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NVD / CVE Program· CNA GitHub_M

CVE-2026-63652: FreeRDP: Double-free of `client_formats` in the rdpsnd server channel on a malformed Client Audio Formats PDU

HighCVSS 7.1 · v4.0—No exploit Fix available

Noroxi assessment

Priority: Monitor (action score 28/100)

  • The sources we track (CISA KEV, Exploit-DB, Metasploit, Nuclei, GitHub) show no public exploit code or exploitation in the wild.
  • Probability of exploitation in the next 30 days: 0.58% (FIRST EPSS).
  • Anyone who can reach it over the internet can trigger it. A low-privileged account is enough. No user action is required. No special conditions are required; it is repeatable.
  • Fixed version: FreeRDP FreeRDP 3.28.0.

Low priority for now. Upgrade to FreeRDP FreeRDP 3.28.0 or later.

Generated automatically from the record's data: CVSS (NVD and CNA), CISA KEV and SSVC, FIRST EPSS, exploit sources, fixed versions. How we calculate it

Primary sources: NVD · CVE.org · FIRST EPSS

FreeRDP is a free implementation of the Remote Desktop Protocol. Prior to 3.28.0, rdpsnd_server_recv_formats in channels/rdpsnd/server/rdpsnd_main.c frees context->client_formats on a malformed Client Audio Formats PDU without clearing the owning pointer or num_client_formats. An authenticated RDP client can trigger an error such as a cbSize larger than the remaining record, leave the dangling pointer in the server context, and cause rdpsnd_server_context_free to free the same allocation again at session teardown. This reliably terminates the server and can create allocator-dependent heap corruption. This issue is fixed in version 3.28.0.

Published
Aug 19, 2026
Updated
Oct 26, 2026
EPSS
0.5% · 48th percentile

Report tools

JSON

Action score

28

Monitor

Low priority for now.

CVSS
28 / 40 · 7.1 / 10
CISA KEV
0 / 30 · Not listed
EPSS
0 / 30 · 0.5%

CISA SSVC decision

Exploitation
proof of concept
Automatable
no
Technical impact
partial

Vulnrichment: CISA's decision-tree inputs.

CNA vs NVD score

NVD
—
CNA · GitHub_M
7.1
NVD has not scored this yet; the score shown is the CNA’s.

CVSS:4.0/AV:N/AC:L/AT:N/PR:L/UI:N/VC:N/VI:N/VA:H/SC:N/SI:N/SA:N

The score given by the assigning authority versus NVD’s independent score. A gap means the severity is contested.

Get told when this record changes

  • Not in KEV: no record of exploitation in the wild
  • No public exploit code on record
  • A fix has been released

If any of these changes, we'll tell you in the daily email digest.

Follow CVE-2026-63652

When you'll hear from us

  • when it enters CISA KEV
  • when exploit code appears or is weaponized
  • when the record is updated (including a fixed version)
  • when EPSS rises 20 points in a week

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Noroxi analysis

What does it mean in your environment?

The assessment above is generated automatically from the record's data; it doesn't know your environment. Our team verifies on your systems whether this vulnerability is actually exploitable and which mitigation is enough.

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Affected systems

Is your version affected?

Pick the product and type the version you run. It's compared with this record's version ranges in your browser; the version isn't sent anywhere.

VendorProduct
freerdpfreerdp

Versions reported by the vendor

Affected version ranges reported by the assigning authority (GitHub_M). Independent of NVD's CPE analysis and usually ahead of it.

  • FreeRDP FreeRDP

    • < 3.28.0affected

Affected versions

NVD version ranges (for catalog products). Add the product to your stack with a version and matching uses these.

  • freerdp freerdpbefore 3.28.0

Package-level exposure

OSV and GitHub Advisory data: ecosystem, package and range. SBOM matching uses this table.

