CVE-2026-68299
vmxnet3: fix BUG_ON in vmxnet3_get_hdr_len() for Geneve packets
Description
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.
INFO
Published Date :
Aug. 10, 2026, 1:20 p.m.
Last Modified :
Aug. 17, 2026, 5:18 a.m.
Remotely Exploit :
Yes !
Source :
416baaa9-dc9f-4396-8d5f-8c081fb06d67
CVSS Scores
| Score | Version | Severity | Vector | Exploitability Score | Impact Score | Source |
|---|---|---|---|---|---|---|
| CVSS 3.1 | HIGH | 416baaa9-dc9f-4396-8d5f-8c081fb06d67 |
Solution
- Update the Linux kernel to the latest version.
- Reboot the system after the update.
- Verify the patch is applied.
References to Advisories, Solutions, and Tools
Here, you will find a curated list of external links that provide in-depth
information, practical solutions, and valuable tools related to
CVE-2026-68299.
CWE - Common Weakness Enumeration
While CVE identifies
specific instances of vulnerabilities, CWE categorizes the common flaws or
weaknesses that can lead to vulnerabilities. CVE-2026-68299 is
associated with the following CWEs:
Common Attack Pattern Enumeration and Classification (CAPEC)
Common Attack Pattern Enumeration and Classification
(CAPEC)
stores attack patterns, which are descriptions of the common attributes and
approaches employed by adversaries to exploit the CVE-2026-68299
weaknesses.
We scan GitHub repositories to detect new proof-of-concept exploits. Following list is a collection of public exploits and proof-of-concepts, which have been published on GitHub (sorted by the most recently updated).
Results are limited to the first 15 repositories due to potential performance issues.
The following list is the news that have been mention
CVE-2026-68299 vulnerability anywhere in the article.
The following table lists the changes that have been made to the
CVE-2026-68299 vulnerability over time.
Vulnerability history details can be useful for understanding the evolution of a vulnerability, and for identifying the most recent changes that may impact the vulnerability's severity, exploitability, or other characteristics.
-
CVE Modified by 416baaa9-dc9f-4396-8d5f-8c081fb06d67
Aug. 17, 2026
Action Type Old Value New Value Changed Affected [{'repo': 'https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git', 'vendor': 'Linux', 'product': 'Linux', 'versions': [{'status': 'affected', 'version': '45dac1d6ea045ae56e4df8d9c70c92c7412bd4fc', 'lessThan': '667b6e52048eaf4dbcf1707ed87ffd44abb9cb38', 'versionType': 'git'}, {'status': 'affected', 'version': '45dac1d6ea045ae56e4df8d9c70c92c7412bd4fc', 'lessThan': '28cb5d8d13b4c1faf3f688f62e5df82fe7b438d8', 'versionType': 'git'}, {'status': 'affected', 'version': '45dac1d6ea045ae56e4df8d9c70c92c7412bd4fc', 'lessThan': '4fdb0f162ccdbe9626863b10003855703253fa29', 'versionType': 'git'}, {'status': 'affected', 'version': '45dac1d6ea045ae56e4df8d9c70c92c7412bd4fc', 'lessThan': 'b28596baf87e25a078789f1c05817c8a3bf71257', 'versionType': 'git'}, {'status': 'affected', 'version': '45dac1d6ea045ae56e4df8d9c70c92c7412bd4fc', 'lessThan': '34a71f5361fc3adb5b7138da78750b0d535a8252', 'versionType': 'git'}], 'programFiles': ['drivers/net/vmxnet3/vmxnet3_drv.c'], 'defaultStatus': 'unaffected'}, {'repo': 'https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git', 'vendor': 'Linux', 'product': 'Linux', 'versions': [{'status': 'affected', 'version': '4.2'}, {'status': 'unaffected', 'version': '0', 'lessThan': '4.2', 'versionType': 'semver'}, {'status': 'unaffected', 'version': '6.6.148', 'versionType': 'semver', 'lessThanOrEqual': '6.6.*'}, {'status': 'unaffected', 'version': '6.12.101', 'versionType': 'semver', 'lessThanOrEqual': '6.12.*'}, {'status': 'unaffected', 'version': '6.18.42', 'versionType': 'semver', 'lessThanOrEqual': '6.18.*'}, {'status': 'unaffected', 'version': '7.1.6', 'versionType': 'semver', 'lessThanOrEqual': '7.1.