Bug 2516972 (CVE-2026-74452)

Summary: CVE-2026-74452 kernel: drm/panthor: reject firmware sections with oversized data
Product: [Other] Security Response Reporter: OSIDB Bzimport <bzimport>
Component: vulnerabilityAssignee: Product Security DevOps Team <prodsec-dev>
Status: NEW --- QA Contact:
Severity: medium Docs Contact:
Priority: medium    
Version: unspecifiedCC: rhel-process-autobot, watson-tool-maintainers
Target Milestone: ---Keywords: Security
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Hardware: All   
OS: Linux   
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A flaw was found in the Linux kernel's drm/panthor component. This vulnerability allows a local attacker, by providing a specially crafted firmware, to cause a heap buffer overflow. This occurs because the data size to copy is not validated against the allocated section size, potentially leading to a massive out-of-bounds write in kernel memory. The most significant consequence is a denial of service, but it could potentially lead to further system compromise.
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oVirt Team: --- RHEL 7.3 requirements from Atomic Host:
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Description OSIDB Bzimport 2026-08-15 12:42:00 UTC
In the Linux kernel, the following vulnerability has been resolved:

drm/panthor: reject firmware sections with oversized data

In panthor_fw_load_section_entry(), the data size to copy is calculated
without validating it against the allocated section_size:

    section->data.size = hdr.data.end - hdr.data.start;

If a crafted firmware sets data.size larger than the allocated memory,
this could cause a heap buffer overflow in panthor_fw_init_section_mem()

    memcpy(section->mem->kmap, section->data.buf, section->data.size);

Additionally, if the section->data.size exceeds the BO size, could this
memset underflow the size calculation, leading to a massive out-of-bounds
zeroing of kernel memory?

    memset(section->mem->kmap + section->data.size, 0,
           panthor_kernel_bo_size(section->mem) - section->data.size);

Reject section entries whose initial data is larger than the section size.