CVE-2026-64207
net/sched: dualpi2: fix GSO backlog accounting
Description
In the Linux kernel, the following vulnerability has been resolved: net/sched: dualpi2: fix GSO backlog accounting When DualPI2 splits a GSO skb into N segments, it propagates N additional packets to its parent before returning NET_XMIT_SUCCESS. The parent then accounts for the original skb once more, leaving its qlen one larger than the number of packets actually queued. With QFQ as the parent, after all real packets are dequeued, QFQ still has a non-zero qlen while its in-service aggregate has no active classes. qfq_choose_next_agg() returns NULL and qfq_dequeue() passes the result to qfq_peek_skb(), causing a NULL pointer dereference. Follow the same pattern used by tbf_segment() and taprio: count only successfully queued segments, propagate the difference between the original skb and those segments, and return NET_XMIT_SUCCESS whenever at least one segment was queued.
INFO
Published Date :
July 20, 2026, 5:18 p.m.
Last Modified :
Aug. 17, 2026, 5:17 a.m.
Remotely Exploit :
No
Source :
416baaa9-dc9f-4396-8d5f-8c081fb06d67
CVSS Scores
| Score | Version | Severity | Vector | Exploitability Score | Impact Score | Source |
|---|---|---|---|---|---|---|
| CVSS 3.1 | MEDIUM | [email protected] |
Solution
- Ensure GSO segments are accounted for correctly.
- Propagate differences between original skb and segments.
- Return NET_XMIT_SUCCESS when segments are queued.
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-2026-64207.
CWE - Common Weakness Enumeration
While CVE identifies
specific instances of vulnerabilities, CWE categorizes the common flaws or
weaknesses that can lead to vulnerabilities. CVE-2026-64207 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-2026-64207
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-2026-64207 vulnerability anywhere in the article.
The following table lists the changes that have been made to the
CVE-2026-64207 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': '8f9516daedd67097a0c6e463fcb7a42b5ee9d477', 'lessThan': 'c4b70c1512b8f9f33f23c2c8196dfd1210207681', 'versionType': 'git'}, {'status': 'affected', 'version': '8f9516daedd67097a0c6e463fcb7a42b5ee9d477', 'lessThan': '806586e33891066487db1f002be3d455cda6b516', 'versionType': 'git'}, {'status': 'affected', 'version': '8f9516daedd67097a0c6e463fcb7a42b5ee9d477', 'lessThan': '05ed733b65ab977dd931e7f7ac0f62fdb81205c2', 'versionType': 'git'}], 'programFiles': ['net/sched/sch_dualpi2.c'], 'defaultStatus': 'unaffected'}, {'repo': 'https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git', 'vendor': 'Linux', 'product': 'Linux', 'versions': [{'status': 'affected', 'version': '6.17'}, {'status': 'unaffected', 'version': '0', 'lessThan': '6.17', 'versionType': 'semver'}, {'status': 'unaffected', 'version': '6.18.39', 'versionType': 'semver', 'lessThanOrEqual': '6.18.*'}, {'status': 'unaffected', 'version': '7.1.4', 'versionType': 'semver', 'lessThanOrEqual': '7.1.*'}, {'status': 'unaffected', 'version': '7.2-rc1', 'versionType': 'original_commit_for_fix', 'lessThanOrEqual': '*'}], 'programFiles': ['net/sched/sch_dualpi2.c'], 'defaultStatus': 'affected'}] [{'repo': 'https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git', 'vendor': 'Linux', 'product': 'Linux', 'versions': [{'status': 'affected', 'version': '8f9516daedd67097a0c6e463fcb7a42b5ee9d477', 'lessThan': 'c4b70c1512b8f9f33f23c2c8196dfd1210207681', 'versionType': 'git'}, {'status': 'affected', 'version': '8f9516daedd67097a0c6e463fcb7a42b5ee9d477', 'lessThan': '806586e33891066487db1f002be3d455cda6b516', 'versionType': 'git'}, {'status': 'affected', 'version': '8f9516daedd67097a0c6e463fcb7a42b5ee9d477', 'lessThan': '05ed733b65ab977dd931e7f7ac0f62fdb81205c2', 'versionType': 'git'}], 'programFiles': ['net/sched/sch_dualpi2.c'], 'defaultStatus': 'unaffected'}, {'repo': 'https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git', 'vendor': 'Linux', 'product': 'Linux', 'versions': [{'status': 'affected', 'version': '6.17'}, {'status': 'unaffected', 'version': '0', 'lessThan': '6.17', 'versionType': 'semver'}, {'status': 'unaffected', 'version': '6.18.39', 'versionType': 'semver', 'lessThanOrEqual': '6.18.