CVE-2026-63853: drm/amdgpu/vcn: set no_user_fence for VCN v4.0 enc ring
Noroxi assessment
Priority: Monitor (action score 31/100)
- 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: 0.17% (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 1286b6872de0aee1feeeaa6dbac86369806de9a5, 51f694221047c84fa185be98210eb2c354ffb8c6, 525cc9df654365c147ae61e5562cf599ea2257f7; azl3 kernel 6.6.152.1-1 on Azure Linux 3.0 Release Notes; 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 1286b6872de0aee1feeeaa6dbac86369806de9a5, 51f694221047c84fa185be98210eb2c354ffb8c6, 525cc9df654365c147ae61e5562cf599ea2257f7; azl3 kernel 6.6.152.1-1 on Azure Linux 3.0 Release Notes; 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/amdgpu/vcn: set no_user_fence for VCN v4.0 enc ring VCN encoder and decoder rings do not support 64-bit user fence writes, reject CS submissions with user fences. (cherry picked from commit fd852c048b46f9825e904a4f3f4538fe9d8827d9)
- Published
- Jul 19, 2026
- Updated
- Oct 30, 2026
- EPSS
- 0.1% · 7th percentile
- CWE
- CWE-20
Report tools
Action score
31
Low priority for now.
- CVSS
- 31 / 40 · 7.8 / 10
- CISA KEV
- 0 / 30 · Not listed
- EPSS
- 0 / 30 · 0.1%
CISA SSVC decision
- Exploitation
- none
- Automatable
- no
- Technical impact
- total
Vulnrichment: CISA's decision-tree inputs.
CNA vs NVD score
- NVD
- —
- CNA · Linux
- 7.8
- NVD has not scored this yet; the score shown is the CNA’s.
The score given by the assigning authority versus NVD’s independent score. A gap means the severity is contested.
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.
Is your version affected? Check itNoroxi 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.
| Vendor | Product | CPE |
|---|---|---|
| linux | linux kernel | cpe:2.3:o:linux:linux_kernel |
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
- 5.19affected
- 8da1170a16e4d4b49fa07d1f75ad480847ff7eca and later · before 772f83fc70b797ac88d696671780eaf175cc7f31affected · git
- 8da1170a16e4d4b49fa07d1f75ad480847ff7eca and later · before 525cc9df654365c147ae61e5562cf599ea2257f7affected · git
- 8da1170a16e4d4b49fa07d1f75ad480847ff7eca and later · before d8df8918677136b018d71d0b94a1f6b816715946affected · git
- 8da1170a16e4d4b49fa07d1f75ad480847ff7eca and later · before 1286b6872de0aee1feeeaa6dbac86369806de9a5affected · git
- 8da1170a16e4d4b49fa07d1f75ad480847ff7eca and later · before 6bdd2ed6458d35c368fbe9550a4d7f342abd3a92affected · git
- 8da1170a16e4d4b49fa07d1f75ad480847ff7eca and later · before 51f694221047c84fa185be98210eb2c354ffb8c6affected · git
- before 5.19not affected · semver
- 6.1.191 and later · up to and including 6.1.*not affected · semver
- 6.6.160 and later · up to and including 6.6.*not affected · semver
Affected versions · NVD (5)
NVD version ranges (for catalog products). Add the product to your stack with a version and matching uses these.
- linux linux kernel5.19 and later · before 6.6.160
- linux linux kernel6.7 and later · before 6.12.114
- linux linux kernel6.13 and later · before 6.18.33
- linux linux kernel6.19 and later · before 7.0.10
- linux linux kernel7.1
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 6.12.115-2 | 6.12.115-2 |
| Debian:14 | linux | before 7.0.10-1 | 7.0.10-1 |
Same product
linux: all recordsOther highest-scoring records for the same primary product.
- CVE-2026-31431crypto: algif_aead - Revert to operating out-of-placeKEV90Now
- 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…KEV89Now
- CVE-2021-22555Heap Out-Of-Bounds Write in Netfilter IP6T_SO_SET_REPLACEKEV85Now
Published before and after this one in the same product
- ← EarlierCVE-2026-63851Jul 19, 2026 · drm/amdgpu/vcn: set no_user_fence for VCN v4.0.5 enc ring31Monitor
- ← EarlierCVE-2026-63852Jul 19, 2026 · drm/amdgpu/vcn: set no_user_fence for VCN v4.0.3 enc ring31Monitor
- Later →CVE-2026-63854Jul 19, 2026 · drm/amdgpu/vcn: set no_user_fence for VCN v3.0 enc/dec rings31Monitor
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 | 1286b6872de0aee1feeeaa6dbac86369806de9a5 | Vendor (CNA) |
| Linux Linux | 51f694221047c84fa185be98210eb2c354ffb8c6 | Vendor (CNA) |
| Linux Linux | 525cc9df654365c147ae61e5562cf599ea2257f7 | Vendor (CNA) |
| Linux Linux | 6bdd2ed6458d35c368fbe9550a4d7f342abd3a92 | Vendor (CNA) |
| Linux Linux | 772f83fc70b797ac88d696671780eaf175cc7f31 | Vendor (CNA) |
| Linux Linux | d8df8918677136b018d71d0b94a1f6b816715946 | Vendor (CNA) |
| azl3 kernel 6.6.152.1-1 on Azure Linux 3.0 | Release Notes | Microsoft (MSRC) |
| azl3 kernel 6.6.157.1-1 on Azure Linux 3.0 | Release Notes | Microsoft (MSRC) |
| azl3 kernel 6.6.159.1-1 on Azure Linux 3.0 | 6.6.161.1-1 · Release Notes | Microsoft (MSRC) |
| debian:linux | 6.12.115-2 · Debian:13 | Package registry (OSV) |
| debian:linux | 7.0.10-1 · Debian:14 | 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.
