Bug 2548385 (CVE-2026-98375)

Summary: CVE-2026-98375 kernel: xen/netfront: drop RX packets with a short Ethernet header
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 Xen network frontend driver. This vulnerability allows a malicious host backend to cause a Denial of Service (DoS) by transmitting incoming network packets with an incomplete Ethernet header. Because the driver fails to verify that incoming packet buffers meet the minimum required header size, processing malformed packets triggers a kernel crash or an out-of-bounds memory read.
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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 2026-10-09 07:41:31 UTC 
In the Linux kernel, the following vulnerability has been resolved:

xen/netfront: drop RX packets with a short Ethernet header

handle_incoming_queue() pulls pull_to bytes into the head before
calling eth_type_trans().  pull_to is the length of the first RX slot,
capped at RX_COPY_THRESHOLD, and that length comes from the backend.
Nothing checks it against ETH_HLEN.

If the first slot is shorter than ETH_HLEN and more slots follow, the
head ends up shorter than an Ethernet header while skb->len is longer,
and eth_type_trans() BUG()s in __skb_pull().  If the whole packet is
shorter than ETH_HLEN, eth_type_trans() reads the header past the end
of the data instead.

Pull at least ETH_HLEN, and drop the packet if that fails, which also
drops packets too short to hold an Ethernet header.  This also checks
the return value of the pull, which was ignored.
Comment 1 gkamathe 2026-10-10 14:55:09 UTC 
Upstream advisory:
https://git.kernel.org/pub/scm/linux/security/vulns.git/plain/cve/published/2026/CVE-2026-98375.mbox