CVE-2026-62898 — Microsoft QUIC Information Disclosure Vulnerability

Executive Summary

Use after free in Microsoft QUIC allows an unauthorized attacker to disclose information over a network.

Overview

7.5

CVSS HIGH

Important

MS Severity

Not Exploited

MS Exploit Status

Less Likely

MS Exploit Likelihood

Category Information Disclosure

Released Aug 11 2026

Last Updated Aug 11 2026

Publicly Disclosed No

CISA KEV Not Listed

Known Exploits None Known

EPSS Score 0.01136 — 0.63721 percentile

NVD CVSS 7.5 HIGH — matches MSRC

CVSS Vector

CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:N/A:N/E:U/RL:O/RC:C

ATTACK VECTOR

Network

ATTACK COMPLEXITY

Low

PRIVILEGES REQUIRED

None

USER INTERACTION

None

SCOPE

Unchanged

CONFIDENTIALITY

High

INTEGRITY

None

AVAILABILITY

None

EXPLOIT CODE MATURITY

Unproven

REMEDIATION LEVEL

Official Fix

REPORT CONFIDENCE

Confirmed

Temporal Score: 6.5

EPSS Score

0.01136

probability of exploitation in the next 30 days

0.63721 percentile - updated 2026-08-14

View on FIRST.org

Affected Products

11 affected products

Product	KB Article	Severity	Impact	Restart Required
.NET 10.0 installed on Linux	`5122106 (Security Update)`	Important	Information Disclosure	Maybe
.NET 10.0 installed on Mac OS	`5122106 (Security Update)`	Important	Information Disclosure	Maybe
.NET 10.0 installed on Windows	`5122106 (Security Update)`	Important	Information Disclosure	Maybe
.NET 8.0 installed on Linux	`5122104 (Security Update)`	Important	Information Disclosure	Maybe
.NET 8.0 installed on Mac OS	`5122104 (Security Update)`	Important	Information Disclosure	Maybe
.NET 8.0 installed on Windows	`5122104 (Security Update)`	Important	Information Disclosure	Maybe
.NET 9.0 installed on Linux	`5122105 (Security Update)`	Important	Information Disclosure	Maybe
.NET 9.0 installed on Mac OS	`5122105 (Security Update)`	Important	Information Disclosure	Maybe
.NET 9.0 installed on Windows	`5122105 (Security Update)`	Important	Information Disclosure	Maybe
Microsoft Visual Studio 2022 version 17.14	`(Security Update)`	Important	Information Disclosure	Unknown
Microsoft Visual Studio 2026 version 18.8	`(Security Update)`	Important	Information Disclosure	Unknown

Patches

4 patches

Article	Type	Restart
`5122106`	Security Update	Maybe
`5122104`	Security Update	Maybe
`5122105`	Security Update	Maybe
	Security Update	Unknown

Known Exploits

No known exploits have been linked for this CVE yet. When available, exploit references will be sourced from public repositories and may be unverified, incomplete, or non-functional. Always review code carefully before use in any environment.

Acknowledgments

Quac Tran

References

MSRC Advisory MITRE NVD