CVE-2026-33986 | FreeRDP: H.264 YUV Buffer Dimension Desync - Heap OOB Write

FreeRDP is a free implementation of the Remote Desktop Protocol. Prior to version 3.24.2, in yuv_ensure_buffer() in libfreerdp/codec/h264.c, h264->width and h264->height are updated before the reallocation loop. If any winpr_aligned_recalloc() call fails, the function returns FALSE but width/height are already inflated. This issue has been patched in version 3.24.2.

Published: 2026-03-30 Last update: 2026-04-01 Assigner: [email protected] Source: [email protected]
NVD Status：Analyzed，CVE State: published
View at NVD, CVE.org, EUVD

CVE-2026-33986 is rated Low Risk (36.2/100): CVSS High severity, with low exploitation likelihood (EPSS 0.06%). Monitor for updates and reassess as exploit intelligence or EPSS changes.

Risk is dynamic; we continuously reassess and refresh what is shown on this page as upstream context changes.

Exploit prediction scoring system (EPSS) score for CVE-2026-33986

EPSS lead: Daily EPSS estimates relative likelihood of exploitation; percentile ranks this CVE among scored vulnerabilities (higher = more severe relative rank).

# Date Old EPSS score New EPSS score Delta (New - Old)
1 2026-06-06 0.05% 0.06% +0.01%
2 2026-05-24 0.06% 0.05% -0.01%
3 2026-05-22 — 0.06% —

Full EPSS history (4 records total)

Common vulnerability scoring system (CVSS) metrics for CVE-2026-33986

CVSS metrics for this CVE.

Base score Version Severity Vector Exploitability Impact Score source
7.5 3.1 HIGH
CVSS:3.1/AV:N/AC:H/PR:N/UI:R/S:U/C:H/I:H/A:H Click to expand
Attack vector (AV:N)
Could be attacked over the internet or any normal routed network—not just someone sitting at the machine.
Attack complexity (AC:H)
Even with access, the exploit needs extra luck, timing, or a fussy environment to actually work.
Privileges required (PR:N)
No account or special rights needed—anonymous or random user is enough.
User interaction (UI:R)
A real person has to do something—click, install, enable—otherwise it doesn’t land.
Scope (S:U)
Damage stays in the same “trust bubble” as the broken component—no big spill into unrelated systems.
Confidentiality (C:H)
Serious risk that confidential data gets exposed in a big way.
Integrity (I:H)
They could widely tamper with or forge data—trust in the data is badly hurt.
Availability (A:H)
Could take the service down hard or make it unusable for people who depend on it.
 1.6 5.9 [email protected]

Weakness enumeration for CVE-2026-33986

OS Trackers for CVE-2026-33986

vendor priority summary link
alpine — CVE-2026-33986: 1 source package rows (freerdp); 33 state rows across 2 repos (3.23-community, edge-community); fixed 2, open 31. https://security.alpinelinux.org/vuln/CVE-2026-33986
debian not yet assigned CVE-2026-33986 not yet assigned priority: Debian including 2 source packages (freerdp2, freerdp3), 5 status rows across 5 suites (bookworm, bullseye, forky, sid, trixie): resolved 3, open 2. https://security-tracker.debian.org/tracker/CVE-2026-33986
redhat high — https://access.redhat.com/security/cve/CVE-2026-33986
suse high CVE-2026-33986 severity important: SUSE including 23 source package names (freerdp, freerdp-devel, …), 43 product×package rows across 5 product lines (SUSE Linux Enterprise Module for Package Hub 15 SP7, SUSE Linux Enterprise Server 12 SP5-LTSS, … (5 product lines)): Known Not Affected 43. https://www.suse.com/security/cve/CVE-2026-33986/
ubuntu medium CVE-2026-33986 medium priority: Ubuntu including 3 source packages (freerdp, freerdp2, freerdp3), 16 status rows across 7 suites (bionic, focal, jammy, noble, questing, upstream, xenial): needs-triage 10, DNE 5, released 1. https://ubuntu.com/security/CVE-2026-33986

Affected software / configurations for CVE-2026-33986

Vendor Product Version Raw CPE
freerdp freerdp < 3.24.2 cpe:2.3:a:freerdp:freerdp:*:*:*:*:*:*:*:*

References for CVE-2026-33986

cvelogic Threat Intelligence