CVE-2023-32049

From Exploited flaws, HARD’s guide to the flaws being used in attacks · Checked
This article is about a flaw in Microsoft Windows. For every flaw being used in attacks, see Exploited flaws; for Microsoft’s, see Microsoft flaws being used in attacks.

CVE-2023-32049 is a security flaw in Microsoft Windows, Microsoft’s operating system for PCs and servers. Attackers can get past a security protection in Microsoft Windows. The US Cybersecurity and Infrastructure Security Agency (CISA) added it to its catalog of flaws known to be used in attacks on 11 Jul 2023.[1]

Microsoft Windows is in things households have, such as phones, computers, browsers and everyday apps, so the fix matters at home as much as at work. Fixed in version 10.0.17763.4645, 10.0.20348.1850, 10.0.22000.2176 and 10.0.19044.3208 and others.

Description

CISA calls it a defender smartScreen security feature bypass in Microsoft Windows. In its words: “Microsoft Windows Defender SmartScreen contains a security feature bypass vulnerability that allows an attacker to bypass the Open File - Security Warning prompt.”[1]

It scores 8.8 out of 10 on the Common Vulnerability Scoring System, which rates it high, scored by the organisation that published the CVE using CVSS 3.1.[2]

Affected versions

NVD’s record lists these fixed versions: in each line, everything before the version shown is affected.[2]

ProductFixed in
Windows 10 Version 180910.0.17763.4645
Windows Server 201910.0.17763.4645
Windows Server 2019 (Server Core installation)10.0.17763.4645
Windows Server 202210.0.20348.1850
Windows 11 version 21H210.0.22000.2176
Windows 10 Version 21H210.0.19044.3208
Windows 11 version 22H210.0.22621.1992
Windows 10 Version 22H210.0.19045.3208

Every device with Microsoft Windows needs the update.

Exploitation

CISA added it to its catalog of known exploited vulnerabilities on 11 Jul 2023, within a day of it being made public. CISA lists a flaw only when it has reliable evidence of it being exploited, and gave US federal agencies until 1 Aug 2023 to fix it.[1]

FIRST’s Exploit Prediction Scoring System, which estimates how likely a flaw is to be used in attacks in the next 30 days from what it sees across the internet, puts it at 4%. That’s in the top 10% of the flaws it scores.[4]

CISA assesses it as not automatable: each attack takes some work.

CISA doesn’t say who was attacked, or how.

Fix

Microsoft has published a fix or advice.[3] CISA’s required action: “Apply updates per vendor instructions or discontinue use of the product if updates are unavailable.”[1]

  1. Update Microsoft Windows now.On Windows: Settings, Windows Update, Check for updates, then restart. Office updates come the same way, or from any Office app: File, Account, Update Options. Then turn on automatic updates, so the next fix arrives on its own.
  2. Check you’re on 10.0.17763.4645 or later.Fixed in version 10.0.17763.4645, 10.0.20348.1850, 10.0.22000.2176 and 10.0.19044.3208 and others. Anything older is what attackers are going after.
  3. If there’s no update, stop using it.CISA’s advice when a flaw being used in attacks has no fix is to stop using the product until it does.

Timeline

DateEvent
The flaw is made public in the National Vulnerability Database, with a severity score of 8.8.[2]
CISA adds it to its catalog of flaws known to be used in attacks.[1]
CISA’s deadline for US government agencies to fix it.[1]
FIRST puts the odds of it being used in attacks in the next 30 days at 4%.[4]

See also

Other Microsoft Windows flaws

Similar flaws

Added the same day

  • CVE-2023-36874, Microsoft Windows: error reporting service privilege escalation ·
  • CVE-2023-35311, Microsoft Outlook: security feature bypass ·
  • CVE-2023-32046, Microsoft Windows: MSHTML platform privilege escalation ·
  • CVE-2022-31199, Netwrix Auditor: insecure object deserialization ·

Every Microsoft flaw on CISA’s list · Everything added in July 2023

References

  1. ^ Cybersecurity and Infrastructure Security Agency. “Microsoft Windows Defender SmartScreen Security Feature Bypass Vulnerability”. Known Exploited Vulnerabilities Catalog, added 11 Jul 2023.
  2. ^ National Institute of Standards and Technology. “CVE-2023-32049 Detail”. National Vulnerability Database, published 11 Jul 2023.
  3. ^ Microsoft. Advisories and fixes: msrc.microsoft.com, msrc.microsoft.com.
  4. ^ FIRST. “Exploit Prediction Scoring System”. EPSS 0.042, percentile 90.9, 31 Oct 2026.
  5. CVE Program. “CVE-2023-32049”. The official CVE record.

This article is built from CISA’s catalog (version 2026.10.30), NVD’s record and FIRST’s scores, kept in HARD’s database and checked every morning. The plain English is HARD’s.