EcosystemPackageAffected rangeFix
AlmaLinux:10freerdpbefore 2:3.10.3-12.el10_2.102:3.10.3-12.el10_2.10
AlmaLinux:10freerdp-develbefore 2:3.10.3-12.el10_2.102:3.10.3-12.el10_2.10
AlmaLinux:10freerdp-libsbefore 2:3.10.3-12.el10_2.102:3.10.3-12.el10_2.10
AlmaLinux:10freerdp-serverbefore 2:3.10.3-12.el10_2.102:3.10.3-12.el10_2.10
AlmaLinux:10libwinprbefore 2:3.10.3-12.el10_2.102:3.10.3-12.el10_2.10
AlmaLinux:10libwinpr-develbefore 2:3.10.3-12.el10_2.102:3.10.3-12.el10_2.10
Debian:12freerdp2from 0—
Debian:13freerdp3from 0—
Debian:14freerdp3before 3.28.0+dfsg-13.28.0+dfsg-1
openSUSE:Tumbleweedfreerdpbefore 3.30.0-1.13.30.0-1.1
Red Hat:enterprise_linux_eus:10.0freerdpbefore 2:3.10.3-3.el10_0.162:3.10.3-3.el10_0.16
Red Hat:enterprise_linux_eus:10.0freerdp-debuginfobefore 2:3.10.3-3.el10_0.162:3.10.3-3.el10_0.16
Red Hat:enterprise_linux_eus:10.0freerdp-debugsourcebefore 2:3.10.3-3.el10_0.162:3.10.3-3.el10_0.16
Red Hat:enterprise_linux_eus:10.0freerdp-develbefore 2:3.10.3-3.el10_0.162:3.10.3-3.el10_0.16
Red Hat:enterprise_linux_eus:10.0freerdp-libsbefore 2:3.10.3-3.el10_0.162:3.10.3-3.el10_0.16
Red Hat:enterprise_linux_eus:10.0freerdp-libs-debuginfobefore 2:3.10.3-3.el10_0.162:3.10.3-3.el10_0.16
Red Hat:enterprise_linux_eus:10.0freerdp-serverbefore 2:3.10.3-3.el10_0.162:3.10.3-3.el10_0.16
Red Hat:enterprise_linux_eus:10.0freerdp-server-debuginfobefore 2:3.10.3-3.el10_0.162:3.10.3-3.el10_0.16
Red Hat:enterprise_linux_eus:10.0libwinprbefore 2:3.10.3-3.el10_0.162:3.10.3-3.el10_0.16
Red Hat:enterprise_linux_eus:10.0libwinpr-debuginfobefore 2:3.10.3-3.el10_0.162:3.10.3-3.el10_0.16
Red Hat:enterprise_linux_eus:10.0libwinpr-develbefore 2:3.10.3-3.el10_0.162:3.10.3-3.el10_0.16
Red Hat:enterprise_linux:10.2freerdpbefore 2:3.10.3-12.el10_2.102:3.10.3-12.el10_2.10
Red Hat:enterprise_linux:10.2freerdp-debuginfobefore 2:3.10.3-12.el10_2.102:3.10.3-12.el10_2.10
Red Hat:enterprise_linux:10.2freerdp-debugsourcebefore 2:3.10.3-12.el10_2.102:3.10.3-12.el10_2.10

+9

Same product

freerdp: all records

Other highest-scoring records for the same primary product.

  • CVE-2018-8787FreeRDP prior to version 2.0.0-rc4 contains an Integer Overflow that leads to a Heap-Based Buffer Overflow in function…
    42Plan
  • CVE-2018-8788FreeRDP prior to version 2.0.0-rc4 contains an Out-Of-Bounds Write of up to 4 bytes in function nsc_rle_decode() that results in a memory…
    41Plan
  • CVE-2018-8786FreeRDP prior to version 2.0.0-rc4 contains an Integer Truncation that leads to a Heap-Based Buffer Overflow in function…
    41Plan

Published before and after this one in the same product

  • ← EarlierCVE-2026-63117Aug 19, 2026 · FreeRDP: Denial of service through ADPCM frame size calculation
    26Monitor
  • ← EarlierCVE-2026-63633Aug 19, 2026 · FreeRDP: Heap buffer overflow in Opus audio decode (`freerdp_dsp_decode_opus` resizes the wrong stream) — server→client
    30Monitor
  • Later →CVE-2026-85089Sep 3, 2026 · FreeRDP before 3.31.0 Information Disclosure via uninitialized heap memory
    28Monitor

Remediation

Which version to upgrade to

Fix versions compiled from the vendor, package registries and Microsoft. Verify the vendor's note before upgrading.

