Microsoft Edge: Remote code execution via double free
Summary
A double free vulnerability (CWE-415) in Microsoft Edge (Chromium-based) allows an unauthorized attacker to execute code over the network. An attacker needs a user to visit a malicious page or open malicious content, because user interaction is required. The CVSS score is 8.8 (High), and CISA SSVC rates the technical impact as total.
Affected
- Microsoft Edge (Chromium-based), versions from 1.0.0.0 before 154.0.4258.37 according to the official CVE record.
- Some third-party sites list the upper limit as 154.0.4258.48. This discrepancy is unresolved; check the MSRC product table.
Fixed in
- Fixed build: 154.0.4258.48 according to third-party sites (OffSeq, Strix). Not confirmed on the MSRC page; verify before rollout.
- A separate Tenable reference mentions Microsoft Edge (Chromium) 155.0.4283.62 as a possible newer target. This is unconfirmed and not a verified fix.
Workaround
- Unknown. No workaround is documented in the sources reviewed; the documented remedy is to update.
Exploitation
- No known active exploitation. The CVE is not listed in CISA's Known Exploited Vulnerabilities catalog.
- No public proof of concept has been confirmed. Microsoft's exploit code maturity is E:U (unproven).
- The 0.77% EPSS value could not be verified.
Our recommendation
- Update Microsoft Edge to the fixed build as listed on the MSRC advisory (currently 154.0.4258.48 or later) on all Windows endpoints.
- Keep Edge auto-update enabled and check the installed version with Intune, WSUS or a software inventory.
- Until patched, instruct users to avoid untrusted links and websites.
- Prioritize the update because Edge is the default browser on most Windows workstations, but it is less urgent than an internet-facing server flaw.
Information from Microsoft (Patch Tuesday October 2026)
Public exploits
PoC-in-GitHub, Metasploit and Exploit-DB list nothing for this CVE.
Research sources
- MSRC advisory CVE-2026-83831 msrc.microsoft.com
- CVE record mirror (threatint) cve.threatint.com
- OffSeq (patch version) radar.offseq.com
- Strix (affected range) www.strix.ai
- TheHackerWire (exploit and KEV status) www.thehackerwire.com
- AhnLab ASEC (October 2026 updates) asec.ahnlab.com
- VulDB (conflicting classification) vuldb.com
- Vulners/PT (Tenable plugin reference) vulners.com
Researched and written up in English and German by an AI (Claude by Anthropic) based on NVD, CISA, EPSS and the sources listed. The vendor information is authoritative. Researched on 31 Oct 2026, 10:07.
Original description (NVD)
Double free in Microsoft Edge (Chromium-based) allows an unauthorized attacker to execute code over a network.
NVD references (1)
Sources
The tracker combines official, freely usable data sources – updated continuously:
- NVD (NIST) – CVEs, rating (CVSS), affected products
- CISA KEV – vulnerabilities confirmed by CISA as actively exploited
- CISA Vulnrichment – CISA assessment (SSVC) in the official CVE record
- FIRST EPSS – probability of exploitation
- Microsoft MSRC – Patch Tuesday: vulnerabilities, severity, updates
- PoC-in-GitHub – public proof-of-concept repositories
- Metasploit (Rapid7) – modules of the Metasploit Framework
- Exploit-DB (OffSec) – archive of public exploits (links only)
- Patch days: official vendor pages (linked per vendor) (Vendor patch days)
This product uses data from the NVD API but is not endorsed or certified by the NVD. EPSS data © FIRST.org.
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