High

Intel Processor Stream Cache Privilege Escalation

IdentifiersCVE-2025-20109CWE-653· Improper Isolation or…

CVE-2025-20109 is a processor microarchitectural vulnerability in the stream cache mechanism of some Intel(R) processors. The issue is described as improper isolation or compartmentalization within the stream cache, allowing insufficient separation between security domains. Based on the provided content, a lower-privileged local process may be able to influence or observe stream-cache-related state associated with higher-privileged operations, breaking intended privilege boundaries at the CPU level. The vulnerability requires local authenticated access and is characterized as a local privilege-escalation issue rather than a remote attack surface. Dell indicates the issue is addressed on multiple affected server platforms through BIOS updates that presumably incorporate the relevant Intel firmware or microcode remediation.

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ANALYST BRIEF

Impact, mitigation & remediation

What it means. What to do now. Patch path, mitigations, and the assume-compromise checklist.

Impact

What an attacker gets, and what they’ve been doing with it.

Successful exploitation may allow an authenticated local attacker to escalate privileges on a system using a vulnerable Intel processor. The provided content indicates the flaw can undermine compartmentalization between lower- and higher-privileged execution contexts at the microarchitectural level, potentially enabling unauthorized access to privileged execution effects or security-domain crossover sufficient for elevation of privilege. The content does not provide evidence of remote code execution or direct unauthenticated exploitation.

Mitigation

If you can’t patch tonight, do this now.

If immediate remediation is not possible, reduce exposure by limiting local interactive and shell access to trusted users only, minimizing multi-tenant or untrusted workload co-residency on affected systems, and prioritizing patching on shared compute and high-value privileged systems. Because the issue is local and authenticated, hardening measures that restrict code execution by low-privileged users can reduce exploitability. However, the provided content does not describe a complete workaround short of applying BIOS or microcode updates.

Remediation

Patch, then assume compromise.

Apply vendor-provided firmware updates that address CVE-2025-20109. The provided content specifically states that Dell remediates the issue through BIOS updates on affected platforms. Examples from the content include: PowerEdge R660, R760, C6620, MX760c, R860, R960, HS5610, HS5620, R660xs, R760xs, R760xd2, T560, R760xa, XE9680, XR5610, XR8610t, XR8620t, XR7620, XE8640, XE9640, and Dell XC Core XC660/XC760 families should be updated to BIOS 2.6.5 or later; XE9680L to 2.7.5 or later; and T160, T360, R260, and R360 to 2.1.1 or later. More generally, deploy the relevant Intel-advised microcode/firmware updates via OEM BIOS packages for the affected hardware.

PUBLIC EXPLOITS

Exploits

No public exploits tracked yet. Mallory keeps watching.

VALID 0 / 0 TOTALView more in app

No public exploit code observed for this vulnerability.

EXPOSURE SURFACE

Affected products & vendors

Products and vendors Mallory has correlated with this vulnerability. Open in Mallory to drill down to specific CPE configurations and version ranges.

VendorProductType

IntelCpuhardware

Vendor-confirmed product mapping. Mallory continuously reconciles this list against your asset inventory.

ACTIVITY FEED

Recent activity

3 sources tracked across advisories, community write-ups, and news. New activity surfaces here as Mallory finds it.

3 SOURCESView more in app

zeropath blogNews

Aug 12, 2025

Intel Processor Stream Cache Isolation: Brief Summary of CVE-2025-20109 - ZeroPath Blog | ZeroPath

A high-severity privilege escalation vulnerability in the stream cache mechanism of certain Intel processors caused by improper isolation or compartmentalization at the microarchitectural level.

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Exposure mapping

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Threat actor evidence

Every observed campaign linking this CVE to a named adversary.

Associated malware

Malware families riding this exploit, with evidence and IOCs.

Detection signatures

YARA, Sigma, Snort, and vendor rules, auto-deployed to your SIEM.

Vendor-by-vendor mapping

Cross-references every affected SKU, including bundled OEM variants.

Social activity