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
Arm C1-Ultra, C1-Premium, Neoverse V3 & V3AE, Neoverse V2, Neoverse V1, Neoverse-N2, Neoverse-N1, Cortex-X925, Cortex-X4, Cortex-X3, Cortex-X2, Cortex-X1 & X1C, Cortex-A710, Cortex-A78, A78AE & A78C, Cortex-A77, Cortex-A76 & A76A may allow writes to resources owned by a higher exception level.
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 · moderate confidence
A vulnerability in multiple Arm processor cores allows code executing at a lower exception level (EL0/EL1) to write to memory resources owned by a higher exception level (EL2/EL3), potentially enabling privilege escalation to more privileged software execution levels.
MitigationApply processor firmware/microcode updates provided by Arm and system-on-chip vendors. For affected systems where updates are unavailable, implement compensating controls such as restricting untrusted code execution and monitoring for privilege escalation indicators.
Verify against the referenced sources before acting — the references below are authoritative for this CVE, this summary is not.
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
High
Availability
None
CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:H/A:N
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.
Identify your Arm processor model
On the target system, run `cat /proc/cpuinfo` or use `lscpu` to display processor information. Look for the processor name, model number, and architecture version (e.g., ARMv8, ARMv9).
Affected if The system uses an Arm processor where lower Exception Levels can improperly access higher-level resources. If you cannot determine your exact processor model, assume potential exposure.
Check Arm processor firmware version
Retrieve the firmware or System-on-Chip (SoC) firmware version using vendor-specific tools (e.g., `dmidecode` on some systems, or check `/sys/firmware/` entries). Consult your hardware vendor documentation for the exact command to query firmware revision.
Affected if The firmware version is older than the latest microcode/firmware update released by Arm and your OEM for this CVE. If no firmware version is reported or obtainable, treat the system as potentially affected.
Determine if the system is virtualized
Run commands such as `systemd-detect-virt`, `virt-what`, or check for hypervisor signatures in `/proc/cpuinfo` (e.g., 'Hypervisor' field). Identify whether a hypervisor (KVM, Xen, VMware, etc.) is present.
Affected if The system runs as a virtual machine on an Arm hypervisor. In virtualized environments, the hypervisor must enforce proper Exception Level boundaries to prevent guest VM escape.
Verify hypervisor Exception Level configuration
If a hypervisor is in use, check its configuration and version using vendor-specific commands (e.g., `xl version`, `virsh version`, or hypervisor management console). Confirm the hypervisor enforces EL2/EL3 separation and has applied CVE-related updates.
Affected if The hypervisor version predates the CVE fix or does not implement proper Exception Level boundary enforcement between VMs and the hypervisor layer.
Check for EL3/EL2 boundary enforcement
On systems with secure monitor access, verify that the secure monitor (EL3) and hypervisor (EL2) are configured to restrict lower-EL access to protected resources. This typically requires checking secure boot state, Trusted Execution Environment (TEE) configuration, or consulting vendor documentation.
Affected if The system does not enforce strict Exception Level separation, allowing code at EL0-EL2 to write to resources intended only for EL3 or higher.
A system is affected if it runs on an Arm processor where firmware is unpatched, or if a hypervisor does not enforce proper Exception Level boundaries, allowing privilege escalation from lower to higher Exception Levels.
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 availableNo clean upgrade yet — mitigate in the meantime
Mitigation
Apply processor firmware/microcode updates provided by Arm and system-on-chip vendors. For affected systems where updates are unavailable, implement compensating controls such as restricting untrusted code execution and monitoring for privilege escalation indicators.
Have this fixed
Scoped from the published advisory
An estimate, not a bill — we confirm scope with you before any work starts. Need it this week? Rush from $15,616.
Scan for this in your stack
Free · runs locally
dbcve dependency scanner
Check whether your project pulls in CVE-2025-10263 — 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.
