Bug 2555025 (CVE-2026-98612)

Summary: CVE-2026-98612 kernel: net: usb: catc: bound the RX packet length in catc_rx_done()
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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Fixed In Version: Doc Type: ---
Doc Text:
A flaw was found in the Linux kernel's CATC USB Ethernet driver. The driver fails to properly validate packet length boundaries when processing incoming multi-packet network transfers. An attacker could exploit this flaw by providing crafted packet headers, causing the driver to read beyond the allocated buffer or read uninitialized memory. This vulnerability primarily results in a system crash, leading to a Denial of Service (DoS), and may potentially expose sensitive system memory.
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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 15:39:59 UTC 
In the Linux kernel, the following vulnerability has been resolved:

net: usb: catc: bound the RX packet length in catc_rx_done()

catc_rx_done() walks a multi-packet URB, reading a two-byte length from
each packet header. Its bound, pkt_len > urb->actual_length, ignores the
header offset and compares against the whole transfer rather than the
bytes left from pkt_start, so a crafted packet header makes
skb_copy_to_linear_data() read past the buffer.

A length below ETH_HLEN is also accepted, including zero, and
eth_type_trans() then reads a MAC header from the uninitialised tailroom
of a shorter skb. The is_f5u011 branch takes its length straight from
the transfer, so a zero-length URB reaches the same path.

Track the bytes remaining from the current packet, and reject a header
that does not fit, a length past what is left, and a length below an
Ethernet header.

A transfer shorter than an Ethernet header, including a zero-length one,
previously became a runt skb passed to netif_rx() and counted as
received; it is now counted in rx_length_errors and ends the walk.