CVE-2026-2049: GIMP HDR Heap Buffer Overflow Remote Code Execution

Technical summary

CVE-2026-2049 is a heap-based buffer overflow in GIMP's HDR file parsing logic. The vulnerability stems from insufficient validation of user-supplied data length before copying to a heap buffer, corresponding to CWE-122 (Heap-based Buffer Overflow) and CWE-131 (Incorrect Calculation of Buffer Size). The parsing code fails to enforce bounds checking, allowing an attacker to craft a malicious HDR file that, when processed by GIMP, corrupts heap memory and achieves code execution in the context of the GIMP process.

Business impact

Organizations relying on GIMP for image editing, batch processing, or graphic design workflows face potential compromise if users open untrusted HDR files. In mixed-OS environments where GIMP is deployed on Linux or macOS workstations, successful exploitation could grant attackers a foothold for lateral movement, data exfiltration, or persistence. The requirement for user interaction limits mass-exploitation risk but increases social engineering attack surface, particularly if HDR files are commonly shared in design or photography teams.

Affected systems

GIMP installations vulnerable to this vulnerability are affected across all supported platforms. The vendor and product information should be verified against the official GIMP security advisory to determine exact version ranges and patch availability. Users running current or older stable releases of GIMP should check the project's release notes and security announcements for patched versions.

Exploitability

Exploitability requires user interaction—the target must open a malicious HDR file or visit a malicious webpage serving one. The attack vector is local (file-based) with low complexity and no privileges required. While this lowers the exploitability score compared to a network-accessible flaw, it remains practical for targeted attacks, spear-phishing campaigns, or drive-by downloads. The HDR file format is legitimate and common in professional workflows, making social engineering plausible.

Remediation

Update GIMP to a patched version addressing CVE-2026-2049. Verify the specific patch version in the official GIMP security advisory or release notes. Interim mitigations include restricting HDR file handling to trusted sources, disabling automatic file opening in email clients, and educating users not to open HDR files from untrusted senders. Consider disabling HDR support in GIMP if not essential to your workflow.

Patch guidance

Consult the official GIMP project security advisories and release notes for patched version numbers. Patches are typically available through the project's download page and package managers (apt, brew, yum, etc.). Test patches in a non-production environment before deployment, especially in automated image processing pipelines. Verify that after patching, HDR parsing no longer triggers the vulnerability using the vendor's provided test cases or your own controlled HDR samples.

Detection guidance

Monitor for failed GIMP process executions, unusual child process spawning from GIMP, or segmentation faults in GIMP logs. File integrity monitoring can alert on unexpected modifications to GIMP binaries. Network-level detection of HDR file transfers to suspicious destinations may indicate lateral movement post-exploitation. Endpoint Detection and Response (EDR) solutions should flag heap corruption or code injection attempts targeting GIMP. Where possible, log all HDR file opens and track their provenance.

Why prioritize this

Although not yet listed on the CISA KEV catalog, this vulnerability merits HIGH priority due to its severity (CVSS 7.8), the direct path to code execution, and the likelihood of social engineering exploitation in design-heavy organizations. The lack of authentication requirements and relatively straightforward attack vector (opening a file) mean it could be weaponized quickly. Prioritize patching in environments where GIMP users handle files from external sources or untrusted networks.

Risk score, explained

CVE-2026-2049 scores 7.8 (HIGH) under CVSS 3.1 due to high impact across confidentiality, integrity, and availability (C:H, I:H, A:H), combined with a low attack complexity and no privilege requirement. The user interaction requirement (UI:R) prevents a critical rating but does not significantly diminish risk in real-world scenarios where HDR sharing is common. The local attack vector reflects the file-based nature of exploitation, typical of document-format vulnerabilities.

Frequently asked questions