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Fencer Vulns
no cvss —

CVE-2026-98827 json

wifi: ath9k_htc: bound TX aggregation to MAX_TX_BUF_SIZE

published 2026-10-18 21 d ago modified 2026-10-19 20 d ago also EUVD-2026-103767

cvss
—
not scored
cisa kev
Not listed
not in CISA's catalog
epss
0.2%
EPSS 0.2% chance of exploitation in 30 days, percentile 9%
public exploits
0
none known

Summary

In the Linux kernel, the following vulnerability has been resolved:

wifi: ath9k_htc: bound TX aggregation to MAX_TX_BUF_SIZE

__hif_usb_tx() dequeues up to MAX_TX_AGGR_NUM (20) frames into a single tx_buf of MAX_TX_BUF_SIZE (32768) bytes, limiting the batch by record count but never by cumulative byte length.

With large frames (MTU 2304), 20 aggregated frames of 2292 bytes each exceed the allocation (20 * 2296 = 45920 bytes), so the memcpy() in the loop writes up to 13152 bytes past tx_buf->buf before usb_submit_urb().

Peek the queue head and stop before copying any record that would cross MAX_TX_BUF_SIZE, then dispatch the current batch. Leftover skbs remain queued and are drained on the next URB completion.

The byte bound changes the loop's exit semantics: it can now exit before i == tx_skb_cnt - 1. Stock only finalized tx_buf->len on that last index (len += offset), so an early break would submit a URB holding only the last record's length while every dequeued skb is freed on completion, silently dropping frames. Make tx_buf->len a running total and advance tx_buf->offset per record instead; the stride round_up(nskb->len + 4, 4) is identical to the stock stride when the loop runs to completion.

Tested on hardware with an MTU 2304 flood: the loop stops at record 15 (len = 32144, offset = 32144, within 32768), no oversized URB is submitted, and MTU 1500 pings pass 20/20.

Patch / fix

  • Linux Linux 6.12.113, 6.18.56, 7.2.10, 7.3
  • linux Debian 13 6.12.113-1
  • linux Debian 14 7.2.10-1
  • linux-6.12 Debian 12 6.12.113-1~deb12u1

debian advisories DEBIAN-CVE-2026-98827

Vendor advisories

What the vendors themselves say about their products: affected, fixed or not affected, and what to do.

red hat product security vex CVE-2026-98827 updated cvss 5.3

kernel: wifi: ath9k_htc: bound TX aggregation to MAX_TX_BUF_SIZE

  • Red Hat Enterprise Linux 6 perf, kernel, python-perf, kernel-kdump, kernel-firmware, kernel-bootwrapper, +1 more
    affected: no fix planned “Out of support scope”
  • Red Hat Enterprise Linux 7 perf, kernel, bpftool, kernel-rt, python-perf, kernel-kdump, +8 more Red Hat Enterprise Linux 8 perf, kernel, bpftool, kernel-rt, kernel-core, kernel-tools, +29 more Red Hat Enterprise Linux 9 rv, perf, rtla, kernel, bpftool, libperf, +83 more Red Hat Enterprise Linux 10 kernel Red Hat OpenShift Container Platform 4 openshift/ose-rhel-coreos-8, openshift/ose-rhel-coreos-9 Red Hat OpenShift Container Platform 5 openshift/ose-rhel-coreos-9
    affected: no fix available “Fix deferred”

Red Hat CSAF VEX © Red Hat, Inc., from https://security.access.redhat.com/data/csaf/v2/vex/; changed: reduced to product statuses and remediations. CC BY 4.0 · csaf

Exploit prediction

0.20% chance of exploitation in the next 30 days, higher than 9% of all scored CVEs (FIRST EPSS, 2026-11-08).

Affected products

  • Linux Linux

Classification

Technology feeds

References

Sources

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