Bug 2554982 (CVE-2026-98576)

Summary: CVE-2026-98576 kernel: nfc: llcp: fix slab-out-of-bounds reads when logging service names
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 Near Field Communication (NFC) subsystem. When processing certain service names and requests, the kernel attempts to log strings that lack null-termination using an unbounded format specifier. A local user can exploit this vulnerability to trigger an out-of-bounds memory read, potentially leading to a system crash and denial of service (DoS) or information disclosure.
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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 2026-10-18 15:37:19 UTC 
In the Linux kernel, the following vulnerability has been resolved:

nfc: llcp: fix slab-out-of-bounds reads when logging service names

nfc_llcp_wks_sap() and nfc_llcp_build_sdreq_tlv() pass non-null-
terminated strings to pr_debug() using the %s format specifier.
The buffers are allocated via kmemdup() or come from netlink
attributes and are not guaranteed to be null-terminated, causing
__dynamic_pr_debug() to read beyond the allocated region:

  KASAN: slab-out-of-bounds Read in __dynamic_pr_debug

Fix both call sites by using %.*s with the explicit length to limit
the output to the actual length of the string.