*'}, {'status': 'unaffected', 'version': '7.2-rc5', 'versionType': 'original_commit_for_fix', 'lessThanOrEqual': '*'}], 'programFiles': ['drivers/net/vmxnet3/vmxnet3_drv.c'], 'defaultStatus': 'affected'}] [{'repo': 'https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git', 'vendor': 'Linux', 'product': 'Linux', 'versions': [{'status': 'affected', 'version': '45dac1d6ea045ae56e4df8d9c70c92c7412bd4fc', 'lessThan': '667b6e52048eaf4dbcf1707ed87ffd44abb9cb38', 'versionType': 'git'}, {'status': 'affected', 'version': '45dac1d6ea045ae56e4df8d9c70c92c7412bd4fc', 'lessThan': '28cb5d8d13b4c1faf3f688f62e5df82fe7b438d8', 'versionType': 'git'}, {'status': 'affected', 'version': '45dac1d6ea045ae56e4df8d9c70c92c7412bd4fc', 'lessThan': '4fdb0f162ccdbe9626863b10003855703253fa29', 'versionType': 'git'}, {'status': 'affected', 'version': '45dac1d6ea045ae56e4df8d9c70c92c7412bd4fc', 'lessThan': 'b28596baf87e25a078789f1c05817c8a3bf71257', 'versionType': 'git'}, {'status': 'affected', 'version': '45dac1d6ea045ae56e4df8d9c70c92c7412bd4fc', 'lessThan': '34a71f5361fc3adb5b7138da78750b0d535a8252', 'versionType': 'git'}], 'programFiles': ['drivers/net/vmxnet3/vmxnet3_drv.c'], 'defaultStatus': 'unaffected'}, {'repo': 'https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git', 'vendor': 'Linux', 'product': 'Linux', 'versions': [{'status': 'affected', 'version': '4.2'}, {'status': 'unaffected', 'version': '0', 'lessThan': '4.2', 'versionType': 'semver'}, {'status': 'unaffected', 'version': '6.6.148', 'versionType': 'semver', 'lessThanOrEqual': '6.6.*'}, {'status': 'unaffected', 'version': '6.12.101', 'versionType': 'semver', 'lessThanOrEqual': '6.12.*'}, {'status': 'unaffected', 'version': '6.18.42', 'versionType': 'semver', 'lessThanOrEqual': '6.18.*'}, {'status': 'unaffected', 'version': '7.1.6', 'versionType': 'semver', 'lessThanOrEqual': '7.1.*'}, {'status': 'unaffected', 'version': '7.2', 'versionType': 'original_commit_for_fix', 'lessThanOrEqual': '*'}], 'programFiles': ['drivers/net/vmxnet3/vmxnet3_drv.c'], 'defaultStatus': 'affected'}] -
CVE Modified by 416baaa9-dc9f-4396-8d5f-8c081fb06d67
Aug. 13, 2026
Action Type Old Value New Value Added CVSS V3.1 AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:H -
New CVE Received by 416baaa9-dc9f-4396-8d5f-8c081fb06d67
Aug. 10, 2026
Action Type Old Value New Value Added Affected [{'repo': 'https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git', 'vendor': 'Linux', 'product': 'Linux', 'versions': [{'status': 'affected', 'version': '45dac1d6ea045ae56e4df8d9c70c92c7412bd4fc', 'lessThan': '667b6e52048eaf4dbcf1707ed87ffd44abb9cb38', 'versionType': 'git'}, {'status': 'affected', 'version': '45dac1d6ea045ae56e4df8d9c70c92c7412bd4fc', 'lessThan': '28cb5d8d13b4c1faf3f688f62e5df82fe7b438d8', 'versionType': 'git'}, {'status': 'affected', 'version': '45dac1d6ea045ae56e4df8d9c70c92c7412bd4fc', 'lessThan': '4fdb0f162ccdbe9626863b10003855703253fa29', 'versionType': 'git'}, {'status': 'affected', 'version': '45dac1d6ea045ae56e4df8d9c70c92c7412bd4fc', 'lessThan': 'b28596baf87e25a078789f1c05817c8a3bf71257', 'versionType': 'git'}, {'status': 'affected', 'version': '45dac1d6ea045ae56e4df8d9c70c92c7412bd4fc', 'lessThan': '34a71f5361fc3adb5b7138da78750b0d535a8252', 'versionType': 'git'}], 'programFiles': ['drivers/net/vmxnet3/vmxnet3_drv.c'], 'defaultStatus': 'unaffected'}, {'repo': 'https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git', 'vendor': 'Linux', 'product': 'Linux', 'versions': [{'status': 'affected', 'version': '4.2'}, {'status': 'unaffected', 'version': '0', 'lessThan': '4.2', 'versionType': 'semver'}, {'status': 'unaffected', 'version': '6.6.148', 'versionType': 'semver', 'lessThanOrEqual': '6.6.*'}, {'status': 'unaffected', 'version': '6.12.101', 'versionType': 'semver', 'lessThanOrEqual': '6.12.*'}, {'status': 'unaffected', 'version': '6.18.42', 'versionType': 'semver', 'lessThanOrEqual': '6.18.*'}, {'status': 'unaffected', 'version': '7.1.6', 'versionType': 'semver', 'lessThanOrEqual': '7.1.*'}, {'status': 'unaffected', 'version': '7.2-rc5', 'versionType': 'original_commit_for_fix', 'lessThanOrEqual': '*'}], 'programFiles': ['drivers/net/vmxnet3/vmxnet3_drv.c'], 'defaultStatus': 'affected'}] Added Description 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. Added Reference https://git.kernel.org/stable/c/28cb5d8d13b4c1faf3f688f62e5df82fe7b438d8 Added Reference https://git.kernel.org/stable/c/34a71f5361fc3adb5b7138da78750b0d535a8252 Added Reference https://git.kernel.org/stable/c/4fdb0f162ccdbe9626863b10003855703253fa29 Added Reference https://git.kernel.org/stable/c/667b6e52048eaf4dbcf1707ed87ffd44abb9cb38 Added Reference https://git.kernel.org/stable/c/b28596baf87e25a078789f1c05817c8a3bf71257