CVE-2026-85046: Google Chromium V8 Type Confusion Vulnerability
Google · Chromium V8 · NVD published 2026-09-04 · posted 2026-09-04 · last modified 2026-09-21
What it is
Type confusion in V8 in Google Chrome prior to 152.0.7977.82 allowed a remote attacker to execute arbitrary code inside the sandbox via a crafted HTML page. (Chromium security severity: High)
| Weakness | CWE-843 |
|---|---|
| CVSS vector | CVSS:3.1/AV:N/AC:L/PR:N/UI:R/S:U/C:H/I:H/A:H (source: 134c704f-9b21-4f2e-91b3-4a467353bcc0) |
| CISA due date | 2026-09-18 (for US federal agencies under BOD; a good deadline for everyone) |
| ATT&CK tactics | Initial Access → Execution |
Exploitation evidence
First exploit evidence seen: 2026-09-04 (earliest date across the sources below).
Exploited in the wild
- CISA KEV: listed since 2026-09-04. Source
Public exploit code
GitHub proof-of-concept repositories
7 public repositories from 7 accounts, first seen 2026-09-04. Most starred: atiilla/CVE-2026-85046 (8 stars), view repository.
Verify before running: public PoCs can be malicious. Read the code and only run it in an isolated lab. A PoC means exploit code is public, not that this CVE is exploited in the wild.
Sources: CISA KEV · nomi-sec/PoC-in-GitHub.
Defend the Chain
The attack chain for CVE-2026-85046 laid across the MITRE ATT&CK Enterprise tactics. Solid cards come from the MITRE CTID KEV mappings; dashed cards are inferred by CVERadar from the CWE or description. Correct defences are real ATT&CK mitigations for that technique.
Pick a red technique card on the board, then choose the defence that stops it.
Defend against T1190 Exploit Public-Facing Application Inferred
Inferred from description keywords
How to fix it
CISA required action
Apply mitigations in accordance with vendor instructions, ensuring compliance with CISA’s BOD 26-04 Prioritizing Security Updates Based on Risk (see URL in Notes) guidance and CISA’s “Forensics Triage Requirements” (see URL in Notes). Follow applicable BOD 26-04 guidance for cloud services or discontinue use of the product if mitigations are unavailable. Stakeholders are responsible for evaluating each asset's internet exposure and ensuring adherence to BOD 26-04 patching guidelines. (source: CISA KEV)
Fixed versions
- google chrome: upgrade to 152.0.7977.82 or later
- google v8: upgrade to 15.3.48 or later
Derived from the NVD CPE configuration (versionEndExcluding / versionEndIncluding). Always confirm with the vendor advisory.
Vendor advisories and patches
- https://chromereleases.googleblog.com/2026/09/stable-channel-update-for-desktop_01882797386.html (CISA KEV notes)
- https://github.com/v8/v8/commit/e0562d87ad9c17042b581582c99237d798572e67 (Patch)
MITRE ATT&CK mitigations for this chain
- M1048 Application Isolation and Sandboxing (for T1190, T1203) : Application isolation will limit what other processes and system features the exploited target can access.
- M1037 Filter Network Traffic (for T1190) : Restrict outbound network traffic from public-facing servers to prevent unauthorized connections from initiating communications with attacker-controlled infrastructure. While this may not prevent the initial exploitation, it limits the attacker's ability to verify and control the compromised server post-exploit, reduci
- M1030 Network Segmentation (for T1190) : Segment externally facing servers and services from the rest of the network with a DMZ or on separate hosting infrastructure.
- M1016 Vulnerability Scanning (for T1190) : Regularly scan externally facing systems for vulnerabilities and establish procedures to rapidly patch systems when critical vulnerabilities are discovered through scanning and through public disclosure.
- M1026 Privileged Account Management (for T1190) : Use least privilege for service accounts will limit what permissions the exploited process gets on the rest of the system.
- M1050 Exploit Protection (for T1190, T1203) : Web Application Firewalls may be used to limit exposure of applications to prevent exploit traffic from reaching the application.
- M1035 Limit Access to Resource Over Network (for T1190) : Ensure that all publicly exposed services are actually intended to be so, and restrict access to any that should only be available internally.
- M1051 Update Software (for T1190, T1203) : Update software regularly by employing patch management for externally exposed applications.
Detection Generic guidance
- Initial Access: Alert on unusual requests to the affected service (odd paths, oversized payloads, exploit strings) in WAF, reverse-proxy and application logs.
- Execution: Watch for the service process spawning shells or script interpreters (cmd.exe, powershell, sh, bash, python) via EDR process-tree rules.
Response checklist Generic guidance
- Inventory: find every instance of the affected product and version (include internet-facing and forgotten ones).
- Patch or mitigate per the vendor advisory; if you cannot patch, remove internet exposure or apply the vendor workaround.
- Assume compromise if the system was exposed before patching: hunt for the indicators in the advisory and review logs back to the disclosure date.
- Rotate credentials and secrets stored on or used by the affected system if compromise cannot be ruled out.
Sources
- NVD: CVE-2026-85046
- CVE.org record
- CISA Known Exploited Vulnerabilities catalog
- FIRST EPSS (2026-10-24)
- https://issues.chromium.org/issues/542403045 (Permissions Required)
- https://github.com/Serotav/Writeups/blob/77556c57999805fa7815a114da51d91cf24fbea9/v8/When_Sorting_Leads_To_Confusion.md (Exploit, Third Party Advisory)
- https://news.ycombinator.com/item?id=49570669 (Issue Tracking, Third Party Advisory)
- https://serotav.github.io/Writeups/v8/when-sorting-leads-to-confusion/ (Exploit, Third Party Advisory)
- https://www.cisa.gov/known-exploited-vulnerabilities-catalog?field_cve=CVE-2026-85046 (US Government Resource)