CVE-2026-21091 — Android
HIGHCVE-2026-21091 is a high-severity (CVSS 7.8) Out-of-bounds Write vulnerability in samsung android. No vendor fix is recorded yet; mitigation options are listed below.
Out-of-bounds write in libcodec2secevrcdec.so prior to SMR Sep-2026 Release 1 allows local attackers to write out-of-bounds memory.
Exploitation Status
No confirmed exploitation observed yet
- CISA’s own triage has not observed active exploitation or public proof-of-concept code for this CVE as of its last assessment.
Exploitation and automatability from CISA’s SSVC triage for CVE-2026-21091.
EPSS Exploitation Probability
Probability of exploitation in the next 30 days, from FIRST.org EPSS.
How urgent is this, really
CVE-2026-21091 by exploitation likelihood (EPSS) against impact (CVSS). Outside the shaded patch-first corner.
Where this sits among everything scored
Of 385,987 CVEs with a current EPSS score, this one falls in the < 10% band (highlighted). Counts from FIRST.org, log-scaled.
Description
Out-of-bounds write in libcodec2secevrcdec.so prior to SMR Sep-2026 Release 1 allows local attackers to write out-of-bounds memory.
Affected Products
androidsamsungDetection & mitigation playbook
Vendor / applianceDetect
Inventory every samsung android deployment and check each version against the affected-products list above.
Remediation status
No patch has shipped for CVE-2026-21091 yet — track the samsung android advisory for a fixed release and apply the workarounds below in the meantime.
Mitigate without a patch
Stop feeding it untrusted input: reject or quarantine files and payloads from unverified sources until you can upgrade, restrict accepted formats to the ones you actually need, and run the parsing or decoding step in a least-privileged sandbox or short-lived worker so a crash or corrupted read cannot reach the rest of the process. Alongside that, restrict the management interface to trusted networks and apply the vendor's recommended configuration mitigations.
Frequently Asked Questions
Is CVE-2026-21091 being exploited in your environment?
Detect and block the exploit chain at execution, on systems you cannot patch yet.