CVE-2026-32788

Executive Summary

CVE-2026-32788 is an uncontrolled search path vulnerability (CWE-427) in Intel's Approximate Bayesian Inference Framework, affecting all builds before commit #484c949. The flaw resides in the Ring 3 user-application layer and allows a local adversary who already holds privileged user rights to escalate privileges through path interception when the vulnerable component is invoked. Successful exploitation yields high confidentiality, integrity, and availability impact on the affected host, though the CVSS base score of 6.7 reflects the high privileges and attack requirements needed to reach the flaw.

Technical Analysis

The vulnerability class here is CWE-427: Uncontrolled Search Path Element. This class occurs when an application loads an executable, library, configuration file, or other resource by name without specifying an absolute path or otherwise validating the location from which the resource is resolved. The operating system then searches a defined set of directories — for example, the current working directory, entries in a PATH-style environment variable, or a relative resource directory — in order. If any of those search locations is writable by an adversary, the adversary can plant a malicious file bearing the expected name and cause it to be loaded instead of the legitimate one.

Per the NVD description, the affected component is the Approximate Bayesian Inference Framework, and the flaw exists "within Ring 3: User Applications." This places the vulnerability in a user-mode context rather than in the kernel or a privileged service. The description states that the attack is local (AV:L), that it requires a privileged user (PR:H), that attack requirements are present (AT:P), and that no user interaction is required (UI:N). The consequence is escalation of privilege.

No function names, library names, environment variable names, file paths, or endpoints are disclosed in the supplied NVD description or CNA title. Accordingly, the precise search-path mechanism (for example, which environment variable, which directory ordering, or which resource type is resolved) cannot be confirmed from the available data. What can be stated with confidence from the data is: a resource is resolved through an uncontrolled search path by a user-mode component of the framework, and an adversary with write access to a directory appearing earlier in that search order can substitute an attacker-controlled file. Because the vector is local and independent of network services, the attack surface is the host filesystem and the process-loading behavior of the framework when a privileged user launches or invokes it.

CVSS subscores align with this reading: Scope is Unchanged (S:U), so the exploit remains within the same security authority — the adversary elevates within the local host rather than crossing a trust boundary into another component. Confidentiality, Integrity, and Availability are each rated High (C:H/I:H/A:H), indicating that a successful path-interception leading to arbitrary code execution in the privileged user's context can fully compromise the local system. The PR:H requirement tempers the score, and the AT:P requirement (attack requirements present, e.g., a specific execution condition or privilege state) further limits applicability. EPSS sits at 0.00161, in the 4.6th percentile of exploited CVEs, reflecting very low near-term exploitation likelihood. The vulnerability is not listed in CISA KEV.

Exploitation Scenarios

Because no public exploit code and no Nuclei template are available, the attack chain below is inferred strictly from the vulnerability class (CWE-427) and the qualifiers in the NVD description. No specific function names, paths, or parameters are asserted, as none are provided in the source data.

1. Reconnaissance / target identification. The adversary obtains local access to a host where Intel's Approximate Bayesian Inference Framework is installed and where a privileged user is expected to invoke the framework. The adversary has unprivileged execution on the host but seeks to reach privileged context (or an adversary who is a privileged user seeks to elevate further or to compromise a higher-integrity process). Because the vector is AV:L, remote scanning is not applicable; identification is host-local.

2. Triggering the flaw class. The adversary determines the search order the user-mode framework uses to resolve the resources it loads. In a classic CWE-427 scenario, the framework resolves one or more resources lazily by bare name rather than by fully qualified path, and the resolution process consults a location the adversary can write to. The adversary places a file with the expected name at a location that precedes the legitimate resource in the search order. This step corresponds to the CVSS AT:P condition — the adversarial file only takes effect when the vulnerable resolution path is actually exercised.

3. Execution. When the privileged user invokes the framework (matching the PR:H requirement — the victim context is privileged), the framework loads the attacker-controlled resource instead of the legitimate one. At the vulnerability-class level, the payload executes with the privileges of the invoking user. The description specifies UI:N, so no additional end-user interaction beyond the privileged invocation is required.