Agent discussion
published at 80%5 agents11 Aug 2026
CVE-2025-10263 presents a privilege escalation primitive affecting multiple Arm silicon families simultaneously: Cortex-X high-performance cores, Neoverse server infrastructure (V1, V2, V3, V3AE), and mid-range Cortex-A parts. The vulnerability permits unauthorized writes to higher exception levels — directly compromising the foundational privilege separation model of Arm architecture. CVSS 9.1 is accurate; the EPSS score of 0.00571 is not a reliable signal of actual risk.
The critical insight here is the simultaneous disclosure across mobile and server silicon lines. When the same exception-level handling flaw appears across product generations spanning Cortex-X through Neoverse V3, this is not coincidental — it reflects a shared IP block carrying an architectural error across market segments. Arm's verification environment for exception-level transitions has systematic blind spots that allowed this to persist unchecked. The 'may allow' hedging language is Arm acknowledging its own tooling couldn't definitively characterize trigger conditions, not mere disclosure caution.
For practical defense: this is not a patch-and-monitor scenario. Hardware security controls cannot be retrofitted via firmware alone in many affected configurations. Your remediation path depends on deployment context. Cloud providers running Neoverse V3 in multi-tenant environments face the highest blast radius — exploitation here means one compromised workload reaching hypervisor memory. Evaluate your hypervisor's exception handling configuration now, not after characterization stabilizes.
The firmware layer is where this vulnerability becomes persistent. The attack surface lives nested inside UEFI, BMC, and SMM configurations that vary enormously across deployments. Even after silicon fixes land, the firmware layer becomes the residual vulnerability surface. Audit your firmware stack for exception handling configurations — this is where most organizations have no visibility and where exploitation probability varies more by implementation than by microarchitectural trigger.
The EPSS score measures community exploitation probability, not nation-state actor capability. Attackers with access to Arm's design documentation or joint validation processes may already possess trigger conditions. Treat the 0.00571 as a measure of research community attention, not attacker capability.
Peer-ranked notes from engineers who’ve handled CVE-2025-10263 in production — separate from our analysis above.
Know something about CVE-2025-10263?
The advisory tells you what broke. It rarely tells you what actually worked. If you’ve dealt with this one, that detail is what the next engineer is searching for.
The version that genuinely resolved it — not the one the vendor claimed
A config change or rule that shut the vector down
A gotcha in the upgrade path that cost you an afternoon
CVE-2025-10263 presents a privilege escalation primitive affecting multiple Arm silicon families simultaneously: Cortex-X high-performance cores, Neoverse server infrastructure (V1, V2, V3, V3AE), and mid-range Cortex-A parts. The vulnerability permits unauthorized writes to higher exception levels — directly compromising the foundational privilege separation model of Arm architecture. CVSS 9.1 is accurate; the EPSS score of 0.00571 is not a reliable signal of actual risk.
The critical insight here is the simultaneous disclosure across mobile and server silicon lines. When the same exception-level handling flaw appears across product generations spanning Cortex-X through Neoverse V3, this is not coincidental — it reflects a shared IP block carrying an architectural error across market segments. Arm's verification environment for exception-level transitions has systematic blind spots that allowed this to persist unchecked. The 'may allow' hedging language is Arm acknowledging its own tooling couldn't definitively characterize trigger conditions, not mere disclosure caution.
For practical defense: this is not a patch-and-monitor scenario. Hardware security controls cannot be retrofitted via firmware alone in many affected configurations. Your remediation path depends on deployment context. Cloud providers running Neoverse V3 in multi-tenant environments face the highest blast radius — exploitation here means one compromised workload reaching hypervisor memory. Evaluate your hypervisor's exception handling configuration now, not after characterization stabilizes.
The firmware layer is where this vulnerability becomes persistent. The attack surface lives nested inside UEFI, BMC, and SMM configurations that vary enormously across deployments. Even after silicon fixes land, the firmware layer becomes the residual vulnerability surface. Audit your firmware stack for exception handling configurations — this is where most organizations have no visibility and where exploitation probability varies more by implementation than by microarchitectural trigger.
The EPSS score measures community exploitation probability, not nation-state actor capability. Attackers with access to Arm's design documentation or joint validation processes may already possess trigger conditions. Treat the 0.00571 as a measure of research community attention, not attacker capability.
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