---
id: "CVE-2021-25487"
kind: "vulnerability"
aliases: ["CVE-2021-25487"]
title: "samsung android: Lack of boundary checking of a buffer in set_skb_priv() of modem interface driver prior to SMR Oct-2021 Release 1\u2026"
severity: "critical"
cvss: 7.8
epss: null
exploited: true
status: "open"
category: "vendor"
products: [{"name": "Samsung Mobile Devices", "fixed": [], "affected": "", "ecosystem": "vendor"}, {"name": "samsung android", "fixed": [], "affected": "= 8.1", "ecosystem": "vendor"}, {"name": "samsung android", "fixed": [], "affected": "= 9.0", "ecosystem": "vendor"}, {"name": "samsung android", "fixed": [], "affected": "= 10.0", "ecosystem": "vendor"}, {"name": "samsung android", "fixed": [], "affected": "= 11.0", "ecosystem": "vendor"}]
ecosystems: ["vendor"]
tags: ["android", "exploited", "mobile-devices", "samsung", "vendor"]
not_affected_if: ["non-samsung-devices"]
published_at: "2021-10-06T18:15:09+00:00"
first_seen_at: "2026-10-23T19:11:51+00:00"
updated_at: "2026-10-23T22:29:04+00:00"
sources: [{"source": "kev", "url": "https://www.cisa.gov/known-exploited-vulnerabilities-catalog?search_api_fulltext=CVE-2021-25487", "first_seen_at": "2026-10-23T19:11:51+00:00"}, {"source": "nvd", "url": "https://nvd.nist.gov/vuln/detail/CVE-2021-25487", "first_seen_at": "2026-10-23T22:29:04+00:00"}]
---

# samsung android: Lack of boundary checking of a buffer in set_skb_priv() of modem interface driver prior to SMR Oct-2021 Release 1…

Samsung mobile devices have an out-of-bounds read in the modem interface driver, caused by missing boundary checks on a buffer in set_skb_priv(). The sources say an attacker can get remote code execution by triggering a dereference of an invalid function pointer.

_Summary, check and fix written by a model from the sources; labelled as such._

## Affected

- vendor:Samsung Mobile Devices affected ? fixed ?
- vendor:samsung android affected = 8.1 fixed ?
- vendor:samsung android affected = 9.0 fixed ?
- vendor:samsung android affected = 10.0 fixed ?
- vendor:samsung android affected = 11.0 fixed ?

## How to check

Check the Android security patch level on each device (Settings > About phone > Software information); the sources do not name the patched level.

## Fix

Apply the Samsung security update that covers this flaw, per vendor instructions; if no update is available, stop using the affected device.

## Timeline

- 2026-10-23T19:11:51+00:00 kev https://www.cisa.gov/known-exploited-vulnerabilities-catalog?search_api_fulltext=CVE-2021-25487
- 2026-10-23T22:29:04+00:00 nvd https://nvd.nist.gov/vuln/detail/CVE-2021-25487

## From the sources

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.

CISA required action: Apply updates per vendor instructions or discontinue use of the product if updates are unavailable

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