CVE ID : CVE-2025-40016<\/p>\n
Published : Oct. 20, 2025, 4:15 p.m. | 26\u00a0minutes ago<\/p>\n
Description : In the Linux kernel, the following vulnerability has been resolved:<\/p>\n
media: uvcvideo: Mark invalid entities with id UVC_INVALID_ENTITY_ID<\/p>\n
Per UVC 1.1+ specification 3.7.2, units and terminals must have a non-zero
\nunique ID.<\/p>\n
“`
\nEach Unit and Terminal within the video function is assigned a unique
\nidentification number, the Unit ID (UID) or Terminal ID (TID), contained in
\nthe bUnitID or bTerminalID field of the descriptor. The value 0x00 is
\nreserved for undefined ID,
\n“`<\/p>\n
If we add a new entity with id 0 or a duplicated ID, it will be marked
\nas UVC_INVALID_ENTITY_ID.<\/p>\n
In a previous attempt commit 3dd075fe8ebb (“media: uvcvideo: Require
\nentities to have a non-zero unique ID”), we ignored all the invalid units,
\nthis broke a lot of non-compatible cameras. Hopefully we are more lucky
\nthis time.<\/p>\n
This also prevents some syzkaller reproducers from triggering warnings due
\nto a chain of entities referring to themselves. In one particular case, an
\nOutput Unit is connected to an Input Unit, both with the same ID of 1. But
\nwhen looking up for the source ID of the Output Unit, that same entity is
\nfound instead of the input entity, which leads to such warnings.<\/p>\n
In another case, a backward chain was considered finished as the source ID
\nwas 0. Later on, that entity was found, but its pads were not valid.<\/p>\n
Here is a sample stack trace for one of those cases.<\/p>\n[ 20.650953] usb 1-1: new high-speed USB device number 2 using dummy_hcd
\n[ 20.830206] usb 1-1: Using ep0 maxpacket: 8
\n[ 20.833501] usb 1-1: config 0 descriptor??
\n[ 21.038518] usb 1-1: string descriptor 0 read error: -71
\n[ 21.038893] usb 1-1: Found UVC 0.00 device (2833:0201)
\n[ 21.039299] uvcvideo 1-1:0.0: Entity type for entity Output 1 was not initialized!
\n[ 21.041583] uvcvideo 1-1:0.0: Entity type for entity Input 1 was not initialized!
\n[ 21.042218] ————[ cut here ]————
\n[ 21.042536] WARNING: CPU: 0 PID: 9 at drivers\/media\/mc\/mc-entity.c:1147 media_create_pad_link+0x2c4\/0x2e0
\n[ 21.043195] Modules linked in:
\n[ 21.043535] CPU: 0 UID: 0 PID: 9 Comm: kworker\/0:1 Not tainted 6.11.0-rc7-00030-g3480e43aeccf #444
\n[ 21.044101] Hardware name: QEMU Standard PC (Q35 + ICH9, 2009), BIOS 1.15.0-1 04\/01\/2014
\n[ 21.044639] Workqueue: usb_hub_wq hub_event
\n[ 21.045100] RIP: 0010:media_create_pad_link+0x2c4\/0x2e0
\n[ 21.045508] Code: fe e8 20 01 00 00 b8 f4 ff ff ff 48 83 c4 30 5b 41 5c 41 5d 41 5e 41 5f 5d c3 cc cc cc cc 0f 0b eb e9 0f 0b eb 0a 0f 0b eb 06 0b eb 02 0f 0b b8 ea ff ff ff eb d4 66 2e 0f 1f 84 00 00 00 00
\n[ 21.046801] RSP: 0018:ffffc9000004b318 EFLAGS: 00010246
\n[ 21.047227] RAX: ffff888004e5d458 RBX: 0000000000000000 RCX: ffffffff818fccf1
\n[ 21.047719] RDX: 000000000000007b RSI: 0000000000000000 RDI: ffff888004313290
\n[ 21.048241] RBP: ffff888004313290 R08: 0001ffffffffffff R09: 0000000000000000
