Microsoft Edge in Microsoft Windows 10 1511, 1607, 1703, and Windows Server 2016 allows an attacker to escape from the AppContainer sandbox…

published 2017-08-08 9y ago modified 2026-06-17 4mo ago also EUVD-2017-17453

cvss: 8.8; version 3.0, NVD
cisa kev: Not listed; not in CISA's catalog
epss: 1.2%; EPSS 1.2% chance of exploitation in 30 days, percentile 67%
public exploits: 0; none known

Microsoft Edge in Microsoft Windows 10 1511, 1607, 1703, and Windows Server 2016 allows an attacker to escape from the AppContainer sandbox, aka "Microsoft Edge Elevation of Privilege Vulnerability". This CVE ID is unique from CVE-2017-8642.

Patch / fix

links 1

portal.msrc.microsoft.com/en-US/security-guidance/advisory/CVE-2017-8503 advisory

Is CVE-2017-8503 in your stack? Fencer shows which of your repositories are affected as soon as an advisory lands, and opens the fix as a pull request.

Check with Fencer

Exploit prediction

1.17% chance of exploitation in the next 30 days, higher than 67% of all scored CVEs (FIRST EPSS, 2026-11-09).

CVSS scores

assigned by	version	score	vector
NVD	3.0	8.8	CVSS:3.0/AV:L/AC:L/PR:L/UI:N/S:C/C:H/I:H/A:H
NVD	2.0	4.6	AV:L/AC:L/Au:N/C:P/I:P/A:P

Affected products

Microsoft Corporation Microsoft Edge

References

portal.msrc.microsoft.com /en-US/security-guidance/advisory/CVE-2017-8503
patch, vendor-advisory
securityfocus.com /bid/99395
vdb-entry, third-party-advisory
securitytracker.com /id/1039101
vdb-entry, third-party-advisory

Sources

CVE List CVE-2017-8503
NVD CVE-2017-8503

Fencer Intel keeps one entry per vulnerability: the CVE id wins, then GHSA, and records that alias each other are merged, except that two CVEs always keep separate entries. The same data is available as JSON.