url":"https://github.com/mattermost/mattermost/commit/6d2440de9fd774b67e65e3aac4ab8b6ef9aba2d8"},{"url":"https://github.com/mattermost/mattermost/commit/81190e2da128a6985914ea7023a69ac400513fc4"},{"url":"https://github.com/mattermost/mattermost"},{"url":"https://mattermost.com/security-updates"}],"tags":["osv","go"],"epss":0.00524,"epssPercentile":0.43244,"ingestedAt":"2026-09-12T03:13:01.747Z","slug":"CVE-2024-1402","body":"## Overview\n\nMattermost fails to check if a custom emoji reaction exists when sending it to a post and to limit the amount of custom emojis allowed to be added in a post, allowing an attacker sending a huge amount of non-existent custom emojis in a post to crash the mobile app of a user seeing the post. Fetching posts with huge amounts of reactions results in Uncontrolled Resource Consumption.\n\n## Affected packages\n\n- `github.com/mattermost/mattermost/server/v8 < 8.1.8`\n- `github.com/mattermost/mattermost/server/v8 >= 9.2.0, < 9.2.4`\n- `github.com/mattermost/mattermost/server/v8 >= 9.1.0, < 9.1.5`\n\n## Remediation\n\nUpgrade to a patched release:\n\n- `github.com/mattermost/mattermost/server/v8 8.1.8`\n- `github.com/mattermost/mattermost/server/v8 9.2.4`\n- `github.com/mattermost/mattermost/server/v8 9.1.5`","depth":"sunlit","depthScore":24,"depthScoreParts":{"impact":23.7,"likelihood":0.1,"exploitation":0,"ransomware":0},"changes":[]}