4. Post-exploitation impact. Given C:H/I:H/A:H under unchanged scope, a successful intercept yields full read/write/execute control within the compromised user context on the local host. The description explicitly limits subsequent-system impact to none (SC:N/SI:N/SA:N), meaning the exploit is contained to the local system and does not directly propagate to other systems as a direct consequence of this vulnerability.

No public PoC is available; the chain above is a vulnerability-class reconstruction and should not be read as a verified exploit recipe.

Impact Assessment

The affected product is Intel's Approximate Bayesian Inference Framework, a user-mode (Ring 3) software component. Systems impacted are hosts where the framework is installed and where a privileged user account performs an invocation that resolves resources through the uncontrolled search path. The blast radius per host is the full integrity, confidentiality, and availability of that local system, contingent on the attacker already satisfying the PR:H and AT:P preconditions.

From a business perspective, the primary risk is a local elevation-of-privilege foothold: an attacker with limited local access can convert that access into privileged execution on an endpoint used for statistical/modeling workloads, potentially exposing data processed by the framework, tampering with computed results, or establishing persistence. Because scope is unchanged and no subsequent-system impact is reported, cross-host lateral movement is not a direct consequence of this CVE and would depend on other weaknesses. EPSS (0.00161) and the absence of KEV listing indicate limited observed exploitation; nonetheless, CWE-427 flaws are conceptually straightforward to exploit when the search order is understood, so deployment-wide exposure should be measured by how many hosts have the framework installed with a privileged invocation pattern. The high PR:H prerequisite substantially narrows the population of viable victims compared to an unauthenticated remote flaw.

Detection Guidance

Sigma Rule

title: Potential Uncontrolled Search Path Abuse - Intel Approximate Bayesian Inference Framework (CVE-2026-32788)
id: 3f9c2a10-8b7e-4d21-9c5a-cve202632788
status: experimental
description: Detects execution of processes from user-writable directories consistent with CWE-427 path interception against a user-mode component of the Approximate Bayesian Inference Framework.
references:
  - https://nvd.nist.gov/vuln/detail/CVE-2026-32788
author: Valters IT Threat Intelligence
date: 2026/01/01
logsource:
  product: windows
  category: process_creation
detection:
  selection_image:
    Image|endswith:
      - '\\AppData\\Local\\Temp\\*.exe'
      - '\\AppData\\Roaming\\*.exe'
      - '\\Users\\Public\\*.exe'
      - '\\ProgramData\\*.exe'
  selection_parent:
    ParentImage|contains:
      - 'bayesian'
      - 'inference'
  condition: selection_image and selection_parent
falsepositives:
  - Legitimate portable tooling launched from user directories
level: medium
tags:
  - attack.t1574.007
  - attack.privilege_escalation

YARA Rule

rule CVE_2026_32788_SearchPath_Interception
{
    meta:
        description = "Heuristic detection of files staged in writable directories that may be used for uncontrolled search path (CWE-427) interception against the Approximate Bayesian Inference Framework"
        reference = "https://nvd.nist.gov/vuln/detail/CVE-2026-32788"
        author = "Valters IT Threat Intelligence"
        date = "2026-01-01"
        cwe = "CWE-427"
    strings:
        $p1 = "bayesian" ascii nocase
        $p2 = "inference" ascii nocase
        $p3 = "search path" ascii nocase
    condition:
        (uint16(0) == 0x5A4D or uint32(0) == 0x464C457F) and
        any of ($p*) and
        filesize < 20MB
}

Suricata IDS Rule

alert tcp $HOME_NET any -> $HOME_NET any (msg:"CVE-2026-32788 Possible Approximate Bayesian Inference Framework CWE-427 Search Path Abuse (local staging channel)"; flow:to_server,established; content:"bayesian"; nocase; content:"inference"; nocase; classtype:attempted-user; sid:202632788; rev:1; metadata:created_at 2026_01_01, cve CVE-2026-32788, cwe CWE-427;)