*'}, {'status': 'unaffected', 'version': '7.1.4', 'versionType': 'semver', 'lessThanOrEqual': '7.1.*'}, {'status': 'unaffected', 'version': '7.2', 'versionType': 'original_commit_for_fix', 'lessThanOrEqual': '*'}], 'programFiles': ['net/sched/sch_dualpi2.c'], 'defaultStatus': 'affected'}] -
Initial Analysis by [email protected]
Aug. 11, 2026
Action Type Old Value New Value Added CVSS V3.1 AV:L/AC:L/PR:L/UI:N/S:U/C:N/I:N/A:H Added CWE CWE-476 Added CPE Configuration OR *cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:* versions from (including) 6.19 up to (excluding) 7.1.4 *cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:* versions from (including) 6.17 up to (excluding) 6.18.39 Added Reference Type kernel.org: https://git.kernel.org/stable/c/05ed733b65ab977dd931e7f7ac0f62fdb81205c2 Types: Patch Added Reference Type kernel.org: https://git.kernel.org/stable/c/806586e33891066487db1f002be3d455cda6b516 Types: Patch Added Reference Type kernel.org: https://git.kernel.org/stable/c/c4b70c1512b8f9f33f23c2c8196dfd1210207681 Types: Patch -
New CVE Received by 416baaa9-dc9f-4396-8d5f-8c081fb06d67
Jul. 20, 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': '8f9516daedd67097a0c6e463fcb7a42b5ee9d477', 'lessThan': 'c4b70c1512b8f9f33f23c2c8196dfd1210207681', 'versionType': 'git'}, {'status': 'affected', 'version': '8f9516daedd67097a0c6e463fcb7a42b5ee9d477', 'lessThan': '806586e33891066487db1f002be3d455cda6b516', 'versionType': 'git'}, {'status': 'affected', 'version': '8f9516daedd67097a0c6e463fcb7a42b5ee9d477', 'lessThan': '05ed733b65ab977dd931e7f7ac0f62fdb81205c2', 'versionType': 'git'}], 'programFiles': ['net/sched/sch_dualpi2.c'], 'defaultStatus': 'unaffected'}, {'repo': 'https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git', 'vendor': 'Linux', 'product': 'Linux', 'versions': [{'status': 'affected', 'version': '6.17'}, {'status': 'unaffected', 'version': '0', 'lessThan': '6.17', 'versionType': 'semver'}, {'status': 'unaffected', 'version': '6.18.39', 'versionType': 'semver', 'lessThanOrEqual': '6.18.*'}, {'status': 'unaffected', 'version': '7.1.4', 'versionType': 'semver', 'lessThanOrEqual': '7.1.*'}, {'status': 'unaffected', 'version': '7.2-rc1', 'versionType': 'original_commit_for_fix', 'lessThanOrEqual': '*'}], 'programFiles': ['net/sched/sch_dualpi2.c'], 'defaultStatus': 'affected'}] Added Description In the Linux kernel, the following vulnerability has been resolved: net/sched: dualpi2: fix GSO backlog accounting When DualPI2 splits a GSO skb into N segments, it propagates N additional packets to its parent before returning NET_XMIT_SUCCESS. The parent then accounts for the original skb once more, leaving its qlen one larger than the number of packets actually queued. With QFQ as the parent, after all real packets are dequeued, QFQ still has a non-zero qlen while its in-service aggregate has no active classes. qfq_choose_next_agg() returns NULL and qfq_dequeue() passes the result to qfq_peek_skb(), causing a NULL pointer dereference. Follow the same pattern used by tbf_segment() and taprio: count only successfully queued segments, propagate the difference between the original skb and those segments, and return NET_XMIT_SUCCESS whenever at least one segment was queued. Added Reference https://git.kernel.org/stable/c/05ed733b65ab977dd931e7f7ac0f62fdb81205c2 Added Reference https://git.kernel.org/stable/c/806586e33891066487db1f002be3d455cda6b516 Added Reference https://git.kernel.org/stable/c/c4b70c1512b8f9f33f23c2c8196dfd1210207681