CVE-2026-20805: Microsoft Windows Information Disclosure Vulnerability
Microsoft · Windows · NVD published 2026-01-14 · posted 2026-01-13 · last modified 2026-07-31
What it is
Exposure of sensitive information to an unauthorized actor in Desktop Windows Manager allows an authorized attacker to disclose information locally.
| Weakness | CWE-200 |
|---|---|
| CVSS vector | CVSS:3.1/AV:L/AC:L/PR:L/UI:N/S:U/C:H/I:N/A:N (source: [email protected]) |
| CISA due date | 2026-02-03 (for US federal agencies under BOD; a good deadline for everyone) |
| ATT&CK tactics | Collection |
Exploitation evidence
First exploit evidence seen: 2026-01-13 (earliest date across the sources below).
Exploited in the wild
- CISA KEV: listed since 2026-01-13. Source
Public exploit code
GitHub proof-of-concept repositories
6 public repositories from 5 accounts, first seen 2026-01-14. Most starred: ZeroDayEvil/CVE-2026-20805-PoC (92 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-2026-20805 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 T1005 Data from Local System Inferred
Inferred from CWE CWE-200
How to fix it
CISA required action
Apply mitigations per vendor instructions, follow applicable BOD 22-01 guidance for cloud services, or discontinue use of the product if mitigations are unavailable. (source: CISA KEV)
Fixed versions
- microsoft windows 10 1607: upgrade to 10.0.14393.8783 or later
- microsoft windows 10 1809: upgrade to 10.0.17763.8276 or later
- microsoft windows 10 21h2: upgrade to 10.0.19044.6809 or later
- microsoft windows 10 22h2: upgrade to 10.0.19045.6809 or later
- microsoft windows 11 23h2: upgrade to 10.0.22631.6491 or later
- microsoft windows 11 24h2: upgrade to 10.0.26100.7623 or later
- microsoft windows 11 25h2: upgrade to 10.0.26200.7623 or later
- microsoft windows server 2016: upgrade to 10.0.14393.8783 or later
- microsoft windows server 2019: upgrade to 10.0.17763.8276 or later
- microsoft windows server 2022: upgrade to 10.0.20348.4648 or later
- microsoft windows server 2022 23h2: upgrade to 10.0.25398.2092 or later
- microsoft windows server 2025: upgrade to 10.0.26100.7623 or later
Derived from the NVD CPE configuration (versionEndExcluding / versionEndIncluding). Always confirm with the vendor advisory.
Vendor advisories and patches
- https://msrc.microsoft.com/update-guide/en-US/vulnerability/CVE-2026-20805 (CISA KEV notes)
- https://msrc.microsoft.com/update-guide/vulnerability/CVE-2026-20805 (Vendor Advisory)
MITRE ATT&CK mitigations for this chain
- M1057 Data Loss Prevention (for T1005) : Data loss prevention can restrict access to sensitive data and detect sensitive data that is unencrypted.
Detection Generic guidance
- Collection: Watch for bulk reads of databases, file shares or mailboxes by the affected service.
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.