CVE-2026-68299: vmxnet3: fix BUG_ON in vmxnet3_get_hdr_len() for Geneve packets
Noroxi assessment
Priority: Monitor (action score 30/100)
- 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: 0.50% (FIRST EPSS).
- Anyone who can reach it over the internet can trigger it. No account or password is required. No user action is required. No special conditions are required; it is repeatable.
- According to CISA the attack is automatable: targets can be found by mass scanning.
- Fixed version: Linux Linux 28cb5d8d13b4c1faf3f688f62e5df82fe7b438d8, 28e382646417c7e2be9c9a7079eddf627ff52b90, 2ddf51fcb6dd7d55ceef38e2e1a5ab2ab7fd47b0; azl3 kernel 6.6.143.1-1 on Azure Linux 3.0 6.6.150.1-1.
- Mentioned 1 time in Turkish national cyber security advisories (siberguvenlik.gov.tr).
Low priority for now. Upgrade to Linux Linux 28cb5d8d13b4c1faf3f688f62e5df82fe7b438d8, 28e382646417c7e2be9c9a7079eddf627ff52b90, 2ddf51fcb6dd7d55ceef38e2e1a5ab2ab7fd47b0; azl3 kernel 6.6.143.1-1 on Azure Linux 3.0 6.6.150.1-1 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: vmxnet3: fix BUG_ON in vmxnet3_get_hdr_len() for Geneve packets vmxnet3_get_hdr_len() assumes gdesc->rcd.v4/v6/tcp always describe the outer header, but for a Geneve-encapsulated packet the device can set them based on the inner header instead, signalled by the VMXNET3_RCD_HDR_INNER_SHIFT bit in the completion descriptor. Since the function never skips the outer encapsulation, this mismatch triggers: - BUG_ON(hdr.ipv4->protocol != IPPROTO_TCP), because the outer protocol is UDP (Geneve), not TCP. - BUG_ON(hdr.eth->h_proto != ...), when the tunnel's outer and inner IP versions differ (e.g. outer IPv6/inner IPv4 or vice versa). Check VMXNET3_RCD_HDR_INNER_SHIFT up front and bail out, since the function cannot locate the inner header it would need to parse. Also convert the remaining BUG_ON()s in this function to return 0 defensively.
- Published
- Aug 10, 2026
- Updated
- Oct 19, 2026
- EPSS
- 0.5% · 42th percentile
- CWE
- CWE-20
Report tools
Action score
30
Monitor
Low priority for now.
- CVSS
- 30 / 40 · 7.5 / 10
- CISA KEV
- 0 / 30 · Not listed
- EPSS
- 0 / 30 · 0.5%
CISA SSVC decision
- Exploitation
- none
- Automatable
- yes
- Technical impact
- partial
Vulnrichment: CISA's decision-tree inputs.
CNA vs NVD score
- NVD
- —
- CNA · Linux
- 7.5
- 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.
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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.
—
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
- 4.2affected
- 45dac1d6ea045ae56e4df8d9c70c92c7412bd4fc and later · before 2ddf51fcb6dd7d55ceef38e2e1a5ab2ab7fd47b0affected · git
- 45dac1d6ea045ae56e4df8d9c70c92c7412bd4fc and later · before fbab6b73cc086e32698c86e43d1b16bf17d24c36affected · git
- 45dac1d6ea045ae56e4df8d9c70c92c7412bd4fc and later · before 28e382646417c7e2be9c9a7079eddf627ff52b90affected · git
- 45dac1d6ea045ae56e4df8d9c70c92c7412bd4fc and later · before 667b6e52048eaf4dbcf1707ed87ffd44abb9cb38affected · git
- 45dac1d6ea045ae56e4df8d9c70c92c7412bd4fc and later · before 28cb5d8d13b4c1faf3f688f62e5df82fe7b438d8affected · git
- 45dac1d6ea045ae56e4df8d9c70c92c7412bd4fc and later · before 4fdb0f162ccdbe9626863b10003855703253fa29affected · git
- 45dac1d6ea045ae56e4df8d9c70c92c7412bd4fc and later · before b28596baf87e25a078789f1c05817c8a3bf71257affected · git
- 45dac1d6ea045ae56e4df8d9c70c92c7412bd4fc and later · before 34a71f5361fc3adb5b7138da78750b0d535a8252affected · git
- before 4.2not affected · semver
Package-level exposure
OSV and GitHub Advisory data: ecosystem, package and range. SBOM matching uses this table.
