CVE-2026-106281

Executive Summary

CVE-2026-106281 is a use-after-free (UAF) vulnerability in the Tint component of Google Chrome versions prior to 155.0.8059.39, rated High severity by the Chromium team with a CVSS 3.1 base score of 9.6. A remote attacker can trigger the flaw via a crafted HTML page, potentially leading to arbitrary code execution outside the browser sandbox. All unpatched Chrome deployments on desktop, and any embedder of the Chromium engine that ships the affected Tint code path, are in scope.

Technical Analysis

The vulnerability is a use-after-free (CWE-416) in "Tint." Tint is Chromium's shading language and compiler toolchain used for GPU/rendering shader translation; the NVD description explicitly names "Tint" and "Tint in Google Chrome" as the vulnerable component. A UAF occurs when the process references memory after it has been freed. In Tint's context this typically involves compiler-internal object lifetime management: an object (node, IR value, or intermediate representation) is released while a still-live reference or code path continues to dereference it. When attacker-influenced input reaches this code path, the freed memory region can be reallocated and its contents controlled, turning the dangling reference into a primitive that is written to or read from under attacker control.

The attack surface is the rendering pipeline exposed to web content. Because the NVD entry states the flaw is reachable "via a crafted HTML page," the trigger is client-side and requires user interaction (the victim loading the page or content that embeds it). The CVSS vector (AV:N/AC:L/PR:N/UI:R/S:C/C:H/I:H/A:H) corroborates: network-reachable, low attack complexity, no privileges, user interaction required, Scope Changed — the impact crosses a security boundary. Combined with the NVD statement that the attacker can "potentially execute arbitrary code outside the sandbox," the exploitation impact is a sandbox escape: code executed in the context of the browser/renderer process can affect resources beyond the sandboxed renderer.

The exact internal classes, functions, or object names involved in the Tint UAF are not disclosed in the provided data. No public PoC, exploit code, or Nuclei template is known, and no affected-version package list or OSV package data is available. Patch confidence is 0/4: no patch evidence exists in any tracked source, so the flaw must be treated as unpatched even though version 155.0.8059.39 is identified as the fixed release.

Exploitation Scenarios

Per the strict constraints, no internal function or API names beyond "Tint" and "crafted HTML page" are available; the chain below is described at the vulnerability-class and component level.

1. Reconnaissance / target identification. The attacker identifies targets running Chrome < 155.0.8059.39. This is a broad, opportunistic target set since Chrome auto-updates lag and many enterprise fleets pin older builds. No authentication or special network position is required; the victim simply must browse to or load attacker-controlled content.

2. Trigger of the UAF. The attacker delivers a crafted HTML page (the delivery vector named in the NVD description). The page causes the browser to feed crafted shader/graphics input into the Tint compilation path. At the vulnerable point, an object is freed while a live reference still points to it — the classic UAF condition. The "crafted" nature of the page implies the input is shaped to control the timing and allocation pattern around the free.

3. Execution at the vulnerability-class level. After the free, the attacker arranges for the freed memory to be reallocated with attacker-controlled contents, so the dangling reference resolves to data the attacker controls. Through this controlled reference, the attacker can corrupt adjacent memory and redirect execution or data flow within the affected process. Because the NVD description states arbitrary code execution "outside the sandbox" is possible, the exploitation objective is code execution in a less-restricted context than a normal renderer — i.e., the UAF is a step toward breaking the Chrome sandbox boundary (consistent with the changed scope in the CVSS vector).

4. Post-exploitation impact. Successful exploitation yields arbitrary code execution outside the sandbox, meaning the attacker could access resources not ordinarily reachable from sandboxed web content, persist within the user's session, and pivot to further host-level actions. Confidentiality, integrity, and availability impacts are all assessed as High per the CVSS subscores.

No public PoC is available; the attack chain is inferred from the vulnerability class (CWE-416) and the NVD description. Whether the UAF is reachable from a standard web renderer without additional chained bugs is not documented in the provided data.

Impact Assessment

Impact is High across confidentiality (C:H), integrity (I:H), and availability (A:H), with changed scope (S:C) and a base score of 9.6. In business terms:

• Affected systems: Google Chrome < 155.0.8059.39 on all supported desktop platforms, and potentially any downstream Chromium embedder that compiles and exposes the affected Tint path. The provided data lists no specific OSV packages, so embedder scope cannot be precisely enumerated.
• Blast radius: Sandbox escape means a single malicious page visit can, in the worst case, lead to code execution beyond the web-content sandbox — increasing the risk of host compromise, credential theft, and lateral movement, not merely isolated tab compromise.
• Exploitation prerequisites: User interaction (UI:R) is required — the victim must load the crafted HTML. Attack complexity is Low (AC:L) and no privileges (PR:N) or prior access are needed, so the barrier to a working exploit is low once a reliable trigger exists.
• Weaponization risk: High-value target for exploit kit and APT use given the High severity and sandbox-escape impact. However, no exploit code, no KEV listing, and no confirmed in-the-wild exploitation are indicated in the data as of this report.

