Skip to content
Noroxi
CVE-2026-33983· NVD / CVE Program· CNA GitHub_M

FreeRDP: Progressive Codec Quant BYTE Underflow - UB + CPU DoS

FreeRDP is a free implementation of the Remote Desktop Protocol. Prior to version 3.24.2, progressive_decompress_tile_upgrade() detects a mismatch via progressive_rfx_quant_cmp_equal() but only emits WLog_WARN, execution continues. The wrapped value (247) is used as a shift exponent, causing undefined behavior and an approximately 80 billion iteration loop (CPU DoS). This issue has been patched in version 3.24.2.

MediumCVSS 6.5 · v3.1—No exploit Fix available
Published
Mar 30, 2026
Updated
Jul 15, 2026
EPSS
0.8% · 55th percentile
Follow this CVE

Sign in to follow · You’ll be notified if a followed record enters KEV, gets an exploit or is updated.

Report tools

JSON

Action score

26

Monitor

Low priority for now.

CVSS
26 / 40 · 6.5 / 10
CISA KEV
0 / 30 · Not listed
EPSS
0 / 30 · 0.8%

CISA SSVC decision

Exploitation
none
Automatable
no
Technical impact
partial

Vulnrichment: CISA's decision-tree inputs.

CNA vs NVD score

NVD
—
CNA · GitHub_M
6.5
NVD has not scored this yet; the score shown is the CNA’s.

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

Noroxi analysis

No Noroxi analysis for this record yet

We don't hand-write analysis for the hundreds of thousands of vulnerabilities in the database; that wouldn't be honest. For notable, high-impact vulnerabilities our team writes the mechanism, detection and remediation steps.

We use this product, ask for help

Affected systems

VendorProduct
freerdpfreerdp

Affected versions

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

  • freerdp freerdpbefore 3.24.2

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

    • < 3.24.2affected

Package-level exposure

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

EcosystemPackageAffected rangeFix
AlmaLinux:10freerdpbefore 2:3.10.3-5.el10_1.62:3.10.3-5.el10_1.6
AlmaLinux:10freerdp-develbefore 2:3.10.3-5.el10_1.62:3.10.3-5.el10_1.6
AlmaLinux:10freerdp-libsbefore 2:3.10.3-5.el10_1.62:3.10.3-5.el10_1.6
AlmaLinux:10freerdp-serverbefore 2:3.10.3-5.el10_1.62:3.10.3-5.el10_1.6
AlmaLinux:10libwinprbefore 2:3.10.3-5.el10_1.62:3.10.3-5.el10_1.6
AlmaLinux:10libwinpr-develbefore 2:3.10.3-5.el10_1.62:3.10.3-5.el10_1.6
AlmaLinux:8freerdpbefore 2:2.11.7-7.el8_102:2.11.7-7.el8_10
AlmaLinux:8freerdp-develbefore 2:2.11.7-7.el8_102:2.11.7-7.el8_10
AlmaLinux:8freerdp-libsbefore 2:2.11.7-7.el8_102:2.11.7-7.el8_10
AlmaLinux:8libwinprbefore 2:2.11.7-7.el8_102:2.11.7-7.el8_10
AlmaLinux:8libwinpr-develbefore 2:2.11.7-7.el8_102:2.11.7-7.el8_10
AlmaLinux:9freerdpbefore 2:2.11.7-1.el9_7.62:2.11.7-1.el9_7.6
AlmaLinux:9freerdp-develbefore 2:2.11.7-1.el9_7.62:2.11.7-1.el9_7.6
AlmaLinux:9freerdp-libsbefore 2:2.11.7-1.el9_7.62:2.11.7-1.el9_7.6
AlmaLinux:9libwinprbefore 2:2.11.7-1.el9_7.62:2.11.7-1.el9_7.6
AlmaLinux:9libwinpr-develbefore 2:2.11.7-1.el9_7.62:2.11.7-1.el9_7.6
Debian:12freerdp2all versions—
Debian:13freerdp3before 3.15.0+dfsg-2.1+deb13u23.15.0+dfsg-2.1+deb13u2
Debian:14freerdp3before 3.24.2+dfsg-13.24.2+dfsg-1
openSUSE:Tumbleweedfreerdpbefore 3.24.2-1.13.24.2-1.1
Red Hat:enterprise_linux_eus:10.0freerdpbefore 2:3.10.3-3.el10_0.62:3.10.3-3.el10_0.6
Red Hat:enterprise_linux_eus:10.0freerdp-debuginfobefore 2:3.10.3-3.el10_0.62:3.10.3-3.el10_0.6
Red Hat:enterprise_linux_eus:10.0freerdp-debugsourcebefore 2:3.10.3-3.el10_0.62:3.10.3-3.el10_0.6
Red Hat:enterprise_linux_eus:10.0freerdp-develbefore 2:3.10.3-3.el10_0.62:3.10.3-3.el10_0.6

