Kernel memory disclosure via incomplete fbcon rollback
Published Jul 19, 2026 · Updated Jul 19, 2026
Out-of-bounds read in Linux Kernel affected releases allows local users to disclose kernel memory through the framebuffer console. The fbcon_do_set_font() error path restores the prior font size but leaves vc_hi_font_mask and the screen buffer in their changed state after vc_resize() fails. Reaching the flaw requires permission to change a virtual-console font and an allocation failure; later rendering reads beyond the reverted font array, disclosing kernel data or crashing the system.
Summary
What happened
Out-of-bounds read in Linux Kernel affected releases allows local users to disclose kernel memory through the framebuffer console. The fbcon_do_set_font() error path restores the prior font size but leaves vc_hi_font_mask and the screen buffer in their changed state after vc_resize() fails. Reaching the flaw requires permission to change a virtual-console font and an allocation failure; later rendering reads beyond the reverted font array, disclosing kernel data or crashing the system.
The record
- CVE
- CVE-2026-53402
- Published
- Jul 19, 2026
- Updated
- Jul 19, 2026
- Vendor
- The Linux Kernel Organization
- Product
- Linux Kernel
- Classifications
- CWE-125
- Attack vector
- local
- Privileges
- authenticated
Timeline
How it unfolded
- Jul 19, 2026CVE publishedPublication date reported by the CVE source.
- Jul 19, 2026Record updatedLatest update available in the CVE record.
Exploitability
Present is not the same as exploitable
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Is a vulnerable build present?
Compare these published version ranges with your installed build and any vendor patches.
- Affected versionversion=5.10.249 <5.11
- Affected versionversion=5.15.64 <5.16
- Affected versionversion=5.19.6 <5.20
- Affected versionversion=6.0
- Affected versionversion=868749a7456dc48e93887a8474194e2ee6d6c21f
- Affected versionversion=a5a923038d70d2d4a86cb4e3f32625a5ee6e7e24 <076b1aa65f77a49bce5a48a4a55a397cfcafa2b8
- Affected versionversion=a5a923038d70d2d4a86cb4e3f32625a5ee6e7e24 <39815715cbcfabb16fc8c5f4a23deeda20f5df62
- Affected versionversion=a5a923038d70d2d4a86cb4e3f32625a5ee6e7e24 <8fdc8c2057eea08d40ce2c8eed41ff9e451c65c2
- Affected versionversion=a5a923038d70d2d4a86cb4e3f32625a5ee6e7e24 <b5bb2c696e140c399cb874def2feedf61dee27d6
- Affected versionversion=ebd6f886aa2447fcfcdce5450c9e1028e1d681bb
- Affected versionversion=f08ccb792d3eaf1dc62d8cbf6a30d6522329f660
What conditions does exploitation require?
What is affected?
Published CVSS scores
CVSS describes severity. EPSS estimates exploitation probability.
Attacks
What attackers are doing with it
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Weakness, pattern, technique
Public exploit references
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Technologies
Your stack
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Your stack
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