\n[ 21.048701] R10: 0000000000000013 R11: 0001888004313290 R12: 0000000000000003
\n[ 21.049138] R13: ffff888004313080 R14: ffff888004313080 R15: 0000000000000000
\n[ 21.049648] FS: 0000000000000000(0000) GS:ffff88803ec00000(0000) knlGS:0000000000000000
\n[ 21.050271] CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033
\n[ 21.050688] CR2: 0000592cc27635b0 CR3: 000000000431c000 CR4: 0000000000750ef0
\n[ 21.051136] PKRU: 55555554
\n[ 21.051331] Call Trace:
\n[ 21.051480]\n[ 21.051611] ? __warn+0xc4\/0x210
\n[ 21.051861] ? media_create_pad_link+0x2c4\/0x2e0
\n[ 21.052252] ? report_bug+0x11b\/0x1a0
\n[ 21.052540] ? trace_hardirqs_on+0x31\/0x40
\n[ 21.052901] ? handle_bug+0x3d\/0x70
\n[ 21.053197] ? exc_invalid_op+0x1a\/0x50
\n[ 21.053511] ? asm_exc_invalid_op+0x1a\/0x20
\n[ 21.053924] ? media_create_pad_link+0x91\/0x2e0
\n[ 21.054364] ? media_create_pad_link+0x2c4\/0x2e0
\n[ 21.054834] ? media_create_pad_link+0x91\/0x2e0
\n[ 21.055131] ? _raw_spin_unlock+0x1e\/0x40
\n[ 21.055441] ? __v4l2_device_register_subdev+0x202\/0x210
\n[ 21.055837] uvc_mc_register_entities+0x358\/0x400
\n[ 21.056144] uvc_register_chains+0x1
\n—truncated—<\/p>\n
Severity: 0.0 | NA<\/p>\n
Visit the link for more details, such as CVSS details, affected products, timeline, and more…\u00a0<\/p>\n","protected":false},"excerpt":{"rendered":"
CVE ID : CVE-2025-40016 Published : Oct. 20, 2025, 4:15 p.m. | 26\u00a0minutes ago Description : In the Linux kernel, the following vulnerability has been resolved: media: uvcvideo: Mark invalid entities with id UVC_INVALID_ENTITY_ID Per UVC 1.1+ specification 3.7.2, units and terminals must have a non-zero unique ID. “` Each Unit and Terminal within the …<\/p>\n","protected":false},"author":1,"featured_media":0,"comment_status":"closed","ping_status":"closed","sticky":false,"template":"","format":"standard","meta":{"footnotes":""},"categories":[26],"tags":[],"class_list":["post-71996","post","type-post","status-publish","format-standard","hentry","category-vulnerability"],"_links":{"self":[{"href":"https:\/\/afaghhosting.net\/blog\/wp-json\/wp\/v2\/posts\/71996","targetHints":{"allow":["GET"]}}],"collection":[{"href":"https:\/\/afaghhosting.net\/blog\/wp-json\/wp\/v2\/posts"}],"about":[{"href":"https:\/\/afaghhosting.net\/blog\/wp-json\/wp\/v2\/types\/post"}],"author":[{"embeddable":true,"href":"https:\/\/afaghhosting.net\/blog\/wp-json\/wp\/v2\/users\/1"}],"replies":[{"embeddable":true,"href":"https:\/\/afaghhosting.net\/blog\/wp-json\/wp\/v2\/comments?post=71996"}],"version-history":[{"count":0,"href":"https:\/\/afaghhosting.net\/blog\/wp-json\/wp\/v2\/posts\/71996\/revisions"}],"wp:attachment":[{"href":"https:\/\/afaghhosting.net\/blog\/wp-json\/wp\/v2\/media?parent=71996"}],"wp:term":[{"taxonomy":"category","embeddable":true,"href":"https:\/\/afaghhosting.net\/blog\/wp-json\/wp\/v2\/categories?post=71996"},{"taxonomy":"post_tag","embeddable":true,"href":"https:\/\/afaghhosting.net\/blog\/wp-json\/wp\/v2\/tags?post=71996"}],"curies":[{"name":"wp","href":"https:\/\/api.w.org\/{rel}","templated":true}]}}