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NVD / CVE Program· CNA Linux

CVE-2025-38215: fbdev: Fix do_register_framebuffer to prevent null-ptr-deref in fb_videomode_to_var

Noroxi assessment

Priority: Monitor (action score 22/100)

  • 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).
  • Someone with local access to the system can trigger it. A low-privileged account is enough. No user action is required. No special conditions are required; it is repeatable.
  • Fixed version: Linux Linux 0909b2b49c4546a7a08c80f53d93736b63270827, 17186f1f90d34fa701e4f14e6818305151637b9e, 3f2098f4fba7718eb2501207ca6e99d22427f25a; azl3 kernel 6.6.92.2-2 on Azure Linux 3.0 6.6.96.1-1; azl3 kernel 6.6.96.1-1 on Azure Linux 3.0 6.6.96.1-1.

Low priority for now. Upgrade to Linux Linux 0909b2b49c4546a7a08c80f53d93736b63270827, 17186f1f90d34fa701e4f14e6818305151637b9e, 3f2098f4fba7718eb2501207ca6e99d22427f25a; azl3 kernel 6.6.92.2-2 on Azure Linux 3.0 6.6.96.1-1; azl3 kernel 6.6.96.1-1 on Azure Linux 3.0 6.6.96.1-1 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: fbdev: Fix do_register_framebuffer to prevent null-ptr-deref in fb_videomode_to_var If fb_add_videomode() in do_register_framebuffer() fails to allocate memory for fb_videomode, it will later lead to a null-ptr dereference in fb_videomode_to_var(), as the fb_info is registered while not having the mode in modelist that is expected to be there, i.e. the one that is described in fb_info->var. ================================================================ general protection fault, probably for non-canonical address 0xdffffc0000000001: 0000 [#1] PREEMPT SMP KASAN NOPTI KASAN: null-ptr-deref in range [0x0000000000000008-0x000000000000000f] CPU: 1 PID: 30371 Comm: syz-executor.1 Not tainted 5.10.226-syzkaller #0 Hardware name: QEMU Standard PC (i440FX + PIIX, 1996), BIOS 1.12.0-1 04/01/2014 RIP: 0010:fb_videomode_to_var+0x24/0x610 drivers/video/fbdev/core/modedb.c:901 Call Trace: display_to_var+0x3a/0x7c0 drivers/video/fbdev/core/fbcon.c:929 fbcon_resize+0x3e2/0x8f0 drivers/video/fbdev/core/fbcon.c:2071 resize_screen drivers/tty/vt/vt.c:1176 [inline] vc_do_resize+0x53a/0x1170 drivers/tty/vt/vt.c:1263 fbcon_modechanged+0x3ac/0x6e0 drivers/video/fbdev/core/fbcon.c:2720 fbcon_update_vcs+0x43/0x60 drivers/video/fbdev/core/fbcon.c:2776 do_fb_ioctl+0x6d2/0x740 drivers/video/fbdev/core/fbmem.c:1128 fb_ioctl+0xe7/0x150 drivers/video/fbdev/core/fbmem.c:1203 vfs_ioctl fs/ioctl.c:48 [inline] __do_sys_ioctl fs/ioctl.c:753 [inline] __se_sys_ioctl fs/ioctl.c:739 [inline] __x64_sys_ioctl+0x19a/0x210 fs/ioctl.c:739 do_syscall_64+0x33/0x40 arch/x86/entry/common.c:46 entry_SYSCALL_64_after_hwframe+0x67/0xd1 ================================================================ Even though fbcon_init() checks beforehand if fb_match_mode() in var_to_display() fails, it can not prevent the panic because fbcon_init() does not return error code. Considering this and the comment in the code about fb_match_mode() returning NULL - "This should not happen" - it is better to prevent registering the fb_info if its mode was not set successfully. Also move fb_add_videomode() closer to the beginning of do_register_framebuffer() to avoid having to do the cleanup on fail. Found by Linux Verification Center (linuxtesting.org) with Syzkaller.

MediumCVSS 5.5 · v3.1—No exploit Fix available
Published
Jul 4, 2025
Updated
Oct 15, 2026
EPSS
0.1% · 6th percentile

Report tools

JSON

Action score

22

Monitor

Low priority for now.

CVSS
22 / 40 · 5.5 / 10
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

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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.

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Affected 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.

VendorProduct
linuxlinux kernel
debiandebian linux

Affected versions

NVD version ranges (for catalog products). Add the product to your stack with a version and matching uses these.

