CVE-2026-89717

Description

In the Linux kernel, the following vulnerability has been resolved: zram: set default primary compressor in zram_destroy_comps() Patch series "zram: fix zram issues reported by sashiko". Sashiko drove by and reported [1] a couple of zram issues: a possible BUG_ON() in zlib code due to missing winbits range validation and one possible NULL-ptr dereference in zcomp. Both are low risk yet still worth fixing. This patch (of 2): zram_destroy_comps() resets all compressors and leaves them set to NULL, including the primary one, which is invalid device state, as now comp_algorithm_show()->strcmp() can be called on a NULL compressor. Set default primary compressor in zram_destroy_comps().

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EPSS — Exploit Prediction

0.0017

Probability of exploitation

0.06%

Percentile rank

EPSS estimates the probability that this vulnerability will be exploited in the wild within the next 30 days. A higher score means more likely to be exploited.

References

Other References

https://git.kernel.org/stable/c/5cec3e60e9f2d1324179df3aa91656f90095cf8f https://git.kernel.org/stable/c/dde75313eed0b014c437f48dd75c0308b592cbf9 https://git.kernel.org/stable/c/dea8f13c3dfad8b990f8ea96c997aabeebbc1d22

Frequently Asked Questions

What is CVE-2026-89717? +

In the Linux kernel, the following vulnerability has been resolved: zram: set default primary compressor in zram_destroy_comps() Patch series "zram: fix zram issues reported by sashiko". Sashiko drove by and reported [1] a couple of zram issues: a possible BUG_ON() in zlib code due to missing winbits range validation and one possible NULL-ptr dereference in zcomp. Both are low risk yet still worth fixing. This patch (of 2): zram_destroy_comps() resets all compressors and leaves them set to NULL, including the primary one, which is invalid device state, as now comp_algorithm_show()->strcmp() can be called on a NULL compressor. Set default primary compressor in zram_destroy_comps().

How do I check if I'm vulnerable to CVE-2026-89717? +

You can use Secably's free Website Scanner to check your website for known vulnerabilities. For infrastructure scanning, use the Port Scanner to identify exposed services that may be affected. Check the vendor advisories linked above for specific patch and version information.