Kernel read and write via DPU use-after-free
Published Mar 26, 2021 · Updated Jan 14, 2026
Use-after-free in the DPU driver in Samsung Mobile Devices before SMR Mar-2021 Release 1 allows local users to read and write kernel memory. The decon_set_win_config function installs a fence file descriptor before decon_create_release_fences can release the underlying file object, leaving open descriptors that reference freed memory. The observed exploit chain ran from an application on Exynos-based phones using kernel 4.14.113 and turned the dangling file object into arbitrary kernel read and write access.
Summary
What happened
Use-after-free in the DPU driver in Samsung Mobile Devices before SMR Mar-2021 Release 1 allows local users to read and write kernel memory. The decon_set_win_config function installs a fence file descriptor before decon_create_release_fences can release the underlying file object, leaving open descriptors that reference freed memory. The observed exploit chain ran from an application on Exynos-based phones using kernel 4.14.113 and turned the dangling file object into arbitrary kernel read and write access.
The record
- CVE
- CVE-2021-25370
- Published
- Mar 26, 2021
- Updated
- Jan 14, 2026
- Vendor
- Samsung Electronics Co., Ltd.
- Product
- Samsung Mobile Devices
- Classifications
- CWE-703, CWE-416, T1068
- Attack vector
- local
- Privileges
- Unavailable
Timeline
How it unfolded
- Mar 26, 2021CVE publishedPublication date reported by the CVE source.
- Jan 14, 2026Record updatedLatest update available in the CVE record.
Exploitability
Present is not the same as exploitable
Compare your product and version with the public record. A matching version still requires validation against your environment.
Is a vulnerable build present?
Compare these published version ranges with your installed build and any vendor patches.
- Affected versionversion=Selected O(8.X), P(9.0), Q(10.0), R(11.0) <SMR Mar-2021 Release 1
What conditions does exploitation require?
What is affected?
Published CVSS scores
CVSS describes severity. EPSS estimates exploitation probability.
Attacks
What attackers are doing with it
Daily unique IPs observed by Shadowserver honeypots for known exploited vulnerabilities (KEVs). Missing observations do not establish an absence of attacks.
Weakness, pattern, technique
Public exploit references
No public exploit references are available in this record.
Labels summarize the accepted research assessment. They do not indicate a test against your environment.
Reported exploitation
- Late-2020 Samsung exploit chainexploit chain
- CISA Known Exploited Vulnerabilities Catalog entryknown exploited catalog
Technologies
Your stack
See the directory against your own environment.
Your stack
Check the software in your environment
Book a demo to see how Hinoki identifies affected software and validates exploitability in your environment.
Book a demo