CVE-2023-54239: In the Linux kernel, the following vulnerability has been resolved: iommufd: Check for uptr overflow syzkaller found that setting up a map with a user VA that

In the Linux kernel, the following vulnerability has been resolved: iommufd: Check for uptr overflow syzkaller found that setting up a map with a user VA that

In the Linux kernel, the following vulnerability has been resolved: iommufd: Check for uptr overflow syzkaller found that setting up a map with a user VA that wraps past zero can trigger WARN_ONs, particularly from pin_user_pages weirdly returning 0 due to invalid arguments. Prevent creating a pages with a uptr and size that would math overflow. WARNING: CPU: 0 PID: 518 at drivers/iommu/iommufd/pages.c:793 pfn_reader_user_pin+0x2e6/0x390 Modules linked in: CPU: 0 PID: 518 Comm: repro Not tainted 6.3.0-rc2-eeac8ede1755+ #1 Hardware name: QEMU Standard PC (i440FX + PIIX, 1996), BIOS rel-1.16.0-0-gd239552ce722-prebuilt.qemu.org 04/01/2014 RIP: 0010:pfn_reader_user_pin+0x2e6/0x390 Code: b1 11 e9 25 fe ff ff e8 28 e4 0f ff 31 ff 48 89 de e8 2e e6 0f ff 48 85 db 74 0a e8 14 e4 0f ff e9 4d ff ff ff e8 0a e4 0f ff <0f> 0b bb f2 ff ff ff e9 3c ff ff ff e8 f9 e3 0f ff ba 01 00 00 00 RSP: 0018:ffffc90000f9fa30 EFLAGS: 00010246 RAX: 0000000000000000 RBX: 0000000000000000 RCX: ffffffff821e2b72 RDX: 0000000000000000 RSI: ffff888014184680 RDI: 0000000000000002 RBP: ffffc90000f9fa78 R08: 00000000000000ff R09: 0000000079de6f4e R10: ffffc90000f9f790 R11: ffff888014185418 R1

Description from the National Vulnerability Database, published by 416baaa9-dc9f-4396-8d5f-8c081fb06d67

What it means for a small business

Linux is on the computers, phones or browsers your team uses every day. Turn on automatic updates and restart: most of these fixes only take effect after a restart.

How likely is an attack? The Exploit Prediction Scoring System, run by FIRST (the global association of security response teams), puts the odds of this one being exploited in the next 30 days at 0.18%, higher than 8% of CVEs. That’s low, but low isn’t zero, and the odds jump the day someone publishes an exploit. Scored November 5, 2026, updated daily.

Check your own setup

Website check: reads what your site runs from the outside (WordPress version, plugins it can see, old server software) and matches it against this database.
Server check: what your web server says about itself, and whether that version has known flaws.

Sources

Part of the Huttenlocher Technologies vulnerability database, refreshed twice a day from CISA and the NVD. The title, category and plain-language guidance are ours; check the linked record before acting on a detail. This is general guidance, not a review of your systems.

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