+96

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 gdi_Bitmap_Decompress
    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 co
    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 update_read_bitmap_
    41Plan
  • CVE-2018-8785FreeRDP prior to version 2.0.0-rc4 contains a Heap-Based Buffer Overflow in function zgfx_decompress() that results in a memory corruption a
    41Plan
  • CVE-2018-8784FreeRDP prior to version 2.0.0-rc4 contains a Heap-Based Buffer Overflow in function zgfx_decompress_segment() that results in a memory corr
    41Plan
  • CVE-2024-32460FreeRDP Out-Of-Bounds Read in interleaved_decompress
    40Plan

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 FreeRDP3.24.2 · descriptionVendor (CNA)
almalinux:freerdp2:2.11.7-1.el9_7.6 · AlmaLinux:9Package registry (OSV)
almalinux:freerdp-devel2:2.11.7-1.el9_7.6 · AlmaLinux:9Package registry (OSV)
almalinux:freerdp-libs2:2.11.7-1.el9_7.6 · AlmaLinux:9Package registry (OSV)
almalinux:freerdp-server2:3.10.3-5.el10_1.6 · AlmaLinux:10Package registry (OSV)
almalinux:libwinpr2:2.11.7-1.el9_7.6 · AlmaLinux:9Package registry (OSV)
almalinux:libwinpr-devel2:2.11.7-1.el9_7.6 · AlmaLinux:9Package registry (OSV)
debian:freerdp33.15.0+dfsg-2.1+deb13u2 · Debian:13Package registry (OSV)
opensuse:freerdp3.24.2-1.1 · openSUSE:TumbleweedPackage registry (OSV)
red hat:freerdp2:2.11.2-1.el9_4.6 · Red Hat:rhel_eus:9.4::appstreamPackage registry (OSV)
red hat:freerdp-debuginfo2:2.11.2-1.el9_4.6 · Red Hat:rhel_eus:9.4::appstreamPackage registry (OSV)
red hat:freerdp-debugsource2:2.11.2-1.el9_4.6 · Red Hat:rhel_eus:9.4::appstreamPackage registry (OSV)
red hat:freerdp-devel2:2.11.2-1.el9_4.6 · Red Hat:rhel_eus:9.4::crbPackage registry (OSV)
red hat:freerdp-libs2:2.11.2-1.el9_4.6 · Red Hat:rhel_eus:9.4::appstreamPackage registry (OSV)
red hat:freerdp-libs-debuginfo2:2.11.2-1.el9_4.6 · Red Hat:rhel_eus:9.4::appstreamPackage registry (OSV)
red hat:freerdp-server2:3.10.3-3.el10_0.6 · Red Hat:enterprise_linux_eus:10.0Package registry (OSV)
red hat:freerdp-server-debuginfo2:3.10.3-3.el10_0.6 · Red Hat:enterprise_linux_eus:10.0Package registry (OSV)
red hat:libwinpr2:2.11.2-1.el9_4.6 · Red Hat:rhel_eus:9.4::appstreamPackage registry (OSV)
red hat:libwinpr-debuginfo2:2.11.2-1.el9_4.6 · Red Hat:rhel_eus:9.4::appstreamPackage registry (OSV)
red hat:libwinpr-devel2:2.11.2-1.el9_4.6 · Red Hat:rhel_eus:9.4::crbPackage registry (OSV)
rocky linux:freerdp2:2.11.7-1.el9_7.6 · Rocky Linux:9Package registry (OSV)
suse:freerdp3.10.3-150700.3.17.1 · SUSE:Linux Enterprise Module for Package Hub 15 SP7Package 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.

Credits

All researchers

Finders, reporters and analysts named in the CNA record. Click a name for that researcher’s other records.

No credits in the CNA record.

Variant candidates

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

  • CVE-2026-2795133 days apartFreeRDP has possible Integer overflow in Stream_EnsureCapacity
    30Monitor
  • CVE-2026-91960169 days apartFreeRDP before 3.31.0 Integer Overflow Double Free
    28Monitor
  • CVE-2026-55648142 days apartFreeRDP: Integer Overflow in `freerdp_image_copy_from_icon_data` Bypasses Bounds Check
    24Monitor
  • CVE-2026-2977617 days apartFreeRDP has an Integer Underflow in update_read_cache_bitmap_order Function of FreeRDP's Core Library
    12Monitor

Chain candidates

An authentication bypass and a privilege-requiring bug in the same product, published close together: combined they may become an unauthenticated path.

—

Bug bounty scope

No known public program.

Source: bounty-targets-data (public HackerOne, Bugcrowd, Intigriti, YesWeHack listings).

Technical details

Attack conditions

  • Anyone who can reach it over the internet can trigger it.
  • No account or password is required.
  • A user must open a link or visit a page.
  • No special conditions are required; it is repeatable.

If successful

Confidentiality
none
Integrity
none
Availability
high · the service can be disrupted
Attack vector
Network
Attack complexity
Low
Privileges required
None
User interaction
Required
Scope
Unchanged
Confidentiality impact
None
Integrity impact
None
Availability impact
High

Weakness class (CWE)

CWE-190 · Integer Overflow or Wraparound

CVSS vector

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

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.

ATT&CK techniques

—

Change log

  1. Fix✗ → ✓

For records you follow, these changes also arrive as notifications. →

References

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

All records