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no cvss —

CVE-2025-68194 json

media: imon: make send_packet() more robust

published 2025-12-16 10 mo ago modified 2026-10-14 26 d ago also EUVD-2025-203702

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 11%
public exploits
0
none known

Summary

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

media: imon: make send_packet() more robust

syzbot is reporting that imon has three problems which result in hung tasks due to forever holding device lock [1].

First problem is that when usb_rx_callback_intf0() once got -EPROTO error after ictx->dev_present_intf0 became true, usb_rx_callback_intf0() resubmits urb after printk(), and resubmitted urb causes usb_rx_callback_intf0() to again get -EPROTO error. This results in printk() flooding (RCU stalls).

Alan Stern commented [2] that

In theory it's okay to resubmit _if_ the driver has a robust error-recovery scheme (such as giving up after some fixed limit on the number of errors or after some fixed time has elapsed, perhaps with a time delay to prevent a flood of errors). Most drivers don't bother to do this; they simply give up right away. This makes them more vulnerable to short-term noise interference during USB transfers, but in reality such interference is quite rare. There's nothing really wrong with giving up right away.

but imon has a poor error-recovery scheme which just retries forever; this behavior should be fixed.

Since I'm not sure whether it is safe for imon users to give up upon any error code, this patch takes care of only union of error codes chosen from modules in drivers/media/rc/ directory which handle -EPROTO error (i.e. ir_toy, mceusb and igorplugusb).

Second problem is that when usb_rx_callback_intf0() once got -EPROTO error before ictx->dev_present_intf0 becomes true, usb_rx_callback_intf0() always resubmits urb due to commit 8791d63af0cf ("[media] imon: don't wedge hardware after early callbacks"). Move the ictx->dev_present_intf0 test introduced by commit 6f6b90c9231a ("[media] imon: don't parse scancodes until intf configured") to immediately before imon_incoming_packet(), or the first problem explained above happens without printk() flooding (i.e. hung task).

Third problem is that when usb_rx_callback_intf0() is not called for some reason (e.g. flaky hardware; the reproducer for this problem sometimes prevents usb_rx_callback_intf0() from being called), wait_for_completion_interruptible() in send_packet() never returns (i.e. hung task). As a workaround for such situation, change send_packet() to wait for completion with timeout of 10 seconds.

Patch / fix

  • Linux Linux 5.4.302, 5.10.247, 5.15.197, 6.1.159, 6.6.117, 6.12.58, 6.17.8, 6.18
  • linux Debian 12 6.1.159-1
  • linux Debian 13 6.12.63-1
  • linux Debian 14 6.17.8-1

debian advisories DEBIAN-CVE-2025-68194

  • linux Ubuntu 22.04 LTS 5.15.0-173.183
  • linux Ubuntu 24.04 LTS 6.8.0-106.106
  • linux Ubuntu 25.10 6.17.0-14.14
  • linux-aws Ubuntu 22.04 LTS 5.15.0-1103.110
  • linux-aws Ubuntu 24.04 LTS 6.8.0-1050.53
  • linux-aws Ubuntu 25.10 6.17.0-1007.7
  • linux-gcp Ubuntu 22.04 LTS 5.15.0-1103.112
  • linux-gcp Ubuntu 24.04 LTS 6.8.0-1052.55

ubuntu advisories UBUNTU-CVE-2025-68194

Ubuntu security data © Canonical Ltd., from https://github.com/canonical/ubuntu-security-notices via OSV; changed: normalised to fixed package versions per release. CC BY-SA 4.0

  • kernel-rt Linux Micro 6.1, Linux Micro 6.0 6.4.0-40.1
  • kernel-source-rt Linux Micro 6.1, Linux Micro 6.0 6.4.0-40.1
  • kernel-source Linux Micro 6.1, Linux Micro 6.0 6.4.0-39.1
  • kernel-default Linux Micro 6.1, Linux Micro 6.0 6.4.0-39.1
  • kernel-kvmsmall Linux Micro 6.1, Linux Micro 6.0 6.4.0-39.1
  • kernel-default-base Linux Micro 6.1, Linux Micro 6.0 6.4.0-39.1.21.16
  • kernel-rt Linux Micro 6.2 6.12.0-160000.9.1
  • kernel-64kb SLES 16.0, Linux Micro 6.2, SLES for SAP applications 16.0 6.12.0-160000.9.1

suse advisories SUSE-SU-2026:20845-1SUSE-SU-2026:20876-1SUSE-SU-2026:20477-1SUSE-SU-2026:20498-1SUSE-SU-2026:20207-1SUSE-SU-2026:20220-1

  • kernel-rt openSUSE Leap 16.0 6.12.0-160000.9.1
  • dtb-aarch64 openSUSE Leap 16.0 6.12.0-160000.9.1
  • kernel-64kb openSUSE Leap 16.0 6.12.0-160000.9.1
  • kernel-syms openSUSE Leap 16.0 6.12.0-160000.9.1
  • kernel-azure openSUSE Leap 16.0 6.12.0-160000.9.1
  • kernel-obs-qa openSUSE Leap 16.0 6.12.0-160000.9.1
  • kernel-source openSUSE Leap 16.0 6.12.0-160000.9.1
  • kernel-default openSUSE Leap 16.0 6.12.0-160000.9.1

opensuse advisories openSUSE-SU-2026:20145-1

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-2025-68194 updated cvss 5.5

kernel: Linux kernel: imon media driver denial of service via USB error handling

  • 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
    affected: no fix available “Fix deferred”
  • Red Hat Enterprise Linux 9 rv, perf, rtla, kernel, bpftool, libperf, +83 more Red Hat Enterprise Linux 10 kernel
    not affected: vulnerable code not present

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

0.21% chance of exploitation in the next 30 days, higher than 11% of all scored CVEs (FIRST EPSS, 2026-11-08).

Affected products

  • Linux Linux

Classification

Technology feeds

References

Sources

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