In the Linux kernel, the following vulnerability has been resolved:
drm/amdkfd: Fix watch_id bounds checking in debug address watch v2
The address watch clear code receives watch_id as an unsigned value
(u32), but some helper functions were using a signed int and checked
bits by shifting with watch_id.
If a very large watch_id is passed from userspace, it can be converted
to a negative value. This can cause invalid shifts and may access
memory outside the watch_points array.
drm/amdkfd: Fix watch_id bounds checking in debug address watch v2
Fix this by checking that watch_id is within MAX_WATCH_ADDRESSES before
using it. Also use BIT(watch_id) to test and clear bits safely.
This keeps the behavior unchanged for valid watch IDs and avoids
undefined behavior for invalid ones.
Fixes the below:
drivers/gpu/drm/amd/amdgpu/../amdkfd/kfd_debug.c:448
kfd_dbg_trap_clear_dev_address_watch() error: buffer overflow
'pdd->watch_points' 4 <= u32max user_rl='0-3,2147483648-u32max' uncapped
drivers/gpu/drm/amd/amdgpu/../amdkfd/kfd_debug.c
433 int kfd_dbg_trap_clear_dev_address_watch(struct kfd_process_device *pdd,
434 uint32_t watch_id)
435 {
436 int r;
437
438 if (!kfd_dbg_owns_dev_watch_id(pdd, watch_id))
kfd_dbg_owns_dev_watch_id() doesn't check for negative values so if
watch_id is larger than INT_MAX it leads to a buffer overflow.
(Negative shifts are undefined).
439 return -EINVAL;
440
441 if (!pdd->dev->kfd->shared_resources.enable_mes) {
442 r = debug_lock_and_unmap(pdd->dev->dqm);
443 if (r)
444 return r;
445 }
446
447 amdgpu_gfx_off_ctrl(pdd->dev->adev, false);
--> 448 pdd->watch_points[watch_id] = pdd->dev->kfd2kgd->clear_address_watch(
449 pdd->dev->adev,
450 watch_id);
v2: (as per, Jonathan Kim)
- Add early watch_id >= MAX_WATCH_ADDRESSES validation in the set path to
match the clear path.
- Drop the redundant bounds check in kfd_dbg_owns_dev_watch_id().
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: 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 (CISA Vulnrichment) · Automatable no (CISA Vulnrichment) · Technical impact total (CISA Vulnrichment). All three are CISA's SSVC values (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.
In CISA KEV no (CISA's KEV catalog) · Automatable no (CISA Vulnrichment) · Technical impact total (CISA Vulnrichment). 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