Track vulnerabilities like this one. Sign up free to get alerted when software you use is affected.
7.5

FreeRDP older versions can write past memory

CVE-2026-33984 · published 7 months ago
Summary

Versions of FreeRDP before 3.24.2 may let an attacker cause the program to write more data than the allocated space, potentially leading to a crash or remote code execution. The bug is fixed in version 3.24.2, so update the FreeRDP packages (including the Debian and Canonical packages) to that version or later as soon as possible.

What to do
  • Update debian freerdp3 to version 3.15.0+dfsg-2.1+deb13u2.
  • Update debian freerdp3 to version 3.24.2+dfsg-1.
Affected software
Ecosystem VendorProductAffected versions
Debian:11 debian freerdp2 All versions
Debian:12 debian freerdp2 All versions
Debian:13 debian freerdp3 < 3.15.0+dfsg-2.1+deb13u2
Fix: upgrade to 3.15.0+dfsg-2.1+deb13u2
Debian:14 debian freerdp3 < 3.24.2+dfsg-1
Fix: upgrade to 3.24.2+dfsg-1
Ubuntu:16.04:LTS canonical freerdp All versions
Ubuntu:Pro:18.04:LTS canonical freerdp2 All versions
Ubuntu:18.04:LTS canonical freerdp All versions
Ubuntu:Pro:20.04:LTS canonical freerdp2 All versions
Ubuntu:22.04:LTS canonical freerdp2 All versions
Ubuntu:24.04:LTS canonical freerdp3 All versions
Ubuntu:Pro:24.04:LTS canonical freerdp2 All versions
Ubuntu:25.10 canonical freerdp3 All versions
Ubuntu:26.04:LTS canonical freerdp3 All versions
Original advisory text
FreeRDP: ClearCodec resize_vbar_entry() Heap OOB Write
FreeRDP is a free implementation of the Remote Desktop Protocol. Prior to version 3.24.2, in resize_vbar_entry() in libfreerdp/codec/clear.c, vBarEntry->size is updated to vBarEntry->count before the winpr_aligned_recalloc() call. If realloc fails, size is inflated while pixels still points to the old, smaller buffer. On a subsequent call where count <= size (the inflated value), realloc is skipped. The caller then writes count * bpp bytes of attacker-controlled pixel data into the undersized buffer, causing a heap buffer overflow. This issue has been patched in version 3.24.2.
References
Fix within
Internet-facing 14 days
Internal At next upgrade
  • Not known to be exploited
  • Needs hands-on effort to exploit
  • Gives an attacker full control
Severity
7.5 High
Exploitation
<1% chance of attack within 30 days
Type
CWE-122Heap-based Buffer Overflow
CWE-131Incorrect Calculation of Buffer Size
Timeline
Published30 Mar 2026
Updated4 Nov 2026
First seen26 Mar 2026
Sources
DEBIAN-CVE-2026-33984 · OSV
CVE-2026-33984 · NVD
CVE-2026-33984 · OSV
GHSA-8469-2xcx-frf6 · GHSA
UBUNTU-CVE-2026-33984 · OSV
Track software like this
Free during beta