Product / packageFixed versionSource
FreeRDP FreeRDP3.28.0 · descriptionVendor (CNA)
almalinux:freerdp2:3.10.3-12.el10_2.10 · AlmaLinux:10Package registry (OSV)
almalinux:freerdp-devel2:3.10.3-12.el10_2.10 · AlmaLinux:10Package registry (OSV)
almalinux:freerdp-libs2:3.10.3-12.el10_2.10 · AlmaLinux:10Package registry (OSV)
almalinux:freerdp-server2:3.10.3-12.el10_2.10 · AlmaLinux:10Package registry (OSV)
almalinux:libwinpr2:3.10.3-12.el10_2.10 · AlmaLinux:10Package registry (OSV)
almalinux:libwinpr-devel2:3.10.3-12.el10_2.10 · AlmaLinux:10Package registry (OSV)
debian:freerdp33.28.0+dfsg-1 · Debian:14Package registry (OSV)
opensuse:freerdp3.30.0-1.1 · openSUSE:TumbleweedPackage registry (OSV)
red hat:freerdp2:3.10.3-12.el10_2.10 · Red Hat:enterprise_linux:10.2Package registry (OSV)
red hat:freerdp-debuginfo2:3.10.3-12.el10_2.10 · Red Hat:enterprise_linux:10.2Package registry (OSV)
red hat:freerdp-debugsource2:3.10.3-12.el10_2.10 · Red Hat:enterprise_linux:10.2Package registry (OSV)
red hat:freerdp-devel2:3.10.3-12.el10_2.10 · Red Hat:enterprise_linux:10.2Package registry (OSV)
red hat:freerdp-libs2:3.10.3-12.el10_2.10 · Red Hat:enterprise_linux:10.2Package registry (OSV)
red hat:freerdp-libs-debuginfo2:3.10.3-12.el10_2.10 · Red Hat:enterprise_linux:10.2Package registry (OSV)
red hat:freerdp-server2:3.10.3-12.el10_2.10 · Red Hat:enterprise_linux:10.2Package registry (OSV)
red hat:freerdp-server-debuginfo2:3.10.3-12.el10_2.10 · Red Hat:enterprise_linux:10.2Package registry (OSV)
red hat:libwinpr2:3.10.3-12.el10_2.10 · Red Hat:enterprise_linux:10.2Package registry (OSV)
red hat:libwinpr-debuginfo2:3.10.3-12.el10_2.10 · Red Hat:enterprise_linux:10.2Package registry (OSV)
red hat:libwinpr-devel2:3.10.3-12.el10_2.10 · Red Hat:enterprise_linux:10.2Package registry (OSV)
rocky linux:freerdp2:3.10.3-12.el10_2.10 · Rocky Linux:10Package registry (OSV)

Exploit status

No known public exploit

No public exploit has been observed yet. That doesn't mean you're safe, only that the bar is a little higher.

Research context

For pentesters and researchers: attack profile, score disagreement, timeline, patch commits, credits, variant and chain candidates, bug bounty scope. All derived from existing data; no exploit code.

Timeline

From publication to today: proof of concept, Metasploit module, CISA KEV and fix record. Dates are as reported by the sources.

No dated events beyond publication.

EPSS, last 120 days

FIRST EPSS daily score; only changes of 0.01 or more are recorded (step chart).

Patch and commit links

Commit, PR and diff links among the references. A starting point for patch-diffing and variant hunting; fixes, not exploits.

Variant candidates

Same product, same weakness class, within 18 months. If the patch missed the root cause, the sibling bug is here.

  • CVE-2026-6462130 days apartFreeRDP before 3.28.0 Double-Free via selectedmonitors
    37Monitor
  • CVE-2026-4442282 days apartFreeRDP RDPEAR NDR ref-id aliasing causes client-side UAF/double-free and type confusion
    35Monitor
  • CVE-2026-12195677 days apartFreeRDP before 3.32.2 Double Free in WinPR Kerberos retrieveSomeTgt
    34Monitor
  • CVE-2026-10925754 days apartFreeRDP before 3.32.0 Double Free via NSCodec plane growth failure
    32Monitor
  • CVE-2026-10994355 days apartFreeRDP 3.29.0 before 3.32.0 Double Free via Async-Update Polygon Order
    28Monitor
  • CVE-2026-33995142 days apartFreeRDP: Possible double free in kerberos_AcceptSecurityContext
    21Monitor

Not on record for this CVE: researcher credit · public bounty program.

Technical details

Attack conditions

  • Anyone who can reach it over the internet can trigger it.
  • A low-privileged account is enough.
  • No user action is required.
  • No special conditions are required; it is repeatable.

If successful

Confidentiality
Integrity
Availability
Attack vector
Network
Attack complexity
Low
Privileges required
Low
User interaction
None
Scope
X

Weakness class (CWE)

CWE-415 · Double Free

CVSS vector

CVSS:4.0/AV:N/AC:L/AT:N/PR:L/UI:N/VC:N/VI:N/VA:H/SC:N/SI:N/SA:N/E:X/CR:X/IR:X/AR:X/MAV:X/MAC:X/MAT:X/MPR:X/MUI:X/MVC:X/MVI:X/MVA:X/MSC:X/MSI:X/MSA:X/S:X/AU:X/R:X/V:X/RE:X/U:X

nvd-secondary

Attack context

MITRE CAPEC attack patterns and ATT&CK techniques for this weakness class (CWE). A starting point for detection rules and threat hunting.

MITRE has no CAPEC/ATT&CK mapping for this CWE.

References

Show all references (2 more)

Vendor advisories and official records. Exploit/PoC links are deliberately left out.

All records