{"answers":{"affected":"","exploited":"There is no known exploitation of CVE-2025-39993 in the wild and no public exploit code.","fix":"Apply the vendor's patch.","what":"CVE-2025-39993 is a high-severity use after free vulnerability in Linux, published on 15 Oct 2025. It can only be exploited from the same machine or local network, with no action from the victim."},"fix_prompt":"Check this codebase for CVE-2025-39993 and fix it if it is affected.\n\nWhat it is: CVE-2025-39993 is a high-severity use after free vulnerability in Linux, published on 15 Oct 2025. It can only be exploited from the same machine or local network, with no action from the victim.\nExploitation: There is no known exploitation of CVE-2025-39993 in the wild and no public exploit code.\n\nAffected product: Linux. No package-level version data is available, so check the vendor advisory linked from the reference page.\n\nTask:\n1. Search the dependency manifests and lockfiles (for example package.json, package-lock.json, requirements.txt, poetry.lock, uv.lock, pom.xml, build.gradle, go.mod, Cargo.lock, Gemfile.lock) and any Dockerfiles for the affected packages, including transitive dependencies.\n2. If an affected version is in use, upgrade it to the fixed version for its release line with the project's package manager, so the lockfile is regenerated. Prefer the smallest upgrade that fixes it.\n3. If there is no fix, or the upgrade would break the build, do not guess: explain the risk and the safest workaround instead.\n4. Run the tests and summarise what changed and why.\n5. If nothing in the project is affected, say so and change nothing.\n\nReference: https://insights.sbomify.com/CVE-2025-39993/ (Markdown: https://insights.sbomify.com/CVE-2025-39993/index.md)","id":"CVE-2025-39993","markdown":"https://insights.sbomify.com/CVE-2025-39993/index.md","name":"CVE-2025-39993","record":{"aliases":["BELL-CVE-2025-39993","DEBIAN-CVE-2025-39993","GHSA-2c3m-5h4x-9w2g","ROOT-OS-DEBIAN-11-CVE-2025-39993","ROOT-OS-DEBIAN-12-CVE-2025-39993","ROOT-OS-DEBIAN-13-CVE-2025-39993","ROOT-OS-UBUNTU-2204-CVE-2025-39993","ROOT-OS-UBUNTU-2404-CVE-2025-39993","UBUNTU-CVE-2025-39993"],"analysis":{"component_type":"kernel","fix_type":"patch","impacts":["code_execution","privilege_escalation"],"network_reachable":"adjacent_or_local","non_default_config":false,"product_category":"Linux kernel driver","requires_auth":"low_privilege","summary":"A race condition in the Linux kernel iMON driver allows a use-after-free, potentially enabling local attackers to execute code or escalate privileges.","user_interaction":"not_required","vuln_class":"use_after_free"},"analysis_generated_by":"qwen3.8-flash-next","assigner":"Linux","cpe":[],"cvss":{"score":7.8,"severity":"high","source":"cna","vector":"CVSS:3.1/AV:L/AC:L/PR:L/UI:N/S:U/C:H/I:H/A:H","version":"3.1"},"cwes":[],"description":"In the Linux kernel, the following vulnerability has been resolved:\n\nmedia: rc: fix races with imon_disconnect()\n\nSyzbot reports a KASAN issue as below:\nBUG: KASAN: use-after-free in __create_pipe include/linux/usb.h:1945 [inline]\nBUG: KASAN: use-after-free in send_packet+0xa2d/0xbc0 drivers/media/rc/imon.c:627\nRead of size 4 at addr ffff8880256fb000 by task syz-executor314/4465\n\nCPU: 2 PID: 4465 Comm: syz-executor314 Not tainted 6.0.0-rc1-syzkaller #0\nHardware name: QEMU Standard PC (Q35 + ICH9, 2009), BIOS 1.14.0-2 04/01/2014\nCall Trace:\n \u003cTASK\u003e\n__dump_stack lib/dump_stack.c:88 [inline]\ndump_stack_lvl+0xcd/0x134 lib/dump_stack.c:106\nprint_address_description