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Threats / Samsung / CVE-2021-25394
CVE-2021-25394 · EUVD no mirror located · GCVE no mirror located Verified 2026-08-04

Samsung Mobile Devices vulnerability

Samsung mobile devices contain a use-after-free vulnerability in the MFC charger driver triggered by a race condition. Exploitation requires prior radio privilege compromise and enables arbitrary memory writes.

Verdict

Today item — known-exploited.

A race condition in Samsung's MFC charger driver creates a use-after-free condition exploitable by attackers with radio-layer access, permitting memory corruption and potential privilege escalation or code execution on affected mobile devices.

CISA KEV Yes · 2023-06-295EPSS 0.00401 (verify live)6CVSS 6.43CISA SSVC Exploitation: active · Automatable: no · Impact: total4
01

Is it exploitable?

— the evidence, ranked above the score
Reported exploitation
3 independent public reports of in-the-wild exploitation are cataloged.Distinct reporting sources (vendor, incident response, government); open them for the underlying claims.
Exploited in the wild
Listed in the CISA Known Exploited Vulnerabilities catalog (added 2023-06-29).
CISA KEV ↗Confirmed
Probability (EPSS)
EPSS 0.00401 — modeled likelihood of exploitation activity.EPSS is a daily-changing model output — open the source for today's value.
Severity / affected
CVSS 6.4 (CVSS:3.1/AV:L/AC:H/PR:H/UI:N/S:U/C:H/I:H/A:H) · Affected: Samsung, Mobile Devices. Confirm exact fixed builds in the vendor advisory.CVSS — CNA-assigned (CVE.org), version 3.1, set at disclosure.
CVE.org ↗Reported
Weakness (CWE)
Mapped to CWE-416 Use After Free — weakness family: Memory safety.CWE — CNA-assigned (CVE.org); the weakness class drives how the flaw is exploited.
CVE.org ↗Reported
CISA SSVC (triage disposition)
Exploitation: active · Automatable: no · Technical Impact: totalCISA's own stakeholder-specific triage inputs, published in the CVE record (CISA Coordinator role). NOTE: this is CISA's three decision points; the final Act/Attend/Track decision also requires a Mission & Well-being input not published here, so no overall decision is asserted.
CISA-ADP ↗Reported
Currency of the record
CISA added this to its KEV catalog 748 days after the CVE record was published.KEV lag = CISA-KEV dateAdded − CVE.org datePublished; a floor on how long the known-exploited flaw sat in the public record before the federal catalog listed it. Severity/weakness here is CNA- or CISA-assigned (current at disclosure), independent of NVD's analysis backlog.
WeaknessCWE-416 · Use After FreeMemory safety
02

Who’s exploiting it?

— attribution turns risk into urgency
Attribution not established

No confirmed (advisory-backed) threat-actor attribution is established for this record. Absence of a named actor is not absence of compromise — see Coverage & confidence.

03

Why it matters

— the attack path, told twice: adversary, then board
1

Front door — unauthenticated access narrative 1

Attacker
I compromise the radio baseband processor or modem firmware to gain radio privilege on the target device.
Business
The device's cellular and wireless communications layer becomes a foothold for further system compromise.
2

Keys to the kingdom — privilege/identity takeover narrative 2

Attacker
I trigger a race condition in the MFC charger driver by timing concurrent operations to cause a use-after-free condition.
Business
Memory safety controls are bypassed, exposing the kernel to corruption and control-flow hijacking.
3

Lateral reach — past segmentation narrative 3

Attacker
I write to freed memory regions to corrupt kernel data structures or inject executable code.
Business
The attacker gains kernel-level code execution, enabling full device compromise, data exfiltration, and persistent malware installation.
04

What to do

— defensible action
  • Remediate per the vendor advisory — confirm the fixed build for your version and verify exposure.1
Say it to the boardA vulnerability with this evidence profile is a defensible budget line, not a backlog ticket — fund the change against the proof above.
05

Coverage & confidence

— what we know, and what we don’t

Established (cited)

  • KEV listing (CISA)
  • EPSS probability (FIRST)
  • 3 reported-exploitation source(s)
  • CVSS 6.4 — CNA-assigned (CVE.org)
  • CISA SSVC triage disposition (CVE.org ADP)
  • CWE weakness mapping — CNA-assigned (CVE.org)
  • Catalogued by Samsung Mobile (CNA)
  • Coverage gaps — stated, not hidden

  • No EUVD / GCVE mirror in feed — single-authority dependency for the identifier.
  • EPSS & exposure are time-varying; verify live at the source.
  • Threat-actor attribution not established from feed data — absence of a name is not absence of compromise.
  • No finder/reporter credit recorded in the public CVE entry — the work behind this find is unattributed.
  • Disclosure & credit2
    Catalogued by Samsung MobileCNA
    Credited with finding itNo finder named in the public CVE record — the work behind this find is unattributed.