Medium severity · published Oct 17, 2023
CVE-2023-5522
Mobile app freezes when receiving a post with hundreds of emojis
4.3
CVSS
0.4%
EPSS
No
On KEV
Description
Mattermost Mobile fails to limit the maximum number of Markdown elements in a post allowing an attacker to send a post with hundreds of emojis to a channel and freeze the mobile app of users when viewing that particular channel.
CVSS vector
CVSS:3.1/AV:N/AC:L/PR:N/UI:R/S:U/C:N/I:N/A:L
Attack vector
Network
Complexity
Low
Privileges
None
User interaction
Required
Confidentiality
None
Integrity
None
Availability
Low
Scope
Unchanged
Exploitation
Is it being used?
Exploit prediction (EPSS)0.4% · higher than 38% of CVEs
Exploited in the wildNo evidence yet
CISA KEVNot listed
Ransomware campaign useNot known
Affected products
Which versions
MA
Mattermost · Mattermost
before 2.8.0 · source: vendor, NVD
References
NVD
https://nvd.nist.gov/vuln/detail/CVE-2023-5522
CVE.org
https://www.cve.org/CVERecord?id=CVE-2023-5522
Vendor Advisory
https://mattermost.com/security-updates
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