mm/kasan/report.c:317 [inline]\nprint_report.cold+0x2ba/0x6e9 mm/kasan/report.c:433\nkasan_report+0xb1/0x1e0 mm/kasan/report.c:495\n__create_pipe include/linux/usb.h:1945 [inline]\nsend_packet+0xa2d/0xbc0 drivers/media/rc/imon.c:627\nvfd_write+0x2d9/0x550 drivers/media/rc/imon.c:991\nvfs_write+0x2d7/0xdd0 fs/read_write.c:576\nksys_write+0x127/0x250 fs/read_write.c:631\ndo_syscall_x64 arch/x86/entry/common.c:50 [inline]\ndo_syscall_64+0x35/0xb0 arch/x86/entry/common.c:80\nentry_SYSCALL_64_after_hwframe+0x63/0xcd\n\nThe iMON driver improperly releases the usb_device reference in\nimon_disconnect without coordinating with active users of the\ndevice.\n\nSpecifically, the fields usbdev_intf0 and usbdev_intf1 are not\nprotected by the users counter (ictx-\u003eusers). During probe,\nimon_init_intf0 or imon_init_intf1 increments the usb_device\nreference count depending on the interface. However, during\ndisconnect, usb_put_dev is called unconditionally, regardless of\nactual usage.\n\nAs a result, if vfd_write or other operations are still in\nprogress after disconnect, this can lead to a use-after-free of\nthe usb_device pointer.\n\nThread 1 vfd_write                      Thread 2 imon_disconnect\n                                        ...\n                                        if\n                                          usb_put_dev(ictx-\u003eusbdev_intf0)\n                                        else\n                                          usb_put_dev(ictx-\u003eusbdev_intf1)\n...\nwhile\n  send_packet\n    if\n      pipe = usb_sndintpipe(\n        ictx-\u003eusbdev_intf0) UAF\n    else\n      pipe = usb_sndctrlpipe(\n        ictx-\u003eusbdev_intf0, 0) UAF\n\nGuard access to usbdev_intf0 and usbdev_intf1 after disconnect by\nchecking ictx-\u003edisconnected in all writer paths. Add early return\nwith -ENODEV in send_packet(), vfd_write(), lcd_write() and\ndisplay_open() if the device is no longer present.\n\nSet and read ictx-\u003edisconnected under ictx-\u003elock to ensure memory\nsynchronization. Acquire the lock in imon_disconnect() before setting\nthe flag to synchronize with any ongoing operations.\n\nEnsure writers exit early and safely after disconnect before the USB\ncore proceeds with cleanup.\n\nFound by Linux Verification Center (linuxtesting.org) with Syzkaller.","ecosystems":[],"exploits":{"exploitdb":0,"first_seen":null,"github_poc":0,"max_poc_stars":null,"metasploit":0,"nuclei":0,"refs":[],"tier":"none_known"},"has_fix":true,"headline":"media: rc: fix races with imon_disconnect()","id":"CVE-2025-39993","indexable":true,"kev":null,"kind":"cve","links":{"ecosystem":null,"product":null,"products":[],"type":"use_after_free","year":"2025"},"n_packages":0,"n_references":9,"next":{"headline":"media: tuner: xc5000: Fix use-after-free in xc5000_release","id":"CVE-2025-39994"},"packages":[],"prev":{"headline":"mm: swap: check for stable address space before operating on the VMA","id":"CVE-2025-39992"},"products":["Linux"],"published":"2025-10-15","related":[],"sources":[{"class":"attribution","licence":"CVE Terms of Use (MITRE)","name":"CVE List","prefix":"CVE"},{"class":"attribution","licence":"FIRST CVSS licence","name":"CVSS (FIRST)"}],"ssvc":{"automatable":"no","exploitation":"none","technical_impact":"partial"},"state":"PUBLISHED","updated":"2026-08-05","vendors":["Linux"]},"summary":"A race condition in the Linux kernel iMON driver allows a use-after-free, potentially enabling local attackers to execute code or escalate privileges.","url":"https://insights.sbomify.com/CVE-2025-39993/"}