| Ecosystem | Package | Affected range | Fix |
|---|---|---|---|
| AlmaLinux:10 | kernel | before 6.12.0-211.61.1.el10_2 | 6.12.0-211.61.1.el10_2 |
| AlmaLinux:10 | kernel-64k | before 6.12.0-211.61.1.el10_2 | 6.12.0-211.61.1.el10_2 |
| AlmaLinux:10 | kernel-64k-core | before 6.12.0-211.61.1.el10_2 | 6.12.0-211.61.1.el10_2 |
| AlmaLinux:10 | kernel-64k-debug | before 6.12.0-211.61.1.el10_2 | 6.12.0-211.61.1.el10_2 |
| AlmaLinux:10 | kernel-64k-debug-core | before 6.12.0-211.61.1.el10_2 | 6.12.0-211.61.1.el10_2 |
| AlmaLinux:10 | kernel-64k-debug-devel | before 6.12.0-211.61.1.el10_2 | 6.12.0-211.61.1.el10_2 |
| AlmaLinux:10 | kernel-64k-debug-devel-matched | before 6.12.0-211.61.1.el10_2 | 6.12.0-211.61.1.el10_2 |
| AlmaLinux:10 | kernel-64k-debug-modules | before 6.12.0-211.61.1.el10_2 | 6.12.0-211.61.1.el10_2 |
| AlmaLinux:10 | kernel-64k-debug-modules-core | before 6.12.0-211.61.1.el10_2 | 6.12.0-211.61.1.el10_2 |
| AlmaLinux:10 | kernel-64k-debug-modules-extra | before 6.12.0-211.61.1.el10_2 | 6.12.0-211.61.1.el10_2 |
| AlmaLinux:10 | kernel-64k-devel | before 6.12.0-211.61.1.el10_2 | 6.12.0-211.61.1.el10_2 |
| AlmaLinux:10 | kernel-64k-devel-matched | before 6.12.0-211.61.1.el10_2 | 6.12.0-211.61.1.el10_2 |
| AlmaLinux:10 | kernel-64k-modules | before 6.12.0-211.61.1.el10_2 | 6.12.0-211.61.1.el10_2 |
| AlmaLinux:10 | kernel-64k-modules-core | before 6.12.0-211.61.1.el10_2 | 6.12.0-211.61.1.el10_2 |
| AlmaLinux:10 | kernel-64k-modules-extra | before 6.12.0-211.61.1.el10_2 | 6.12.0-211.61.1.el10_2 |
| AlmaLinux:10 | kernel-abi-stablelists | before 6.12.0-211.61.1.el10_2 | 6.12.0-211.61.1.el10_2 |
| AlmaLinux:10 | kernel-core | before 6.12.0-211.61.1.el10_2 | 6.12.0-211.61.1.el10_2 |
| AlmaLinux:10 | kernel-cross-headers | before 6.12.0-211.61.1.el10_2 | 6.12.0-211.61.1.el10_2 |
| AlmaLinux:10 | kernel-debug | before 6.12.0-211.61.1.el10_2 | 6.12.0-211.61.1.el10_2 |
| AlmaLinux:10 | kernel-debug-core | before 6.12.0-211.61.1.el10_2 | 6.12.0-211.61.1.el10_2 |
| AlmaLinux:10 | kernel-debug-devel | before 6.12.0-211.61.1.el10_2 | 6.12.0-211.61.1.el10_2 |
| AlmaLinux:10 | kernel-debug-devel-matched | before 6.12.0-211.61.1.el10_2 | 6.12.0-211.61.1.el10_2 |
| AlmaLinux:10 | kernel-debug-modules | before 6.12.0-211.61.1.el10_2 | 6.12.0-211.61.1.el10_2 |
| AlmaLinux:10 | kernel-debug-modules-core | before 6.12.0-211.61.1.el10_2 | 6.12.0-211.61.1.el10_2 |
+96
Same product
linux: all recordsOther highest-scoring records for the same primary product.