Elastic Detection

process where event.type == "start" and
  process.parent.name : "*bayesian*" and
  process.executable : (
    "?:\\Users\\*\\AppData\\Local\\Temp\\*",
    "?:\\Users\\*\\AppData\\Roaming\\*",
    "?:\\ProgramData\\*",
    "?:\\Users\\Public\\*"
  )

Splunk SPL Query

index=endpoint sourcetype=WinEventLog:Security (EventCode=4688 OR EventCode=1)
| eval proc=lower(New_Process_Name)
| eval par=lower(Parent_Process_Name)
| where (match(proc,"\\appdata\\local\\temp\\|\\appdata\\roaming\\|\\programdata\\|\\users\\public\\")
    OR match(proc,"\\windows\\temp\\"))
| where match(par,"bayesian") OR match(par,"inference")
| table _time, host, user, par, proc, Process_Command_Line
| sort - _time

Wazuh OSSEC Rule

<group name="windows,cve-2026-32788,">
  <rule id="202632788" level="10">
    <if_sid>60000</if_sid>
    <field name="win.eventdata.parentImage">(?i)bayesian|inference</field>
    <field name="win.eventdata.image">(?i)\\AppData\\(Local\\Temp|Roaming)\\|\\ProgramData\\|\\Users\\Public\\</field>
    <description>CVE-2026-32788: Possible uncontrolled search path (CWE-427) abuse against Approximate Bayesian Inference Framework - child process executed from writable directory.</description>
    <mitre>
      <id>T1574.007</id>
    </mitre>
    <group>privilege_escalation,</group>
  </rule>
</group>

Mitigation & Patch Guidance

Patch confidence: 0/4 (UNPATCHED — no patch evidence from any tracked source). No vendor advisory, workaround, or fix version is currently available.

1) Immediate mitigations

• Restrict write access to directories that precede legitimate framework resources in the host's search order. In practical terms, remove unnecessary write permissions for standard users on directories such as temporary folders, the current working directory of the framework, and any user-writable library or executable paths used during invocation.
• Enforce least privilege: reduce the number of privileged accounts that invoke the framework. The PR:H requirement means a lower-privileged invocation context drastically reduces exploitability.
• Where feasible, apply OS-level hardening such as controlled folder access, DLL/loader search order hardening settings, and application allowlisting that blocks execution of unsigned binaries from user-writable directories.
• Monitor for staged files appearing in writable directories with names matching framework components.

2) Patch / upgrade steps

• The CNA description references commit #484c949 on the framework's source repository as the boundary before which versions are affected. Track that commit and upgrade to a build at or after it once a distributable artifact is published.
• Since no vendor advisory or fix version has been confirmed by tracked sources at this time, validate any candidate build against the upstream repository and confirm the search-path resolution has been corrected before deploying.
• Re-test the privileged invocation path after upgrade to confirm the uncontrolled search element no longer resolves to user-writable locations.

3) Long-term hardening

• Adopt a secure-by-default build standard that requires fully qualified paths for all resource loading in user-mode components.
• Integrate static analysis for CWE-427 patterns into CI/CD for the framework and any dependent tooling.
• Maintain an inventory of hosts with the framework installed to prioritize remediation as soon as a fix is released.
• Continue monitoring vendor channels, since no CISA KEV listing and no CISA-published due date currently apply.

References

• NVD — CVE-2026-32788: https://nvd.nist.gov/vuln/detail/CVE-2026-32788
• CWE-427 — Uncontrolled Search Path Element: https://cwe.mitre.org/data/definitions/427.html
• MITRE ATT&CK — T1574.007 Hijack Execution Flow: Path Interception by PATH Environment Variable: https://attack.mitre.org/techniques/T1574/007/
• FIRST — EPSS (CVE-2026-32788 score 0.00161): https://api.first.org/data/v1/epss?cve=CVE-2026-32788
• CISA Known Exploited Vulnerabilities Catalog (CVE-2026-32788 not listed as of this report): https://www.cisa.gov/known-exploited-vulnerabilities-catalog

No threat actor campaigns or exploit-in-the-wild evidence for CVE-2026-32788 are identified in the supplied data. Public PoC status is reported as "Public," but no exploit code or Nuclei template is available, and the report content should be treated as vulnerability-class analysis only.