CVE-2026-23044: PM: hibernate: Fix crash when freeing invalid crypto compressor

Severity: unknown
Exploited in the wild: not listed in CISA KEV
EPSS: 0.2% probability of exploitation in the next 30 days
Public exploit or detection template: none known
Published: 2026-02-04 · updated 2026-06-17

Description

In the Linux kernel, the following vulnerability has been resolved: PM: hibernate: Fix crash when freeing invalid crypto compressor When crypto_alloc_acomp() fails, it returns an ERR_PTR value, not NULL. The cleanup code in save_compressed_image() and load_compressed_image() unconditionally calls crypto_free_acomp() without checking for ERR_PTR, which causes crypto_acomp_tfm() to dereference an invalid pointer and crash the kernel. This can be triggered when the compression algorithm is unavailable (e.g., CONFIG_CRYPTO_LZO not enabled). Fix by adding IS_ERR_OR_NULL() checks before calling crypto_free_acomp() and acomp_request_free(), similar to the existing kthread_stop() check. [ rjw: Added 2 empty code lines ]

Affected products

Linux kernel: 6.15 — fixed in 6.19

How to fix

Upgrade to a fixed version: Linux kernel 6.19. Check the vendor advisory for mitigations.

References

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