- CVE-2026-74705udp: fix potential use-after-free in tunnel segmentation40Plan
- CVE-2026-74612veth: fix skb length accounting after XDP frag adjustment40Plan
- CVE-2026-74475vxlan: use neigh_ha_snapshot() in route_shortcircuit()40Plan
Published before and after this one in the same product
- ← EarlierCVE-2026-68297Aug 10, 2026 · tipc: fix u16 MTU truncation in media and bearer MTU validation31Monitor
- ← EarlierCVE-2026-68298Aug 10, 2026 · drm/xe/vm: Fix SVM leak on resv obj alloc failure in xe_vm_create()31Monitor
- Later →CVE-2026-68300Aug 10, 2026 · sctp: auth: verify auth requirement when auth_chunk is NULL39Monitor
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 | 28cb5d8d13b4c1faf3f688f62e5df82fe7b438d8 | Vendor (CNA) |
| Linux Linux | 28e382646417c7e2be9c9a7079eddf627ff52b90 | Vendor (CNA) |
| Linux Linux | 2ddf51fcb6dd7d55ceef38e2e1a5ab2ab7fd47b0 | Vendor (CNA) |
| Linux Linux | 34a71f5361fc3adb5b7138da78750b0d535a8252 | Vendor (CNA) |
| Linux Linux | 4fdb0f162ccdbe9626863b10003855703253fa29 | Vendor (CNA) |
| Linux Linux | 667b6e52048eaf4dbcf1707ed87ffd44abb9cb38 | Vendor (CNA) |
| Linux Linux | b28596baf87e25a078789f1c05817c8a3bf71257 | Vendor (CNA) |
| Linux Linux | fbab6b73cc086e32698c86e43d1b16bf17d24c36 | Vendor (CNA) |
| azl3 kernel 6.6.143.1-1 on Azure Linux 3.0 | 6.6.150.1-1 · CBL-Mariner Releases | Microsoft (MSRC) |
| almalinux:bpftool | 4.18.0-553.170.1.el8_10 · AlmaLinux:8 | Package registry (OSV) |
| almalinux:kernel | 4.18.0-553.170.1.el8_10 · AlmaLinux:8 | Package registry (OSV) |
| almalinux:kernel | 6.12.0-211.61.1.el10_2 · AlmaLinux:10 | Package registry (OSV) |
| almalinux:kernel-64k | 6.12.0-211.61.1.el10_2 · AlmaLinux:10 | Package registry (OSV) |
| almalinux:kernel-64k-core | 6.12.0-211.61.1.el10_2 · AlmaLinux:10 | Package registry (OSV) |
| almalinux:kernel-64k-debug | 6.12.0-211.61.1.el10_2 · AlmaLinux:10 | Package registry (OSV) |
| almalinux:kernel-64k-debug-core | 6.12.0-211.61.1.el10_2 · AlmaLinux:10 | Package registry (OSV) |
| almalinux:kernel-64k-debug-devel | 6.12.0-211.61.1.el10_2 · AlmaLinux:10 | Package registry (OSV) |
| almalinux:kernel-64k-debug-devel-matched | 6.12.0-211.61.1.el10_2 · AlmaLinux:10 | Package registry (OSV) |
| almalinux:kernel-64k-debug-modules | 6.12.0-211.61.1.el10_2 · AlmaLinux:10 | Package registry (OSV) |
| almalinux:kernel-64k-debug-modules-core | 6.12.0-211.61.1.el10_2 · AlmaLinux:10 | Package registry (OSV) |
| almalinux:kernel-64k-debug-modules-extra | 6.12.0-211.61.1.el10_2 · AlmaLinux:10 | Package registry (OSV) |
| almalinux:kernel-64k-devel | 6.12.0-211.61.1.el10_2 · AlmaLinux:10 | Package registry (OSV) |
| almalinux:kernel-64k-devel-matched | 6.12.0-211.61.1.el10_2 · AlmaLinux:10 | Package registry (OSV) |
| almalinux:kernel-rt | 4.18.0-553.170.1.rt7.511.el8_10 · AlmaLinux:8 | Package registry (OSV) |