Detection Guidance

Sigma Rule

title: Potential Chrome Tint Use-After-Free Exploitation (CVE-2026-106281)
id: 0d6c9f2a-8b4e-4f1c-9a7d-2f2e6c1b5a10
status: experimental
description: Detects suspicious child process or crash behavior consistent with Chrome renderer exploitation attempts targeting CVE-2026-106281 (Tint UAF, prior to 155.0.8059.39)
logsource:
  category: process_creation
  product: windows
detection:
  selection_chrome:
    ParentImage|endswith:
      - '\chrome.exe'
      - '\msedge.exe'
      - '\chromium.exe'
  selection_susp:
    Image|endswith:
      - '\cmd.exe'
      - '\powershell.exe'
      - '\wscript.exe'
      - '\cscript.exe'
      - '\rundll32.exe'
      - '\regsvr32.exe'
  condition: selection_chrome and selection_susp
falsepositives:
  - Legitimate browser extensions or enterprise management launching scripts from a browser context
level: high
tags:
  - attack.t1189
  - cve.2026-106281

YARA Rule

rule CVE_2026_106281_Chrome_Tint_UAF_Hunt
{
    meta:
        description = "Heuristic hunt for files/artifacts referencing Chrome Tint UAF context CVE-2026-106281"
        author = "Threat Intelligence"
        reference = "CVE-2026-106281"
        date = "2026-01-01"
        severity = "high"
    strings:
        $tint1 = "Tint" ascii wide nocase
        $chrome1 = "Google Chrome" ascii wide nocase
        $chrome2 = "Chrome/15" ascii wide
        $uaf1 = "use-after-free" ascii wide nocase
        $cve = "CVE-2026-106281" ascii wide
    condition:
        uint16(0) == 0x5A4D and
        (2 of ($tint*, $chrome*) and 1 of ($uaf1, $cve)) and
        filesize < 50MB
}

Suricata IDS Rule

alert http any any -> any any (msg:"CVE-2026-106281 Possible Chrome Tint UAF Drive-By Exploit Delivery"; flow:established,to_client; http.method; content:"GET"; http.response_body; content:"<html"; nocase; classtype:attempted-user; reference:cve,2026-106281; reference:url,www.cve.org/CVERecord?id=CVE-2026-106281; sid:2026106281; rev:1;)

Elastic Detection

process where event.category == "process" and
  process.parent.name in ("chrome.exe", "msedge.exe", "chromium.exe") and
  process.name in ("cmd.exe", "powershell.exe", "wscript.exe", "cscript.exe", "rundll32.exe")

Splunk SPL Query

index=endpoint OR index=edr (process_name IN ("chrome.exe","msedge.exe","chromium.exe") OR parent_process_name IN ("chrome.exe","msedge.exe","chromium.exe")) AND (process_name IN ("cmd.exe","powershell.exe","wscript.exe","cscript.exe","rundll32.exe","regsvr32.exe")) | stats count by host, user, parent_process_name, process_name, _time | where count > 0

Wazuh OSSEC Rule

<group name="windows,chrome,cve-2026-106281,">
  <rule id="2026106" level="12">
    <if_sid>61603</if_sid>
    <field name="win.eventdata.parentImage">chrome\.exe$|msedge\.exe$|chromium\.exe$</field>
    <field name="win.eventdata.image">cmd\.exe$|powershell\.exe$|wscript\.exe$|cscript\.exe$|rundll32\.exe$</field>
    <description>CVE-2026-106281: Suspicious child process spawned from browser context (possible Chrome Tint UAF exploitation)</description>
    <mitre>
      <id>T1189</id>
    </mitre>
    <group>cve_2026_106281,</group>
  </rule>
</group>

Mitigation & Patch Guidance

Patch confidence: 0/4 (UNPATCHED — no patch evidence from any tracked source).

1. Immediate mitigations:

   • Verify whether your Chrome fleet is at or above 155.0.8059.39; treat anything below as vulnerable.
   • Enforce auto-update and push the update through enterprise management (Chrome Browser Cloud Management / GPO / Intune) as soon as it is available.
   • Where immediate upgrade is impossible, reduce exposure: restrict browsing to allow-listed sites, block unknown/uncategorized web content at the proxy, and consider disabling or tightly controlling GPU/shader-heavy web content until patched.
   • Enable Chrome's site isolation and renderer sandbox features (do not disable the sandbox) so that any successful UAF is contained to the strongest extent possible.

2. Patch / upgrade steps:

   • Upgrade Google Chrome to 155.0.8059.39 or later on all endpoints.
   • For Chromium embedders, rebuild against a Chromium revision that includes the fix; consult your embedder's advisory since no OSV package data is available here.
   • Re-scan managed endpoints after rollout to confirm version compliance.

3. Long-term hardening:

   • Maintain a tracked, enforced browser update baseline and monitor CVE feeds for Chromium/Chrome Tint advisories.
   • Deploy memory-safety detections (e.g., renderer crash telemetry, exploit-mitigation logging) and monitor for unusual renderer-to-child process spawning.
   • Reduce reliance on remote web browsing for high-value workflows; apply least privilege and application control to limit post-exploitation impact.

References

• NVD — CVE-2026-106281: https://nvd.nist.gov/vuln/detail/CVE-2026-106281
• Chrome Releases (Stable Channel Update): https://chromereleases.googleblog.com/
• CWE-416 Use After Free: https://cwe.mitre.org/data/definitions/416.html
• CISA Known Exploited Vulnerabilities Catalog (not listed as of this report): https://www.cisa.gov/known-exploited-vulnerabilities-catalog
• FIRST EPSS (not yet scored): https://www.first.org/epss/

No threat actor campaign attribution or confirmed exploit-in-the-wild evidence is present in the provided data; exploitation status is currently theoretical based on the vulnerability class.