  • debian debian linux11.0
  • linux linux kernel2.6.13 and later · before 6.1.143
  • linux linux kernel6.2 and later · before 6.6.95
  • linux linux kernel6.7 and later · before 6.12.35
  • linux linux kernel6.13 and later · before 6.15.4
  • linux linux kernel2.6.12

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

    • 2.6.12affected
    • 1da177e4c3f41524e886b7f1b8a0c1fc7321cac2 and later · before 908c5bb64f9c4319902b8ca1aa3fef8f83302520affected · git
    • 1da177e4c3f41524e886b7f1b8a0c1fc7321cac2 and later · before 0909b2b49c4546a7a08c80f53d93736b63270827affected · git
    • 1da177e4c3f41524e886b7f1b8a0c1fc7321cac2 and later · before 3f2098f4fba7718eb2501207ca6e99d22427f25aaffected · git
    • 1da177e4c3f41524e886b7f1b8a0c1fc7321cac2 and later · before d803c4c2a4ac8ce2be6d899d5c7ab0bf7ec355e9affected · git
    • 1da177e4c3f41524e886b7f1b8a0c1fc7321cac2 and later · before 17186f1f90d34fa701e4f14e6818305151637b9eaffected · git
    • before 2.6.12not affected · semver
    • 6.1.143 and later · up to and including 6.1.*not affected · semver
    • 6.6.95 and later · up to and including 6.6.*not affected · semver
    • 6.12.35 and later · up to and including 6.12.*not affected · semver

Package-level exposure

OSV and GitHub Advisory data: ecosystem, package and range. SBOM matching uses this table.

EcosystemPackageAffected rangeFix
Debian:12linuxbefore 6.1.147-16.1.147-1
Debian:13linuxbefore 6.12.35-16.12.35-1

Same product

linux: all records

Other highest-scoring records for the same primary product.

  • CVE-2026-31431crypto: algif_aead - Revert to operating out-of-placeKEV
    90Now
  • CVE-2022-0847A flaw was found in the way the "flags" member of the new pipe buffer structure was lacking proper initialization in copy_page_to_iter_pipe KEV
    89Now
  • CVE-2021-22555Heap Out-Of-Bounds Write in Netfilter IP6T_SO_SET_REPLACEKEV
    85Now

Published before and after this one in the same product

  • ← EarlierCVE-2025-38211Jul 4, 2025 · RDMA/iwcm: Fix use-after-free of work objects after cm_id destruction
    31Monitor
  • ← EarlierCVE-2025-38214Jul 4, 2025 · fbdev: Fix fb_set_var to prevent null-ptr-deref in fb_videomode_to_var
    22Monitor
  • Later →CVE-2025-38217Jul 4, 2025 · hwmon: (ftsteutates) Fix TOCTOU race in fts_read()
    18Monitor

Remediation

Which version to upgrade to

Fix versions compiled from the vendor, package registries and Microsoft. Verify the vendor's note before upgrading.

Product / packageFixed versionSource
Linux Linux0909b2b49c4546a7a08c80f53d93736b63270827Vendor (CNA)
Linux Linux17186f1f90d34fa701e4f14e6818305151637b9eVendor (CNA)
Linux Linux3f2098f4fba7718eb2501207ca6e99d22427f25aVendor (CNA)
Linux Linux908c5bb64f9c4319902b8ca1aa3fef8f83302520Vendor (CNA)
Linux Linuxd803c4c2a4ac8ce2be6d899d5c7ab0bf7ec355e9Vendor (CNA)
azl3 kernel 6.6.92.2-2 on Azure Linux 3.06.6.96.1-1 · CBL-Mariner ReleasesMicrosoft (MSRC)
azl3 kernel 6.6.96.1-1 on Azure Linux 3.06.6.96.1-1 · CBL-Mariner ReleasesMicrosoft (MSRC)
cbl2 kernel 5.15.202.1-1 on CBL-Mariner 2.0Release NotesMicrosoft (MSRC)
debian:linux6.1.147-1 · Debian:12Package 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.

No dated events beyond publication.

No history yet (it accumulates with the daily EPSS job).

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 researchers

Finders, 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.

—

Bug bounty scope

No known public program.

Source: bounty-targets-data (public HackerOne, Bugcrowd, Intigriti, YesWeHack listings).

Technical details

Attack conditions

  • Someone with local access to the system can trigger it.
  • A low-privileged account is enough.
  • No user action is required.
  • No special conditions are required; it is repeatable.

If successful

Confidentiality
none
Integrity
none
Availability
high · the service can be disrupted
Attack vector
Local
Attack complexity
Low
Privileges required
Low
User interaction
None
Scope
Unchanged
Confidentiality impact
None
Integrity impact
None
Availability impact
High

Weakness class (CWE)

CWE-476 · NULL Pointer Dereference

CVSS vector

CVSS:3.1/AV:L/AC:L/PR:L/UI:N/S:U/C:N/I:N/A:H

nvd-primary

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

  1. Fix✗ → ✓

For records you follow, these changes also arrive as notifications. →

References

Show all references (6 more)

Vendor advisories and official records. Exploit/PoC links are deliberately left out.

All records