# Microsoft May 2024: 2 actively exploited zero-days · pwn.watch

> CVE-2024-30040: Microsoft Windows MSHTML Platform contains an unspecified vulnerability that allows for a security feature bypass. CVE-2024-30051: Microsoft DWM Core Library contains a privilege escalation vulnerability that allows an attacker to gain SYSTEM privileges. Added to the CISA KEV catalog on 2024-05-14. CISA lists known use in ransomware campaigns.

Page: https://pwn.watch/i/microsoft-zero-days-may-2024-30040-30051 · generated 2026-10-22T22:00:08.805Z

## Status
- Severity: high · status: closed · patch: patched
- Product: Microsoft DWM Core Library, Windows
- Started: 2024-05-14 · closed: 2024-05-14
- CVEs: CVE-2024-30040, CVE-2024-30051
- Affected: See vendor advisory (versions are not listed in the KEV record)
- Fixed in: See vendor advisory linked in sources

## Follow this incident
- RSS (one item per update): https://pwn.watch/i/microsoft-zero-days-may-2024-30040-30051/feed.xml
- JSON Feed: https://pwn.watch/i/microsoft-zero-days-may-2024-30040-30051/feed.json
- Full data (timeline, sources, posts, agentBrief): https://pwn.watch/i/microsoft-zero-days-may-2024-30040-30051.json
- This file: https://pwn.watch/i/microsoft-zero-days-may-2024-30040-30051/llms.txt

## Updates (newest first)
- 2024-05-14: CVE-2024-30040 published (https://nvd.nist.gov/vuln/detail/CVE-2024-30040)
- 2024-05-14: CVE-2024-30051 published (https://nvd.nist.gov/vuln/detail/CVE-2024-30051)
- 2024-05-14: CISA added CVE-2024-30040 to the KEV catalog (federal deadline 2024-06-04) (https://www.cisa.gov/known-exploited-vulnerabilities-catalog)
- 2024-05-14: CISA added CVE-2024-30051 to the KEV catalog (federal deadline 2024-06-04) (https://www.cisa.gov/known-exploited-vulnerabilities-catalog)

## Fix brief
# Security brief: Microsoft May 2024: 2 actively exploited zero-days

Source: https://pwn.watch/i/microsoft-zero-days-may-2024-30040-30051 · status: closed (closed May 14, 2024) · severity: high · updated May 14, 2024

## Patch status
**PATCHED: fixed releases exist. Upgrade to a fixed version.**

## What it is
CVE-2024-30040: Microsoft Windows MSHTML Platform contains an unspecified vulnerability that allows for a security feature bypass. CVE-2024-30051: Microsoft DWM Core Library contains a privilege escalation vulnerability that allows an attacker to gain SYSTEM privileges. Added to the CISA KEV catalog on 2024-05-14. CISA lists known use in ransomware campaigns.

Severity detail: CVSS 8.8 (v3.1, CNA), actively exploited (CISA KEV); known ransomware use

- Product: Microsoft DWM Core Library, Windows
- CVE / advisory ids: CVE-2024-30040, CVE-2024-30051

## Affected versions
- See vendor advisory (versions are not listed in the KEV record)

## Check whether you're affected
No generic command applies (the product is a hosted service, appliance or desktop app). Check the installed version in its admin UI / About screen and compare with the versions above.

## Fix
Upgrade to one of these fixed versions (or later on the same branch):
- See vendor advisory linked in sources

After upgrading, re-run the checks above and redeploy/restart the affected services.

## Latest updates
- May 14, 2024: CVE-2024-30040 published
- May 14, 2024: CVE-2024-30051 published
- May 14, 2024: CISA added CVE-2024-30040 to the KEV catalog (federal deadline 2024-06-04)
- May 14, 2024: CISA added CVE-2024-30051 to the KEV catalog (federal deadline 2024-06-04)

## Advisories
- [Microsoft advisory: CVE-2024-30040](https://msrc.microsoft.com/update-guide/vulnerability/CVE-2024-30040) (Microsoft)
- [Microsoft advisory: CVE-2024-30051](https://msrc.microsoft.com/update-guide/vulnerability/CVE-2024-30051) (Microsoft)
- [NVD: CVE-2024-30040](https://nvd.nist.gov/vuln/detail/CVE-2024-30040) (NVD)
- [NVD: CVE-2024-30051](https://nvd.nist.gov/vuln/detail/CVE-2024-30051) (NVD)
- [CISA Known Exploited Vulnerabilities Catalog](https://www.cisa.gov/known-exploited-vulnerabilities-catalog) (CISA)

## Caveats
Derived from the CISA KEV JSON feed (catalogVersion 2026.10.21); CVSS from the CVE record (cveawg.mitre.org). startedAt is the CVE publication date when it fell in 2024 before the KEV listing, else the KEV dateAdded; exploitation may have begun earlier. closedAt is the KEV listing date (a fix or mitigation was available then unless noted).

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Machine-readable: https://pwn.watch/i/microsoft-zero-days-may-2024-30040-30051.json · all incidents: https://pwn.watch/incidents.json. Verify against the vendor advisory before changing production systems.