CVE-2026-99007: drm/fb-helper: defer setup when fbdev_probe() fails, not just on -EAGAIN
Noroxi assessment
Priority: Monitor (action score 0/100)
- The sources we track (CISA KEV, Exploit-DB, Metasploit, Nuclei, GitHub) show no public exploit code or exploitation in the wild.
- Probability of exploitation in the next 30 days: 0.16% (FIRST EPSS).
- Fixed version: Linux Linux 3b303696f61461b3569019d7fcac6a646652b2b4, 4a2006c675758f0c765b36fec6b49d17e89159cf, 4e7b508c7c60dec7a86b7eb2a1b7e6d174afa457; azl3 kernel 6.6.157.1-1 on Azure Linux 3.0 Release Notes.
- Mentioned 1 time in Turkish national cyber security advisories (siberguvenlik.gov.tr).
Low priority for now. Upgrade to Linux Linux 3b303696f61461b3569019d7fcac6a646652b2b4, 4a2006c675758f0c765b36fec6b49d17e89159cf, 4e7b508c7c60dec7a86b7eb2a1b7e6d174afa457; azl3 kernel 6.6.157.1-1 on Azure Linux 3.0 Release Notes or later.
Generated automatically from the record's data: CVSS (NVD and CNA), CISA KEV and SSVC, FIRST EPSS, exploit sources, fixed versions. How we calculate it
Primary sources: NVD · CVE.org · FIRST EPSS
In the Linux kernel, the following vulnerability has been resolved: drm/fb-helper: defer setup when fbdev_probe() fails, not just on -EAGAIN __drm_fb_helper_initial_config_and_unlock() calls drm_client_modeset_probe() first, which already fills in each mode_set->mode/num_connectors for every connected output, and only afterwards calls drm_fb_helper_single_fb_probe() to create fb_helper->fb and wire it into those mode_sets via drm_setup_crtcs_fb(). If drm_fb_helper_single_fb_probe() fails with anything other than -EAGAIN (e.g. dev->driver->fbdev_probe() itself fails), the function bails out before drm_setup_crtcs_fb() runs and before setting fb_helper->deferred_setup. The client is left with mode_sets that have a mode and connectors but mode_set->fb == NULL, and nothing marks this fb_helper as needing a retry. __drm_fb_helper_restore_fbdev_mode_unlocked() only skips committing when fb_helper->deferred_setup is set, so a later .restore() call (drm_lastclose() on process exit, in this report) commits the stale mode_set through drm_client_modeset_commit() -> drm_client_modeset_commit_atomic() -> __drm_atomic_helper_set_config(), which hits WARN_ON(!set->fb). Mark fb_helper->deferred_setup on any drm_fb_helper_single_fb_probe() failure, not just -EAGAIN, so restore keeps skipping the commit until a later hotplug event successfully re-probes and re-populates mode_set->fb. The real error code is still returned to the caller unchanged.
- Published
- Oct 23, 2026
- Updated
- Oct 23, 2026
- EPSS
- 0.1% · 6th percentile
- CWE
- —
Report tools
Action score
0
Monitor
Low priority for now.
- CVSS
- 0 / 40 · —
- CISA KEV
- 0 / 30 · Not listed
- EPSS
- 0 / 30 · 0.1%
Get told when this record changes
- Not in KEV: no record of exploitation in the wild
- No public exploit code on record
- A fix has been released
If any of these changes, we'll tell you in the daily email digest.
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Noroxi analysis
What does it mean in your environment?
The assessment above is generated automatically from the record's data; it doesn't know your environment. Our team verifies on your systems whether this vulnerability is actually exploitable and which mitigation is enough.
We use this product, ask for helpAffected systems
Is your version affected?
Pick the product and type the version you run. It's compared with this record's version ranges in your browser; the version isn't sent anywhere.
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Versions reported by the vendor
Affected version ranges reported by the assigning authority (Linux). Independent of NVD's CPE analysis and usually ahead of it.
