CVE-2026-97906 (GCVE-0-2026-97906)

Vulnerability from cvelistv5 – Published: 2026-09-25 10:22 – Updated: 2026-10-21 12:53
VLAI
Title
bootconfig: Fix integer overflow in initrd size check
Summary
In the Linux kernel, the following vulnerability has been resolved: bootconfig: Fix integer overflow in initrd size check Sashiko reported that in get_boot_config_from_initrd(), a crafted initrd with a huge bootconfig size (such as 0xFFFFFFFF) can cause the pointer arithmetic: data = ((void *)hdr) - size; to wrap around on 32-bit systems (or when pointer subtraction overflows). Because data wraps around, the subsequent bounds check: if ((unsigned long)data < initrd_start) evaluates to false, bypassing the check. The kernel then calls xbc_calc_checksum(data, size), which attempts to read 4GB of memory, hitting unmapped pages and triggering a fatal kernel page fault during early boot. Furthermore, on 64-bit systems with an initrd > 4.29 GB, an unbounded 32-bit size can similarly bypass the initrd_start check. Fix this by: 1. Ensuring the initrd is at least large enough to contain the bootconfig footer and verifying hdr is within the initrd bounds. 2. Checking that size does not exceed XBC_DATA_MAX and does not exceed the available space between initrd_start and hdr before performing pointer subtraction.
Severity
No CVSS data available.
Assigner
Linux CNA under the mitre root
CNA scorecard D 53/100 over 6642 records in the last 180 days details
References
Impacted products
Vendor Product Version CPE status
Linux Linux Affected: de462e5f10718517bacf2f84c8aa2804567ef7df , < 97be05f33f79342ea65d9b99c9ad07a93b8eef5a (git)
Affected: de462e5f10718517bacf2f84c8aa2804567ef7df , < 4d45bc0f8cdf606d5409b5f64a8a6609f6520c03 (git)
Affected: de462e5f10718517bacf2f84c8aa2804567ef7df , < 8d4343a411eaa182d323ab5b149496416015f27d (git)
Affected: de462e5f10718517bacf2f84c8aa2804567ef7df , < bff9a1579e2c9b2a59fdf3793becc9d7bf5ff1a6 (git)
Affected: de462e5f10718517bacf2f84c8aa2804567ef7df , < 7812d6dab0698001e50e8c2f901e17da3eb6f429 (git)
Affected: 32394df25d8e46935b442b429d74b37885c4f092 (git)
Affected: 5.6.14 , < 5.7 (semver)
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Linux Linux Affected: 5.7
Unaffected: 0 , < 5.7 (semver)
Unaffected: 6.6.160 , ≤ 6.6.* (semver)
Unaffected: 6.12.112 , ≤ 6.12.* (semver)
Unaffected: 6.18.53 , ≤ 6.18.* (semver)
Unaffected: 7.2.7 , ≤ 7.2.* (semver)
Unaffected: 7.3 , ≤ * (original_commit_for_fix)
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}



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