CVE-2025-24990: Microsoft Windows Untrusted Pointer Dereference Vulnerability

Should you act?

Exploited: patch now if you run it

CISA has confirmed exploitation in the wild. This signal is computed from CISA KEV, EPSS and CVSS data; it is not an editorial verdict.

• Yes, if you run Microsoft Windows. CISA added this CVE to its Known Exploited Vulnerabilities catalog on 2025-10-14, which means there is reliable evidence of exploitation in the wild. US federal agencies must remediate by 2025-11-04; treat that as the outer limit, not the target.
• EPSS 6.4%, percentile 94: FIRST’s model estimates a 6.4% chance of exploitation activity in the next 30 days, higher than 94% of all scored CVEs (elevated). EPSS is a probability, not a verdict.
• Needs local access needed. Lower urgency for most teams unless an attacker could already run code on the machine.

What it is

Microsoft is aware of vulnerabilities in the third party Agere Modem driver that ships natively with supported Windows operating systems. This is an announcement of the upcoming removal of ltmdm64.sys driver. The driver has been removed in the October cumulative update. Fax modem hardware dependent on this specific driver will no longer work on Windows. Microsoft recommends removing any existing dependencies on this hardware.

CISA’s summary

Microsoft Windows Agere Modem Driver contains an untrusted pointer dereference vulnerability that allows for privilege escalation. An attacker who successfully exploited this vulnerability could gain administrator privileges.

Weakness type: CWE-822.

Product: Microsoft Windows · Assigned by: microsoft · Published: 2025-10-14

Affected and fixed versions

Severity scores

• Attack vector: local access needed
• Attack complexity: low
• Privileges required: low (any account)
• User interaction: none
• Scope: unchanged

CVSS measures how bad a flaw is if exploited, not how likely exploitation is. Read it next to the exploitation data below.

Exploitation and urgency

• CISA KEV: added 2025-10-14; federal due date 2025-11-04. Known ransomware use: Unknown.
• 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.
• CISA SSVC assessment: exploitation active, automatable no, technical impact total.
• FIRST EPSS (model of 2026-10-21): 6.37% probability of exploitation activity in the next 30 days; percentile 94.

Timeline

• 2025-10-14 — Added to CISA’s Known Exploited Vulnerabilities catalog
• 2025-10-14 — CVE record published by microsoft
• 2025-11-04 — CISA remediation deadline for US federal agencies
• 2026-02-26 — CVE record last updated

Sources and references

Original sources first. Version and fix details should always be confirmed against the vendor or project advisory.

Vendor and project advisories, patches

1. Windows Agere Modem Driver Elevation of Privilege Vulnerability msrc.microsoft.com
2. Listed in CISA KEV notes (msrc.microsoft.com) msrc.microsoft.com

Vulnerability records

1. CVE.org record CVE-2025-24990 cve.org
2. NVD entry CVE-2025-24990 nvd.nist.gov

Government

1. CISA Known Exploited Vulnerabilities catalog entry cisa.gov

Other references from the CVE record and advisory

1. vicarius.io vicarius.io
2. vicarius.io vicarius.io

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