CVE-2026-2045: GIMP XWD File Parsing RCE Vulnerability

CVE-2026-2045 Overview

CVE-2026-2045 is an out-of-bounds write vulnerability affecting GIMP's XWD file parsing functionality. This vulnerability allows remote attackers to execute arbitrary code on affected installations of GIMP. User interaction is required to exploit this vulnerability, as the target must visit a malicious page or open a malicious file.

The specific flaw exists within the parsing of XWD (X Window Dump) files. The issue results from the lack of proper validation of user-supplied data, which can result in a write past the end of an allocated buffer. An attacker can leverage this vulnerability to execute code in the context of the current process.

Critical Impact

Successful exploitation allows attackers to execute arbitrary code with the privileges of the GIMP process, potentially leading to complete system compromise through crafted XWD image files.

Affected Products

• GIMP version 3.0.6
• GIMP installations with XWD file import functionality enabled
• Systems where users may open untrusted image files

Discovery Timeline

• 2026-02-20 - CVE-2026-2045 published to NVD
• 2026-02-24 - Last updated in NVD database

Technical Details for CVE-2026-2045

Vulnerability Analysis

This vulnerability is classified as CWE-787 (Out-of-Bounds Write), a memory corruption flaw that occurs when GIMP's XWD file parser fails to properly validate user-supplied data before writing to memory. XWD files are X Window Dump image format files commonly used in Unix/Linux environments.

When GIMP parses a maliciously crafted XWD file, the application writes data beyond the bounds of an allocated buffer. This memory corruption can be exploited to overwrite adjacent memory structures, potentially allowing an attacker to redirect program execution to attacker-controlled code.

The vulnerability requires local access in the sense that a user must be convinced to open a malicious file. However, this can be achieved through various attack vectors including email attachments, malicious downloads, or compromised websites serving crafted XWD images. The attack complexity is low, requiring no special privileges, though user interaction is mandatory.

Root Cause

The root cause of CVE-2026-2045 lies in insufficient bounds checking within GIMP's XWD file parsing routines. When processing XWD image headers and pixel data, the parser does not adequately validate that the specified dimensions and data offsets are within safe boundaries before performing memory write operations. This allows specially crafted XWD files to specify values that cause writes beyond allocated buffer space.

Attack Vector

The attack vector for this vulnerability involves crafting a malicious XWD image file with manipulated header values or pixel data that triggers the out-of-bounds write condition. An attacker would typically:

1. Create a specially crafted XWD file with manipulated metadata values designed to overflow buffer boundaries
2. Deliver the malicious file to victims via email attachments, malicious downloads, or compromised websites
3. When the victim opens the file in GIMP, the parser processes the malformed data
4. The out-of-bounds write corrupts memory, potentially allowing arbitrary code execution in the context of the GIMP process

The vulnerability was tracked as ZDI-CAN-28265 by the Zero Day Initiative before receiving its CVE designation. Technical details are available in the Zero Day Initiative Advisory ZDI-26-119.

Detection Methods for CVE-2026-2045

Indicators of Compromise

• Unexpected GIMP crashes when opening XWD format image files
• Memory access violations or segmentation faults in GIMP process logs
• Suspicious XWD files with abnormal header values or unusually large dimension specifications
• Unexpected child processes spawned from the GIMP application

Detection Strategies

• Monitor file system activity for XWD file downloads from untrusted sources
• Implement application whitelisting to detect unusual process behavior from GIMP
• Deploy endpoint detection and response (EDR) solutions capable of identifying memory corruption exploitation attempts
• Configure SIEM rules to alert on GIMP process anomalies such as unexpected network connections or file writes

Monitoring Recommendations

• Enable verbose logging for image processing applications to capture parsing errors
• Monitor for unusual memory allocation patterns in GIMP processes
• Implement file integrity monitoring for XWD files in shared directories
• Deploy network monitoring to detect potential delivery of malicious image files

How to Mitigate CVE-2026-2045

Immediate Actions Required

• Update GIMP to a patched version that addresses CVE-2026-2045
• Avoid opening XWD files from untrusted or unknown sources until the patch is applied
• Consider temporarily disabling XWD file import functionality if not required
• Educate users about the risks of opening image files from untrusted sources

Patch Information

GIMP has released a security fix addressing this vulnerability. The patch implements proper bounds checking in the XWD file parsing routines to prevent out-of-bounds write conditions. The fix is available in the GNOME GIMP commit 68b27dfb1cbd9b3f22d7fa624dbab8647ee5f275.

Organizations should prioritize applying this patch, particularly on systems where GIMP is used to process files from external or untrusted sources.

Workarounds

• Block or quarantine XWD file attachments at email gateways until patching is complete
• Configure web content filters to block XWD file downloads from untrusted domains
• Use application sandboxing to limit the impact of potential exploitation
• Implement network segmentation to contain any potential compromise from user workstations

# Example: Restrict XWD file handling on Linux systems
# Add to /etc/gimp/2.0/gimprc or user configuration
# Disable XWD plugin loading (adjust path as needed)
sudo chmod 000 /usr/lib/gimp/2.0/plug-ins/file-xwd/file-xwd