Exploited CVEs / Samsung / CVE-2021-25487

CVE-2021-25487

Samsung Mobile Devices Out-of-Bounds Read Vulnerability. Exploitation in the wild is confirmed by CISA, not predicted. Federal agencies were required to remediate by 2023-07-20 (that deadline has passed); treat that date as the outer bound for your own environment. Check the vendor security advisory for the fix.

Risk summary

HighCISA KEV
7.8
CVSS base
<1%
EPSS exploit probability
High
Severity
2023-06-29
Added to KEV
2023-07-20 (past due)
CISA due date

Actively exploited Samsung Mobile Devices vulnerability, High severity, CVSS 7.8. Added to the CISA KEV catalog 2023-06-29.

Senserva AI read on CVE-2021-25487CISA required actionOfficial fix for CVE-2021-25487Admin questions

Senserva AI Opinion for CVE-2021-25487

Samsung mobile devices expose an out-of-bounds read in the modem interface driver, where a missing boundary check in set_skb_priv() can be leveraged into remote code execution through an invalid function pointer dereference, CVSS 7.8 (KEV, 2023-06-29). Baseband-adjacent bugs are prime material for mobile surveillance tooling, consistent with the 1% EPSS score of a targeted rather than opportunistic threat. Older Samsung handsets that stopped receiving firmware updates carry this risk indefinitely.

Do this: Enforce minimum patch-level compliance for Samsung devices in your MDM and retire handsets that no longer receive security updates.

AI-generated from public data, 2026-07-07. Verify against the vendor advisory before acting.

Senserva AI Opinion and rich prompt for CVE-2021-25487

Copy this prompt into Claude, ChatGPT, or Copilot. The facts are included, sourced from this page.

Patch now
Exploited in the wild: confirmed by the CISA KEV catalog, not predicted.
No vendor fix is mapped yet. This page refreshes daily and will name the patch the day one is published.
Do this now: Federal remediation deadline 2023-07-20; treat it as your outer bound. Patch now and verify deployment on every exposed device.

Updated August 14, 2026. Data refreshed on every build from MSRC, CISA KEV, and FIRST EPSS.

Full tracking and change history for CVE-2021-25487

Published
2023-06-29
Last revised
2023-06-29
Changes tracked
1

Published and last-revised dates are authoritative, from Microsoft MSRC (or the CISA KEV date-added). Senserva additionally records day-to-day changes from 2026-07-07, refreshed several times a day; the change count reflects that forward-only tracking.

Senserva Watchevery change we have recorded for this one
What changed, and when
  • 2023-06-29 added to the CISA KEV catalog by CISA
  • 2026-07-17 CVSS 0.0 to 7.8; EPSS first scored at 0.6%
  • 2026-07-30 EPSS 0.6% to 0.6%

Recorded by Senserva on the dates shown, from CISA KEV and FIRST EPSS. This is what moved and when, which neither the vendor advisory nor NVD publishes.

CISA required action

Federal (BOD 22-01) remediation due date: 2023-07-20 (past due).

Apply updates per vendor instructions or discontinue use of the product if updates are unavailable

Official fix for CVE-2021-25487

Check the vendor's security advisory channel for the patched Mobile Devices versions and workarounds.

CISA KEV entry

Common questions about CVE-2021-25487

Is CVE-2021-25487 actively exploited?

Yes. CVE-2021-25487 was added to the CISA Known Exploited Vulnerabilities (KEV) catalog on 2023-06-29, which means exploitation in the wild has been confirmed, not predicted. Its EPSS 30-day exploitation probability is <1%.

What is the CISA deadline and required action for CVE-2021-25487?

CISA set the federal (BOD 22-01) remediation due date at 2023-07-20, which has passed; treat any unremediated system as overdue. The verbatim required action: Apply updates per vendor instructions or discontinue use of the product if updates are unavailable

What fixes CVE-2021-25487?

Check the vendor's security advisory for the patched Mobile Devices versions and any workarounds. KEV listing makes this a fix-first item: patch it ahead of higher-CVSS issues nobody is exploiting.

Can I ask my own AI about CVE-2021-25487?

Yes. This page includes a free, ready-to-paste AI prompt containing CVE-2021-25487's key facts: severity, CVSS, EPSS, the KEV date, the CISA due date, and the required action. Copy it into Claude, ChatGPT, or Copilot; the data is refreshed twice a day (5 AM and 3 PM US Central).

Scope and sources

More exploited Samsung CVEs
CVE-2024-7399CVE-2025-21042CVE-2025-21043CVE-2025-4632CVE-2022-22265CVE-2021-25372CVE-2021-25371CVE-2021-25489

All Samsung exploited CVEs on one page: Samsung vulnerabilities actively exploited.

Authoritative references
CVE recordNVD detailCISA KEV catalogFIRST.org EPSS

Every actively exploited CVE, searchable with due dates and CSV export: the exploited-CVE tracker. The newest additions: exploited this week.

New to a term on this page? CVE, KB, KEV, CVSS, and EPSS are each explained once, on the Senserva security lexicon. Reference: Microsoft CVE and vulnerability management and the Microsoft patching guide.
Provided as is, without warranty; verify against the vendor advisory before acting. Data notice and terms.