Exynos 980 FirmwareOperating system · Samsung

CVE-2025-27891

CRITICAL · 9.1 CVSS v3.1 Published 2025-05-14
Mitigation only
No fix yet — a mitigation exists. There is no fixed release. A documented workaround reduces exposure in the meantime.
See remediation →
100/100
Remediation priority · Urgent
Remotely reachable No privileges Zero-click

Official description Straight from the sourceThe vendor's or NVD's own wording, published unedited. Authoritative, but often terse — it says what broke, rarely what to do.

NVD · unedited
An issue was discovered in Samsung Mobile Processor, Wearable Processor, and Modem Exynos 980, 990, 850, 1080, 2100, 1280, 2200, 1330, 1380, 1480, 2400, W920, W930, W1000, Modem 5123, Modem 5300, Modem 5400. The lack of a length check leads to out-of-bounds reads via malformed NAS packets.

Technical summary Written by usOur analysis, written from the advisory, the CVSS vector and the affected-version data. It adds context the advisory leaves out, and never invents facts that are not in the source.

dbcve analysis · high confidence

A missing length check in the NAS (Non-Access Stratum) protocol handling of Samsung Exynos mobile and wearable processors and modems allows out-of-bounds memory reads when processing malformed NAS packets. This memory safety vulnerability affects 15 processor variants and 3 modem variants, enabling potential information disclosure or further exploitation.

MitigationApply Samsung firmware/security updates for affected processors and modems once released by the vendor; prioritize mobile devices with direct internet exposure.

Verify against the referenced sources before acting — the references below are authoritative for this CVE, this summary is not.

Affected products & versions What the vendor confirmedThe version ranges the vendor confirmed as vulnerable. If your version sits inside a range here, treat yourself as exposed until you have upgraded.

NVD · CPE data
Exynos 980 FirmwareOperating system
Affected:all versions
Exynos 990 FirmwareOperating system
Affected:all versions
Exynos 850 FirmwareOperating system
Affected:all versions
Exynos 1080 FirmwareOperating system
Affected:all versions
Exynos 2100 FirmwareOperating system
Affected:all versions
Exynos 1280 FirmwareOperating system
Affected:all versions
Exynos 2200 FirmwareOperating system
Affected:all versions
Exynos 1330 FirmwareOperating system
Affected:all versions

CVSS breakdown How the score is builtThe industry scoring standard. It rates how the flaw is reached, what it takes to exploit, and what an attacker gains — the score is derived from those, not the other way round.

From the vector
Attack vector
Network
Complexity
Low
Privileges
None
User interaction
None
Scope
Unchanged
Confidentiality
High
Integrity
None
Availability
High

CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:N/A:H

Am I affected? How to checkSteps we derive from the advisory and the affected-version data, so you can decide whether this CVE reaches your setup. They are a guide, not a scan — your own configuration is the authority.

dbcve checks

Work through these to decide whether this CVE applies to you.

  1. Identify the Exynos processor model
    On the target device, check the processor/CPU information via Settings > About Phone > Processor or by examining /proc/cpuinfo for 'Exynos' entries, or use a system information app
    Affected if The processor model matches one of the affected variants: Exynos 980, 990, 850, 1080, 2100, 1280, 2200, or 1330
  2. Confirm firmware version
    Check the baseband/modem firmware version via Settings > About Phone > Baseband version, or use *#0011# on the dialer for service mode, or examine /proc/version
    Affected if The device runs any firmware version on the affected Exynos processors (all versions listed as affected)
  3. Verify cellular/mobile connectivity capability
    Confirm the device has cellular modem capability by checking for SIM card slots, mobile network settings, and baseband information presence in system settings
    Affected if The device has an active cellular radio and NAS (Non-Access Stratum) protocol stack is present and processing mobile network packets
  4. Check for vendor security updates
    Review Settings > Software Update or Security Patch level in Settings > About Phone to determine the installed Samsung security patch date
    Affected if The security patch level predates the vendor release addressing CVE-2025-27891, or the device is no longer receiving updates

A device is affected if it contains any of the following Exynos processors (980, 990, 850, 1080, 2100, 1280, 2200, 1330) with cellular capability and lacks the vendor security update addressing this vulnerability.

Generated from the published advisory. Verify against your own configuration.

Check your environment

Paste your version and any relevant configuration and it will be compared against the affected criteria above. Do not include secrets or credentials.

AI-assisted, checked against the advisory. Informational, not a guarantee.

Remediation Closing itWhat it takes to close this. Where a vendor fix exists we point at it; where none exists we say so plainly, and can build one. Effort estimates are scoped from the advisory, not from your codebase.

From vendor data
Mitigation available No clean upgrade yet — mitigate in the meantime
Mitigation

Apply Samsung firmware/security updates for affected processors and modems once released by the vendor; prioritize mobile devices with direct internet exposure.

Fix this in Exynos 980 Firmware Scoped from the published advisory
  • Consultation8.0 h
  • Implementation16.0 h
  • Testing12.0 h
  • Review / QA8.0 h
44.0 hours of engineering $7,720
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Scan for this in your stack

Free · runs locally
dbcve dependency scanner

Check whether your project pulls in CVE-2025-27891 — or any other known-vulnerable package — straight from your lock files. Free and open source; it runs locally and uploads nothing.

References Go to the primary sourcePrimary sources — vendor advisories, patches and trackers. Where our summary and a reference disagree, the reference wins.

Primary sources

Practitioner notes

Contributed

Peer-ranked notes from engineers who’ve handled CVE-2025-27891 in production — separate from our analysis above.

No notes yet

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What this is

A place for practitioners to share what actually worked: a mitigation you’ve tested, a configuration change, a version- or environment-specific caveat, or a link to a verified patch. The most useful notes rise to the top as peers upvote them, so the signal stays high.

What belongs here
  • Verified mitigations, workarounds, and config changes
  • Version or environment caveats, and links to real fixes
  • No weaponised exploit code, or anything meant to cause harm
  • No spam, self-promotion, credentials, or personal data