CVE-2025-21043
Samsung Mobile Devices Out-of-Bounds Write Vulnerability
Samsung Mobile Devices
Out-of-bounds write in libimagecodec.quram.so prior to SMR Sep-2025 Release 1 allows remote attackers to execute arbitrary code.
Exploitation status
CISA Known Exploited Vulnerabilities
Listed by CISA on 2 October 2025. US federal agencies were required to remediate it by 23 October 2025.
EPSS — exploitation probability
FIRST puts the probability of exploitation activity in the next 30 days at 2.2%, which is higher than 82.7% of all scored vulnerabilities. EPSS is a forecast of activity, not a measure of severity, and it is rescored daily.
CVSS vector
CVSS:3.1/AV:N/AC:L/PR:N/UI:R/S:U/C:H/I:H/A:H
Frequently asked questions
Is CVE-2025-21043 being exploited by ransomware groups?
No ransomware group in this database is currently recorded as exploiting CVE-2025-21043.
What does CVE-2025-21043 affect?
CVE-2025-21043 affects Samsung Mobile Devices. Out-of-bounds write in libimagecodec.quram.so prior to SMR Sep-2025 Release 1 allows remote attackers to execute arbitrary code.
How severe is CVE-2025-21043?
CVE-2025-21043 is rated HIGH with a CVSS base score of 8.8. EPSS puts the probability of exploitation in the next 30 days at 2.2%, higher than 82.7% of all scored vulnerabilities. It is listed in the CISA Known Exploited Vulnerabilities catalog, with a federal remediation deadline of 23 October 2025.
How should organisations respond to CVE-2025-21043?
Apply the vendor patch for Samsung Mobile Devices as the first priority, and treat any internet-facing instance as the most urgent. Because this vulnerability is associated with ransomware activity, also review whether the affected systems were reachable before patching, rather than assuming that patching alone closes the incident.