Linux Linux
- 4.14affected
- ca91a2758fcef6635626993557dd51cfbb6dd134 and later · before 4a2006c675758f0c765b36fec6b49d17e89159cfaffected · git
- ca91a2758fcef6635626993557dd51cfbb6dd134 and later · before 3b303696f61461b3569019d7fcac6a646652b2b4affected · git
- ca91a2758fcef6635626993557dd51cfbb6dd134 and later · before 4e7b508c7c60dec7a86b7eb2a1b7e6d174afa457affected · git
- ca91a2758fcef6635626993557dd51cfbb6dd134 and later · before d510ed273854177f0a3ed330145858b2fe667f81affected · git
- ca91a2758fcef6635626993557dd51cfbb6dd134 and later · before 755c94d178b7e972bb766199d34e4ba4f63a89ebaffected · git
- before 4.14not affected · semver
- 6.6.160 and later · up to and including 6.6.*not affected · semver
- 6.12.113 and later · up to and including 6.12.*not affected · semver
- 6.18.57 and later · up to and including 6.18.*not affected · semver
Package-level exposure
OSV and GitHub Advisory data: ecosystem, package and range. SBOM matching uses this table.
| Ecosystem | Package | Affected range | Fix |
|---|---|---|---|
| Debian:12 | linux | from 0 | — |
| Debian:13 | linux | before 6.12.113-1 | 6.12.113-1 |
| Debian:14 | linux | before 7.2.11-1 | 7.2.11-1 |
Same product
linux: all recordsOther highest-scoring records for the same primary product.
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Published before and after this one in the same product
- ← EarlierCVE-2026-99005Oct 23, 2026 · drm/i915/gt: Unmask interrupts only when ACTIVE is true0Monitor
- ← EarlierCVE-2026-99006Oct 23, 2026 · drm/i915/gem: Prevent overstepping exec array boundary31Monitor
- Later →CVE-2026-99008Oct 23, 2026 · Bluetooth: RFCOMM: Fix NULL tty_dev dereference in rfcomm_dev_shutdown0Monitor
Remediation
Which version to upgrade to
Fix versions compiled from the vendor, package registries and Microsoft. Verify the vendor's note before upgrading.
| Product / package | Fixed version | Source |
|---|---|---|
| Linux Linux | 3b303696f61461b3569019d7fcac6a646652b2b4 | Vendor (CNA) |
| Linux Linux | 4a2006c675758f0c765b36fec6b49d17e89159cf | Vendor (CNA) |
| Linux Linux | 4e7b508c7c60dec7a86b7eb2a1b7e6d174afa457 | Vendor (CNA) |
| Linux Linux | 755c94d178b7e972bb766199d34e4ba4f63a89eb | Vendor (CNA) |
| Linux Linux | d510ed273854177f0a3ed330145858b2fe667f81 | Vendor (CNA) |
| azl3 kernel 6.6.157.1-1 on Azure Linux 3.0 | Release Notes | Microsoft (MSRC) |
| debian:linux | 6.12.113-1 · Debian:13 | Package registry (OSV) |
Exploit status
No known public exploit
No public exploit has been observed yet. That doesn't mean you're safe, only that the bar is a little higher.
Research context
For pentesters and researchers: attack profile, score disagreement, timeline, patch commits, credits, variant and chain candidates, bug bounty scope. All derived from existing data; no exploit code.
Timeline
From publication to today: proof of concept, Metasploit module, CISA KEV and fix record. Dates are as reported by the sources.
- Published
- Fix recordedsame day
- TodayOct 28, 2026+5 d
FIRST EPSS daily score; only changes of 0.01 or more are recorded (step chart).
Patch and commit links
Commit, PR and diff links among the references. A starting point for patch-diffing and variant hunting; fixes, not exploits.
No commit or PR link among the references.
Credits
All researchersFinders, reporters and analysts named in the CNA record. Click a name for that researcher’s other records.
No credits in the CNA record.
Variant candidates
Same product, same weakness class, within 18 months. If the patch missed the root cause, the sibling bug is here.
No nightly-computed relations.
Chain candidates
An authentication bypass and a privilege-requiring bug in the same product, published close together: combined they may become an unauthenticated path.
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Bug bounty scope
No known public program.
Source: bounty-targets-data (public HackerOne, Bugcrowd, Intigriti, YesWeHack listings).
National notice (Türkiye Cybersecurity Directorate / USOM)
Official security notices citing this record; remediation advice is on the agency's page.
- TR-26-1390 · Oct 26, 2026(Linux Kernel Güvenlik Bildirimi)
Technical details
No CVSS vector for this record, so attack conditions can't be derived.
Weakness class (CWE)
—
Attack context
MITRE CAPEC attack patterns and ATT&CK techniques for this weakness class (CWE). A starting point for detection rules and threat hunting.
MITRE has no CAPEC/ATT&CK mapping for this CWE.
Change log
- Exploit maturity— → none
- Fix✗ → ✓
For records you follow, these changes also arrive as notifications. →
References
Show all references (4 more)Show less
Vendor advisories and official records. Exploit/PoC links are deliberately left out.