In the Linux kernel, the following vulnerability has been resolved:
media: cx231xx: reject geometry changes while the VBI queue is busy
vidioc_s_fmt_vid_cap() and vidioc_s_std() change the device-wide
dev->width / dev->norm but only refuse the change when the *video* queue
(dev->vidq) is busy. The VBI queue (dev->vbiq) shares that same geometry:
cx231xx_init_vbi_isoc() latches dma_q->lines_per_field from dev->norm,
the VBI videobuf2 plane is sized from dev->width / dev->norm in
vbi_queue_setup() and vbi_buf_prepare(), and cx231xx_do_vbi_copy() then
recomputes the destination offset from the *live* dev->width and the
latched lines_per_field on every URB completion:
offset = lines_completed * (dev->width << 1) + ...;
if (dma_q->current_field == 2)
offset += dev->width * 2 * dma_q->lines_per_field;
memcpy(plane + offset, p_buffer, lencopy);
Because the VBI node shares video_ioctl_ops with the video node, an
application can size a small VBI plane (REQBUFS/QBUF with a small width,
or with the NTSC standard), then enlarge dev->width (or switch dev->norm
to PAL) through the video node while the VBI stream is running -- the
change is allowed because only dev->vidq is checked -- and let the device
deliver a field-2 VBI payload. cx231xx_do_vbi_copy() now computes the
offset with the larger geometry and memcpy()s past the end of the smaller
plane that was already allocated, a heap out-of-bounds write whose offset
is attacker-chosen and whose contents come from the device. The
per-field guard in cx231xx_copy_vbi_line() does not help: it bounds the
copy against the latched lines_per_field, not the plane's real capacity,
and vb2 does not re-run buf_prepare() for an already prepared buffer.
Refuse the format/standard change when the VBI queue is busy as well, so
the geometry cannot change underneath an allocated VBI buffer.
What the EG score is made of (scorer v4.0: the three questions the 0–10 score mixes, published apart · methodology)
The EG score (7.8): severity, escalated by confirmed exploitation. This CVE's 7.8 is its impact severity (EG Severity), not escalated.
- EG Severity
- 7.8 HIGHCVSS-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 2026-10-27). 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