In the Linux kernel, the following vulnerability has been resolved:
media: vidtv: Fix a null-ptr-deref in vidtv_mux_stop_thread
syzbot report a null-ptr-deref in vidtv_mux_stop_thread. [1]
If dvb->mux is not initialized successfully by vidtv_mux_init() in the
vidtv_start_streaming(), it will trigger null pointer dereference about mux
in vidtv_mux_stop_thread().
Adjust the timing of streaming initialization and check it before
stopping it.
[1]
KASAN: null-ptr-deref in range [0x0000000000000128-0x000000000000012f]
CPU: 0 UID: 0 PID: 5842 Comm: syz-executor248 Not tainted 6.13.0-rc4-syzkaller-00012-g9b2ffa6148b1 #0
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 09/13/2024
RIP: 0010:vidtv_mux_stop_thread+0x26/0x80 drivers/media/test-drivers/vidtv/vidtv_mux.c:471
Code: 90 90 90 90 66 0f 1f 00 55 53 48 89 fb e8 82 2e c8 f9 48 8d bb 28 01 00 00 48 b8 00 00 00 00 00 fc ff df 48 89 fa 48 c1 ea 03 <0f> b6 04 02 84 c0 74 02 7e 3b 0f b6 ab 28 01 00 00 31 ff 89 ee e8
RSP: 0018:ffffc90003f2faa8 EFLAGS: 00010202
RAX: dffffc0000000000 RBX: 0000000000000000 RCX: ffffffff87cfb125
RDX: 0000000000000025 RSI: ffffffff87d120ce RDI: 0000000000000128
RBP: ffff888029b8d220 R08: 0000000000000005 R09: 0000000000000000
R10: 0000000000000000 R11: 0000000000000003 R12: ffff888029b8d188
R13: ffffffff8f590aa0 R14: ffffc9000581c5c8 R15: ffff888029a17710
FS: 00007f7eef5156c0(0000) GS:ffff8880b8600000(0000) knlGS:0000000000000000
CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033
CR2: 00007f7eef5e635c CR3: 0000000076ca6000 CR4: 00000000003526f0
DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000
DR3: 0000000000000000 DR6: 00000000fffe0ff0 DR7: 0000000000000400
Call Trace:
vidtv_stop_streaming drivers/media/test-drivers/vidtv/vidtv_bridge.c:209 [inline]
vidtv_stop_feed+0x151/0x250 drivers/media/test-drivers/vidtv/vidtv_bridge.c:252
dmx_section_feed_stop_filtering+0x90/0x160 drivers/media/dvb-core/dvb_demux.c:1000
dvb_dmxdev_feed_stop.isra.0+0x1ee/0x270 drivers/media/dvb-core/dmxdev.c:486
dvb_dmxdev_filter_stop+0x22a/0x3a0 drivers/media/dvb-core/dmxdev.c:559
dvb_dmxdev_filter_free drivers/media/dvb-core/dmxdev.c:840 [inline]
dvb_demux_release+0x92/0x550 drivers/media/dvb-core/dmxdev.c:1246
__fput+0x3f8/0xb60 fs/file_table.c:450
task_work_run+0x14e/0x250 kernel/task_work.c:239
get_signal+0x1d3/0x2610 kernel/signal.c:2790
arch_do_signal_or_restart+0x90/0x7e0 arch/x86/kernel/signal.c:337
exit_to_user_mode_loop kernel/entry/common.c:111 [inline]
exit_to_user_mode_prepare include/linux/entry-common.h:329 [inline]
__syscall_exit_to_user_mode_work kernel/entry/common.c:207 [inline]
syscall_exit_to_user_mode+0x150/0x2a0 kernel/entry/common.c:218
do_syscall_64+0xda/0x250 arch/x86/entry/common.c:89
entry_SYSCALL_64_after_hwframe+0x77/0x7f
What the EG score is made of (scorer v4.0: the three questions the 0–10 score mixes, published apart · methodology)
The EG score (5.5): severity, escalated by confirmed exploitation. This CVE's 5.5 is its impact severity (EG Severity), not escalated.
- EG Severity
- 5.5 MEDIUMCVSS-B, impact only: no KEV listing, EPSS or EG-KEV tier raises it.GitHub Security Advisory CVSS
- EG Likelihood
- 0.2% within 30 daysSource: FIRST EPSS (model v2026.06.15, score date 2026-10-25). FIRST's exploitation probability, not an EchelonGraph model.
- Confirmed exploitation
- None on record (CISA KEV, EG-KEV Tier 1)Reported apart from the likelihood: an observed fact, not a probability.
- EG Priority
- SSVC Track at medium mission impactTrack at low or medium mission impact; Track* at high (mission-essential systems).CISA BOD 26-04: 14 days if the affected system is publicly exposed; Fix on system upgrade if it is not.Each input and its source, and whom BOD 26-04 binds: the SSVC and BOD 26-04 blocks below.
SSVC (CISA's decision table, applied by EchelonGraph)Track at low or medium mission impact; Track* at high (mission-essential systems).
A fix is available. Apply it within your standard update timelines.
Exploitation none (no CISA value, KEV listing or exploit code on record) · Automatable no (CISA's BOD 26-04 default) · Technical impact total (CISA's BOD 26-04 default). EchelonGraph holds no SSVC assessment of this CVE from CISA: none of these inputs is from Vulnrichment. EchelonGraph applied CISA's decision table to them; CISA publishes SSVC inputs and the table, not a decision for each CVE. Mission impact is CISA's Mission & Well-being decision point, and only you can judge it. CISA's table makes it high when Mission Prevalence is Essential — the vulnerable component "directly provides capabilities that constitute at least one MEF for at least one entity" (MEF: mission essential function) — or when Public Well-Being Impact is Irreversible: "multiple fatalities are likely", the cyber-physical system "is likely lost or destroyed", "extreme or serious externalities" are imposed on other parties, or social systems such as elections or the financial grid "are destabilized and potentially collapse". CISA's decision table
BOD 26-04 (CISA's remediation timeline, Table 1)14 days if the affected system is publicly exposed; Fix on system upgrade if it is not.
The score's inputs: In CISA KEV no (CISA's KEV catalog) · Automatable no (CISA's BOD 26-04 default) · Technical impact total (CISA's BOD 26-04 default). Where an input reads “CISA's BOD 26-04 default”, no one has published it for this CVE, and CISA's implementation guidance says: “If “Automatable” and “Technical Impact” information items about a CVE ID are not available and the CVE ID is not in the KEV Catalog, CISA will treat its values as “no” and “total,” respectively, until CISA or a third party provides metadata about the CVE ID. CISA will always provide the Vulnrichment data for a CVE ID listed in the KEV Catalog.” Whether your system is publicly exposed is yours to answer. BOD 26-04 binds US Federal Civilian Executive Branch agencies; for anyone else it is CISA's published timeline, a reference rather than an obligation. The directive · how EchelonGraph applies it