| almalinux:kernel-rt-core | 4.18.0-553.170.1.rt7.511.el8_10 · AlmaLinux:8 | Package registry (OSV) |
| almalinux:kernel-rt-debug | 4.18.0-553.170.1.rt7.511.el8_10 · AlmaLinux:8 | Package registry (OSV) |
| almalinux:kernel-rt-debug-core | 4.18.0-553.170.1.rt7.511.el8_10 · AlmaLinux:8 | Package registry (OSV) |
| almalinux:kernel-rt-debug-devel | 4.18.0-553.170.1.rt7.511.el8_10 · AlmaLinux:8 | Package registry (OSV) |
| almalinux:kernel-rt-debug-modules | 4.18.0-553.170.1.rt7.511.el8_10 · AlmaLinux:8 | Package registry (OSV) |
| almalinux:kernel-rt-debug-modules-extra | 4.18.0-553.170.1.rt7.511.el8_10 · AlmaLinux:8 | Package registry (OSV) |
+19
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).
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.
- CVE-2026-681540 days apartlibceph: reject zero bucket types in crush_decode39Monitor
- CVE-2026-684775 days apartipvs: fix more places with wrong ipv6 transport offsets39Monitor
- CVE-2026-720655 days apartnet: mana: Validate the packet length reported by the NIC39Monitor
- CVE-2026-9999966 days apartipv4: validate checksum_start before completing checksum37Monitor
- CVE-2026-681990 days apartwifi: ath6kl: fix OOB access from firmware ADDBA window size35Monitor
- CVE-2026-684543 days apartKVM: s390: pci: Fix handling of AIF enable without AISB35Monitor
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).
National notice (Türkiye Cybersecurity Directorate / USOM)
Official security notices citing this record; remediation advice is on the agency's page.
- TR-26-0800 · Aug 11, 2026(Linux Kernel Güvenlik Bildirimi)
Technical details
Attack conditions
- Anyone who can reach it over the internet can trigger it.
- No account or password is required.
- 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
- Network
- Attack complexity
- Low
- Privileges required
- None
- User interaction
- None
- Scope
- Unchanged
- Confidentiality impact
- None
- Integrity impact
- None
- Availability impact
- High
Weakness class (CWE)
CWE-20 · Improper Input ValidationCVSS vector
CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/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
- SSVC exploitation— → none
- Fix✗ → ✓
For records you follow, these changes also arrive as notifications. →
References
Show all references (7 more)Show less
- git.kernel.org/stable/c/28e382646417c7e2be9c9a7079eddf627ff52b90
- git.kernel.org/stable/c/2ddf51fcb6dd7d55ceef38e2e1a5ab2ab7fd47b0
- git.kernel.org/stable/c/34a71f5361fc3adb5b7138da78750b0d535a8252
- git.kernel.org/stable/c/4fdb0f162ccdbe9626863b10003855703253fa29
- git.kernel.org/stable/c/667b6e52048eaf4dbcf1707ed87ffd44abb9cb38
- git.kernel.org/stable/c/b28596baf87e25a078789f1c05817c8a3bf71257
- git.kernel.org/stable/c/fbab6b73cc086e32698c86e43d1b16bf17d24c36
Vendor advisories and official records. Exploit/PoC links are deliberately left out.