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CVE-2026-45908 Linux CVE debrief

A memory leak vulnerability exists in the Linux kernel's AMD XDNA accelerator driver. The `amdxdna_ubuf_map()` function in `accel/amdxdna` allocates memory for scatter-gather (sg) and internal sg table structures, but fails to free these allocations if subsequent operations—specifically `sg_alloc_table_from_pages()` or `dma_map_sgtable()`—fail. This results in a resource leak that could lead to memory exhaustion over time, particularly on systems with heavy accelerator workloads or frequent mapping failures. The vulnerability was resolved by ensuring proper cleanup paths are followed when these intermediate operations fail.

Vendor
Linux
Product
Unknown
CVSS
MEDIUM 5.5
CISA KEV
Not listed in stored evidence
Original CVE published
2026-05-27
Original CVE updated
2026-06-24
Advisory published
2026-05-27
Advisory updated
2026-06-24

Who should care

Organizations running Linux systems with AMD XDNA AI accelerators (such as Ryzen AI or Instinct MI series with XDNA support), kernel developers maintaining accelerator drivers, and security teams tracking kernel memory safety issues.

Technical summary

The vulnerability is located in `drivers/accel/amdxdna/amdxdna_gem.c` in the `amdxdna_ubuf_map()` function. The function allocates `struct sg_table *sgt` and internal sg structures via `sg_alloc_table()`, but the error handling paths for `sg_alloc_table_from_pages()` and `dma_map_sgtable()` failures do not call `sg_free_table()` or `kfree(sgt)`, resulting in a memory leak. The fix adds proper cleanup by calling `sg_free_table()` and freeing `sgt` before returning error codes in these failure paths. This is a classic resource leak bug where allocation and deallocation paths are mismatched in error handling code.

Defensive priority

medium

Recommended defensive actions

  • Apply kernel updates containing the fix commits once available through your distribution's security channel
  • Monitor for stable kernel releases backporting the fix to affected LTS branches
  • Review systems utilizing AMD XDNA accelerators for unusual memory consumption patterns
  • Consider enabling kernel memory leak detection (KMEMLEAK) on development/staging systems to catch similar issues
  • Track NVD entry for CVSS scoring once analysis is completed

Evidence notes

The CVE description and kernel commit references confirm the vulnerability is a memory leak in error handling paths within the AMD XDNA driver. The fix ensures allocated sg structures are properly freed when `sg_alloc_table_from_pages()` or `dma_map_sgtable()` return errors. No CVSS score or severity has been assigned by NVD as of the CVE publication date.

Sources and references

Verified primary and authoritative sources

  • CVE-2026-45908 CVE Program record

    Publisher, destination, and source semantics verified

    URL: https://www.cve.org/CVERecord?id=CVE-2026-45908

    CVE Program - Official CVE Program record with source-provided CVE metadata.

  • CVE-2026-45908 NVD vulnerability detail

    Publisher, destination, and source semantics verified

    URL: https://nvd.nist.gov/vuln/detail/CVE-2026-45908

    NIST National Vulnerability Database - Official NIST NVD detail page and source-specific vulnerability assessment.

Supplemental references

  • Source reference

    Unverified legacy reference

    URL: https://git.kernel.org/stable/c/5a68d2c99c859e6e8e36fa4e32749abf6d1fb66a

    416baaa9-dc9f-4396-8d5f-8c081fb06d67

  • Source reference

    Unverified legacy reference

    URL: https://git.kernel.org/stable/c/84dd57fb0359500092f1101409ca32091731490d

    416baaa9-dc9f-4396-8d5f-8c081fb06d67

  • Source reference

    Unverified legacy reference

    URL: https://git.kernel.org/stable/c/f9f4366d2ff93b07c2571561c776bd9a708078c3

    416baaa9-dc9f-4396-8d5f-8c081fb06d67

Methodology and review provenance

AI-assisted synthesis based on stored public vulnerability evidence. System validation, approval state, and publication status do not by themselves establish human review of this revision. PatchSiren helps prioritize defensive review and does not prove exposure or remediation on any system.