Bug 2532131 (CVE-2026-81012)

Summary: CVE-2026-81012 kernel: platform/x86: hp-bioscfg: fix off-by-one write in hp_get_string_from_buffer()
Product: [Other] Security Response Reporter: OSIDB Bzimport <bzimport>
Component: vulnerabilityAssignee: Product Security DevOps Team <prodsec-dev>
Status: NEW --- QA Contact:
Severity: medium Docs Contact:
Priority: medium    
Version: unspecifiedCC: akhatavk, aos-team-art-private, asdas, dpaolell, jdelft, jupierce, lgarciaa, mbiarnes, ppalepu, ppostler, prdhamdh, rhel-process-autobot, sghai, sidsharm, suppawar, vlaad, watson-tool-maintainers
Target Milestone: ---Keywords: Security
Target Release: ---   
Hardware: All   
OS: Linux   
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Doc Text:
A flaw was found in the Linux kernel's hp-bioscfg component. The `hp_get_string_from_buffer()` function contains an off-by-one write vulnerability. This occurs because the NUL terminator can be written one byte beyond the allocated buffer, leading to a buffer overflow. An attacker could potentially exploit this to cause memory corruption.
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oVirt Team: --- RHEL 7.3 requirements from Atomic Host:
Cloudforms Team: --- Target Upstream Version:
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Description OSIDB Bzimport 2026-09-11 20:48:46 UTC 
In the Linux kernel, the following vulnerability has been resolved:

platform/x86: hp-bioscfg: fix off-by-one write in hp_get_string_from_buffer()

hp_get_string_from_buffer() clamps the converted string length against
the destination buffer size with "size > dst_size", so when the
converted length is exactly equal to dst_size, conv_dst_size is left
at dst_size and the unconditional NUL terminator write

	dst[conv_dst_size] = 0;

lands one byte past the destination buffer. This is the same shape of
bug as the previously fixed off-by-one in hp_convert_hexstr_to_str():
the buffer is sized correctly for the content, but the terminator
write is never checked against that size.

Fix by changing the comparison to ">=" so conv_dst_size is always left
with room for the terminator.

All fixed-size destinations that reach this function (path[512],
current_value[512], current_password/current_value[64], and the
per-entry buffers in encodings[][512] and prerequisites[][512]) are
affected.
Comment 1 Keith Grant 2026-09-14 20:58:42 UTC 
Upstream advisory:
https://git.kernel.org/pub/scm/linux/security/vulns.git/plain/cve/published/2026/CVE-2026-81012.mbox