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CVE-2026-98523

Microsoft — drm/client: fix restore of partially initialized client

Microsoft · Not classified by connected sources

Patch Tuesday
0

EVRS 0 of 100 Informational

Monitor

Rank 2,828 of 2,960 tracked

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Why it scores 0

Evidence available: 2 of 8 signals

No strong exploitation, disclosure, or severity signal is available for this CVE yet.

  • CISA KEVDid not apply
  • RansomwareNo data
  • Vendor exploitationNo data
  • EPSSDid not apply
  • Microsoft Exploitability IndexNo data
  • Pre-patch disclosureNo data
  • KEV recencyNo data
  • CVSSNo data

The band answers “how soon”, not “how bad”. No data for: Ransomware, Vendor exploitation, Microsoft Exploitability Index, Pre-patch disclosure, KEV recency, CVSS. Why some signals show no data

Fix

No fixed version identified yet

Affected versions

Not identified by the connected sources

Remediation

NVD lists one or more references for this CVE that aren't tagged as a patch or vendor advisory. Review them directly to confirm patch availability and applicability before making a remediation decision.

Evidence

Each value with its source
MeasureValueSource
CVSS base scoreHow severe the flaw is in itself. It does not say how likely an attack is. Not publishedNVD and the CVE record were checked and hold no score. NVD
FIRST EPSSFIRST's estimate of the chance this is exploited in the next 30 days, and how that ranks against all CVEs. 0.002 (10.4th pctl) FIRST EPSS
Actively exploitedWhether a source of record has confirmed attacks using it in the wild. Not confirmed Patch Tuesday
Public exploit moduleA module existing is not the same as active exploitation. None known Metasploit
EUVD cross-referenceENISA's record: CVSS 0.0, assigned by Linux. Listed ENISA EUVD

Description

NVD

In the Linux kernel, the following vulnerability has been resolved: drm/client: fix restore of partially initialized client I got a null-ptr-deref report when closing a DRM file descriptor: WARNING: drivers/gpu/drm/drm_atomic.c:2031 at __drm_atomic_helper_set_config+0x18e/0x1b0 [drm] Call Trace: drm_client_modeset_commit_atomic+0x16b/0x220 [drm] drm_client_modeset_commit_locked+0x56/0x160 [drm] drm_client_modeset_commit+0x21/0x40 [drm] __drm_fb_helper_restore_fbdev_mode_unlocked.part.0+0x7b/0x80 drm_fbdev_client_restore+0xe/0x20 [drm_client_lib] drm_client_dev_restore+0x9f/0xc0 [drm] drm_release+0xc5/0xe0 [drm] The warning is followed by a NULL pointer dereference: BUG: kernel NULL pointer dereference, address: 0000000000000008 RIP: __drm_fb_helper_restore_fbdev_mode_unlocked.part.0+0x41/0x80 [drm_kms_helper] Call Trace: drm_fbdev_client_restore+0xe/0x20 [drm_client_lib] drm_client_dev_restore+0x9f/0xc0 [drm] drm_release+0xc5/0xe0 [drm] __fput+0xdc/0x2b0 __x64_sys_close+0x39/0x80 do_syscall_64+0x8d/0x460 entry_SYSCALL_64_after_hwframe+0x76/0x7e drm_client_register() adds the DRM client to the device client list before invoking the initial hotplug callback. If the hotplug callback fails, the client remains registered. For the fbdev client, a failure during drm_fb_helper_initial_config() causes the partially initialized fbdev helper to be cleaned up. drm_fb_helper_fini() releases fb_helper->info and leaves it NULL. The fbdev client therefore remains registered even though there is no fully initialized framebuffer device. Later, when userspace closes the DRM file descriptor, drm_release() can invoke the restore callbacks of registered DRM clients: drm_release() drm_client_dev_restore() drm_fbdev_client_restore() drm_fb_helper_restore_fbdev_mode_unlocked() drm_fbdev_client_restore() currently restores the fbdev state unconditionally. For a partially initialized fbdev client this can submit an incomplete modeset state and subsequently access fbdev state which has not been initialized, resulting in the warning and NULL pointer dereference above. drm_fbdev_client_unregister() already uses fb_helper->info to distinguish a fully probed framebuffer device from a partially initialized client. Use the same condition in drm_fbdev_client_restore() and skip restore if no framebuffer device has been successfully initialized.