Microsoft Edge (Chromium-based): Privilege escalation via integer overflow
Summary
Microsoft Edge (Chromium-based) contains an integer overflow or wraparound (CWE-190) that allows an unauthorized attacker to elevate privileges over a network. According to the CNA record, the CVSS vector requires user interaction (UI:R), so exploitation most likely requires a user to visit a malicious or compromised web page. The CVSS score is 8.8 (CNA) but VulDB rates it 6.3 (Medium), and public technical details are limited.
Affected
- Microsoft Edge (Chromium-based) from 1.0.0.0 to before 154.0.4258.62 (CNA record)
- VulDB gives the upper boundary as 154.0.4258.37; the boundary must be confirmed on the MSRC page
Fixed in
- Build 154.0.4258.62 or later (listed in MSRC security guidance; the advisory page could not be verified directly)
- Newer stable builds are available; update to the latest stable release
Workaround
- No workaround is needed when a fixed build is installed.
- Unknown: whether any configuration setting reduces exposure.
Exploitation
- Not known to be exploited in the wild.
- Not listed in the CISA KEV catalogue according to a third-party tracker (not checked directly).
- No public proof-of-concept found.
- CISA SSVC: Exploitation none, Automatable no, Technical Impact total.
Our recommendation
- Update Microsoft Edge to build 154.0.4258.62 or later on all managed Windows devices.
- Check for pinned Edge versions or blocked updates and remove them.
- Confirm the installed version on all endpoints, for example via the Edge version in edge://settings/help.
- Restrict browsing of untrusted sites where possible and monitor NVD and the MSRC advisory for updates.
Information from Microsoft (Patch Tuesday October 2026)
Public exploits
PoC-in-GitHub, Metasploit and Exploit-DB list nothing for this CVE.
Research sources
- MSRC Security Update Guide: CVE-2026-88077 msrc.microsoft.com
- MSRC Security Guidance msrc.microsoft.com
- MSRC Update Deployments msrc.microsoft.com
- Microsoft Edge stable channel release notes archive learn.microsoft.com
- VulDB entry 428530 vuldb.com
- Strix CVE record CVE-2026-88077 www.strix.ai
- CVE Threat Intelligence record CVE-2026-88077 cve.threatint.com
- OffSeq threat radar entry CVE-2026-88077 radar.offseq.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, 09:04.
Original description (NVD)
Integer overflow or wraparound in Microsoft Edge (Chromium-based) allows an unauthorized attacker to elevate privileges 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.
Affected? We can help.
We check whether your systems are affected, install updates and close the gap – continuously with the System Health Checker if you wish.