CVE-2025-22023 usb: xhci: Don't skip on Stopped - Length Invalid

What is CVE-2025-22023?

CVE-2025-22023 is a high-severity use after free vulnerability in Linux kernel, published on 16 Apr 2025. It can only be exploited from the same machine or local network, with no action from the victim.

Official description

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

usb: xhci: Don't skip on Stopped - Length Invalid

Up until commit d56b0b2ab142 ("usb: xhci: ensure skipped isoc TDs are returned when isoc ring is stopped") in v6.11, the driver didn't skip missed isochronous TDs when handling Stoppend and Stopped - Length Invalid events. Instead, it erroneously cleared the skip flag, which would cause the ring to get stuck, as future events won't match the missed TD which is never removed from the queue until it's cancelled.

This buggy logic seems to have been in place substantially unchanged since the 3.x series over 10 years ago, which probably speaks first and foremost about relative rarity of this case in normal usage, but by the spec I see no reason why it shouldn't be possible.

After d56b0b2ab142, TDs are immediately skipped when handling those Stopped events. This poses a potential problem in case of Stopped - Length Invalid, which occurs either on completed TDs (likely already given back) or Link and No-Op TRBs. Such event won't be recognized as matching any TD (unless it's the rare Link TRB inside a TD) and will result in skipping all pending TDs, giving them back possibly before they are done, risking isoc data loss and maybe UAF by HW.

As a compromise, don't skip and don't clear the skip flag on this kind of event. Then the next event will skip missed TDs. A downside of not handling Stopped - Length Invalid on a Link inside a TD is that if the TD is cancelled, its actual length will not be updated to account for TRBs (silently) completed before the TD was stopped.

I had no luck producing this sequence of completion events so there is no compelling demonstration of any resulting disaster. It may be a very rare, obscure condition. The sole motivation for this patch is that if such unlikely event does occur, I'd rather risk reporting a cancelled partially done isoc frame as empty than gamble with UAF.

This will be fixed more properly by looking at Stopped event's TRB pointer when making skipping decisions, but such rework is unlikely to be backported to v6.12, which will stay around for a few years.

Weakness: CWE-416

Which versions are affected by CVE-2025-22023?

It affects 1 product.

Products include Linux kernel.

How do I fix CVE-2025-22023?

Apply the vendor's patch.

Upgrade to the fixed version. These bugs are found with fuzzing and sanitisers and avoided by memory-safe languages. More about Use after free.

Is CVE-2025-22023 being exploited?

There is no known exploitation of CVE-2025-22023 in the wild and no public exploit code.

Other vulnerabilities in Linux kernel

• CVE-2026-53266 Linux Kernel Out-of-Bounds Write Exploited High 8.8
• CVE-2013-6282 Linux Kernel Improper Input Validation Exploited High 8.8
• CVE-2022-0185 Linux Kernel Heap-Based Buffer Overflow Exploited High 8.4
• CVE-2013-2094 Linux Kernel Privilege Escalation Exploited High 8.4
• CVE-2026-53362 Linux Kernel Unspecified Exploited High 7.8

All Linux kernel vulnerabilities

Sources

• CVE record
• NVD
• OSV
• GitHub advisory
• How this page is made

Also known as BELL-CVE-2025-22023, DEBIAN-CVE-2025-22023, GHSA-wc2r-g885-938p, UBUNTU-CVE-2025-22023.