No dated events beyond publication.
FIRST EPSS daily score; only changes of 0.01 or more are recorded (step chart).
Variant candidates
Same product, same weakness class, within 18 months. If the patch missed the root cause, the sibling bug is here.
- CVE-2026-640370 days apartwifi: iwlwifi: mld: fix TSO segmentation explosion when AMSDU is disabled39Monitor
- CVE-2026-640460 days apartnet: tls: prevent chain-after-chain in plain text SG39Monitor
- CVE-2026-5322124 days apartip6_vti: fix incorrect tunnel matching in vti6_tnl_lookup()39Monitor
- CVE-2026-4611552 days apartblock: add pgmap check to biovec_phys_mergeable39Monitor
- CVE-2026-4311474 days apartnetfilter: nft_set_pipapo_avx2: don't return non-matching entry on expiry37Monitor
- CVE-2026-641060 days apartKVM: arm64: vgic-its: Reject restored DTE with out-of-range num_eventid_bits36Monitor
National notice (Türkiye Cybersecurity Directorate / USOM)
Official security notices citing this record; remediation advice is on the agency's page.
- TR-26-0576 · Jul 20, 2026(Linux Kernel Güvenlik Bildirimi)
Not on record for this CVE: patch commit or PR link · researcher credit · public bounty program.
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
- high · data can be read
- Integrity
- high · data or configuration can be modified
- Availability
- high · the service can be disrupted
- Attack vector
- Local
- Attack complexity
- Low
- Privileges required
- Low
- User interaction
- None
- Scope
- Unchanged
- Confidentiality impact
- High
- Integrity impact
- High
- Availability impact
- High
Weakness class (CWE)
CWE-20 · Improper Input ValidationCVSS vector
CVSS:3.1/AV:L/AC:L/PR:L/UI:N/S:U/C:H/I:H/A:H
nvd-secondary
Attack context
MITRE CAPEC attack patterns and ATT&CK techniques for this weakness class (CWE). A starting point for detection rules and threat hunting.
Attack patterns (CAPEC)
- Buffer Overflow via Environment VariablesCAPEC-10likelihood: High · High
- Server Side Include (SSI) InjectionCAPEC-101likelihood: High · High
- Cross Zone ScriptingCAPEC-104likelihood: Medium · High
- Command Line Execution through SQL InjectionCAPEC-108likelihood: Low · Very High
- Object Relational Mapping InjectionCAPEC-109likelihood: Low · High
- SQL Injection through SOAP Parameter TamperingCAPEC-110likelihood: High · Very High
- Double EncodingCAPEC-120likelihood: Low · Medium
- Subverting Environment Variable ValuesCAPEC-13likelihood: High · Very High
ATT&CK techniques
- Obfuscated Files or InformationT1027
- Masquerading: Invalid Code SignatureT1036.001
- Steal Web Session CookieT1539
- Subvert Trust Controls: Code SigningT1553.002
- Impair Defenses:Impair Command History LoggingT1562.003
- Hijack Execution Flow:Dynamic Linker HijackingT1574.006
- Hijack Execution Flow:Path Interception by PATH Environment VariableT1574.007
Change log (2)
- SSVC exploitation— → none
- Fix✗ → ✓
For records you follow, these changes also arrive as notifications. →
References
Show all references (5 more)Show less
- git.kernel.org/stable/c/51f694221047c84fa185be98210eb2c354ffb8c6
- git.kernel.org/stable/c/525cc9df654365c147ae61e5562cf599ea2257f7
- git.kernel.org/stable/c/6bdd2ed6458d35c368fbe9550a4d7f342abd3a92
- git.kernel.org/stable/c/772f83fc70b797ac88d696671780eaf175cc7f31
- git.kernel.org/stable/c/d8df8918677136b018d71d0b94a1f6b816715946
Vendor advisories and official records. Exploit/PoC links are deliberately left out.