CVE-2026-64621: Freerdp double free (CVSS 7.3)

Description

FreeRDP before 3.28.0 (affected 3.x through 3.27.1) contains a double-free vulnerability in freerdp_client_rdp_file_apply_to_settings() (client/common/file.c) when parsing the selectedmonitors field of a .rdp connection file. The MonitorIds array is allocated through the settings object, and a raw non-owning pointer to it is freed on the strtoul error path without clearing settings->MonitorIds, leaving it dangling; at teardown freerdp_settings_free() frees the same buffer again. An attacker who convinces a victim to open a crafted .rdp file with oversized monitor tokens can trigger a size-controlled double-free in any FreeRDP CLI client (xfreerdp/sdl-freerdp/wlfreerdp) in the default configuration.

CVSS 3.1 breakdown

Attack vectorLocal

Attack complexityLow

Privileges requiredNone

User interactionRequired

ScopeUnchanged

ConfidentialityLow

IntegrityHigh

AvailabilityHigh

CVSS:3.1/AV:L/AC:L/PR:N/UI:R/S:U/C:L/I:H/A:H

Affected products

Freerdp≥ 3.0.0 < 3.28.0

Remediation

Fixed in

Freerdp≥ 3.28.0

Patch & vendor advisories

References

https://github.com/FreeRDP/FreeRDP/commit/1f7a716d39b5605bb8a83b0c3c97a6ce386609efPatch
https://github.com/FreeRDP/FreeRDP/security/advisories/GHSA-f27x-frr8-j9hcExploitMitigationVendor Advisory
https://www.vulncheck.com/advisories/freerdp-before-double-free-via-selectedmonitorsPatchThird Party Advisory

Related CVEs

Recent high-severity vulnerabilities sharing a weakness type.

Frequently asked

Is CVE-2026-64621 being actively exploited?

CVE-2026-64621 is not in the CISA KEV catalog. A public exploit reference exists, so treat it as exploitable. Its EPSS exploit probability is 0.36%.

How severe is CVE-2026-64621?

CVE-2026-64621 has a CVSS 3.1 base score of 7.3, rated high. EPSS estimates a 0.36% probability of exploitation.

Which products are affected by CVE-2026-64621?

Affected products include Freerdp.

How do I fix CVE-2026-64621?

Upgrade affected software to a fixed version, for example Freerdp 3.28.0 or later, then confirm no affected versions remain in your inventory.

How Secuno handles this

Secuno correlates vulnerabilities like CVE-2026-64621 against the real software inventory on every managed device, every day. Rather than a static severity, each match is scored in context: exploit availability, EPSS, the asset's exposure, and business criticality decide where it lands in the queue. If an affected version is present anywhere across your portfolio, it surfaces automatically with a prioritised remediation path.

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