CVE intelligence

CVE-2026-19499

Vulnerability intelligence

Published Sep 14, 2026Sources checked Oct 27, 2026

7.7HIGHCVSS out of 10

What this means

Review the available evidence

CVE-2026-19499 and is rated High severity with a CVSS score of 7.7. It is not in the current CISA KEV record we collected. That does not prove exploitation has not occurred.

What to do next

Remediation and response

Microsoft Security Response Center guidance

Vendor revision: Sep 25, 2026

Release Notes

Ubuntu Security Notices guidance

Vendor revision: Sep 10, 2026

USN-8737-1 fixed vulnerabilities in GNU C Library.

CISA KEVNot listedBased on the latest collected catalog

EPSS0.3%Estimated 30-day exploitation probability

Ransomware useNot markedCISA KEV ransomware field

Threat actors0Source-linked actor relationships

Overview

What is CVE-2026-19499?

Calling strfmon and strfmon_l in the GNU C Library version 2.38 to 2.44 can write past the end of the caller-supplied output buffer when a conversion uses right-justified width padding.

Exploitation requires an application code path that calls strfmon or strfmon_l with right-justified width padding into a destination buffer that is large enough for the padding to succeed but too small for the internal memmove call. The field width or format may be attacker-influenced or a fixed susceptible pattern in the caller.

At the time of publication, no network-facing application impact is known.

Source: NVD