CVE-2021-25487 Samsung Mobile Devices Out-of-Bounds Read Vulnerability
Samsung mobile devices contain an out-of-bounds read vulnerability within the modem interface driver due to a lack of boundary checking of a buffer in set_skb_priv(), leading to remote code execution by dereference of an invalid function pointer.
From the CISA KEV catalogue version 2026.11.06, with Cybergen analysis. Updated 6 Nov 2026.
Should You Worry?
- CISA confirmed exploitation in the wild and added it to the Known Exploited Vulnerabilities catalogue on 29 Jun 2023.
- Rated High severity (CVSS 7.3, scored by Vendor).
- It has been in the catalogue for 1,226 days. Systems still unpatched now have almost certainly been scanned for it.
What It Is
Lack of boundary checking of a buffer in set_skb_priv() of modem interface driver prior to SMR Oct-2021 Release 1 allows OOB read and it results in arbitrary code execution by dereference of invalid function pointer.
Affected Versions
| Product | Versions |
|---|---|
| Samsung Mobile Samsung Mobile Devices | O(8.1), P(9.0), Q(10.0), R(11.0) to before SMR Oct-2021 Release 1 |
From the public CVE record, as supplied by the vendor. Always confirm against the vendor advisory.
What To Do Now
- 1
Find it
Search your asset inventory and external attack surface for Samsung Mobile Devices. Include cloud images, appliances and anything a supplier runs for you.
Attack Surface Management - 2
Fix it
Apply updates per vendor instructions or discontinue use of the product if updates are unavailable
Vulnerability Management - 3
Hunt for compromise
If an affected system was reachable before you patched, assume it may have been hit. Check logs, new accounts, web shells and outbound connections from the date of exposure.
Incident Response - 4
Prove it is fixed
Rescan or test the system after patching. Upgrades that fail silently and forgotten secondary instances are common.
Penetration Testing
The Compliance Clock
General guidance, not legal advice. Your obligations depend on your sector, scope and jurisdiction.
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