CVE-2026-64530
net/sched: cls_api: Handle TC_ACT_CONSUMED in tcf_qevent_handle
Description
In the Linux kernel, the following vulnerability has been resolved: net/sched: cls_api: Handle TC_ACT_CONSUMED in tcf_qevent_handle tcf_classify() can return TC_ACT_CONSUMED while the skb is held by the defragmentation engine (e.g. act_ct on out-of-order fragments). When that happens the skb is no longer owned by the caller and must not be touched again. tcf_qevent_handle() did not handle TC_ACT_CONSUMED: it fell through the switch and returned the skb to the caller as if classification had passed. The only qdisc that wires up qevents today is RED, via three call sites (qe_mark on RED_PROB_MARK/HARD_MARK, qe_early_drop on congestion_drop) red_enqueue() was continuing to operate on an skb it no longer owns in this case -- enqueueing it, dropping it, or updating statistics. Resulting in a UAF. tc qdisc add dev eth0 root handle 1: red ... qevent early_drop block 10 tc filter add block 10 ... action ct (with ct defrag enabled and traffic that produces out-of-order fragments, e.g. a fragmented UDP stream) Handle TC_ACT_CONSUMED in tcf_qevent_handle() the same way the ingress and egress fast paths do: treat it as stolen and return NULL without touching the skb. Unlike the TC_ACT_STOLEN case, the skb must not be dropped/freed here, as it is no longer owned by us.
INFO
Published Date :
July 26, 2026, 7:16 a.m.
Last Modified :
July 26, 2026, 7:16 a.m.
Remotely Exploit :
No
Source :
416baaa9-dc9f-4396-8d5f-8c081fb06d67
Affected Products
The following products are affected by CVE-2026-64530
vulnerability.
Even if cvefeed.io is aware of the exact versions of the
products
that
are
affected, the information is not represented in the table below.
No affected product recoded yet
Solution
- Update the Linux kernel to resolve the vulnerability.
- Ensure TC_ACT_CONSUMED is handled as stolen.
- Do not touch the skb when it is no longer owned.
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-2026-64530.
CWE - Common Weakness Enumeration
While CVE identifies
specific instances of vulnerabilities, CWE categorizes the common flaws or
weaknesses that can lead to vulnerabilities. CVE-2026-64530 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-2026-64530
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-2026-64530 vulnerability anywhere in the article.
The following table lists the changes that have been made to the
CVE-2026-64530 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.
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New CVE Received by 416baaa9-dc9f-4396-8d5f-8c081fb06d67
Jul. 26, 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': '172ba7d46c202e679f3ccb10264c67416aaeb1c4', 'lessThan': '5ed3d6f85991656667059d3fa5a1d683ac58c447', 'versionType': 'git'}, {'status': 'affected', 'version': '0b5b831122fc3789fff75be433ba3e4dd7b779d4', 'lessThan': 'f42e8134a3a1074b834a574d404352f867ba994a', 'versionType': 'git'}, {'status': 'affected', 'version': '73f7da5fd124f2cda9161e2e46114915e6e82e97', 'lessThan': '447d493034a9cf7bf13a2abac86d0573d907ec2f', 'versionType': 'git'}, {'status': 'affected', 'version': '3f14b377d01d8357eba032b4cabc8c1149b458b6', 'lessThan': 'e1270e69dcf2c3512c453484178f2e9dc0db3f05', 'versionType': 'git'}, {'status': 'affected', 'version': '3f14b377d01d8357eba032b4cabc8c1149b458b6', 'lessThan': '2140c2f3f2e7b066e1ae616ede8856cafd8015e9', 'versionType': 'git'}, {'status': 'affected', 'version': '3f14b377d01d8357eba032b4cabc8c1149b458b6', 'lessThan': 'e28aedab9488343924d227b5a896faed67ce84d5', 'versionType': 'git'}, {'status': 'affected', 'version': '3f14b377d01d8357eba032b4cabc8c1149b458b6', 'lessThan': 'a8a02897f2b479127db261de05cbf0c28b98d159', 'versionType': 'git'}, {'status': 'affected', 'version': 'f5346df0591d10bc948761ca854b1fae6d2ef441', 'versionType': 'git'}, {'status': 'affected', 'version': '5.15.148', 'lessThan': '5.15.212', 'versionType': 'semver'}, {'status': 'affected', 'version': '6.1.75', 'lessThan': '6.1.178', 'versionType': 'semver'}, {'status': 'affected', 'version': '6.6.14', 'lessThan': '6.6.145', 'versionType': 'semver'}, {'status': 'affected', 'version': '6.7.2', 'lessThan': '6.8', 'versionType': 'semver'}], 'programFiles': ['net/sched/cls_api.c'], 'defaultStatus': 'unaffected'}, {'repo': 'https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git', 'vendor': 'Linux', 'product': 'Linux', 'versions': [{'status': 'affected', 'version': '6.8'}, {'status': 'unaffected', 'version': '0', 'lessThan': '6.8', 'versionType': 'semver'}, {'status': 'unaffected', 'version': '5.15.212', 'versionType': 'semver', 'lessThanOrEqual': '5.15.*'}, {'status': 'unaffected', 'version': '6.1.178', 'versionType': 'semver', 'lessThanOrEqual': '6.1.*'}, {'status': 'unaffected', 'version': '6.6.145', 'versionType': 'semver', 'lessThanOrEqual': '6.6.*'}, {'status': 'unaffected', 'version': '6.12.97', 'versionType': 'semver', 'lessThanOrEqual': '6.12.*'}, {'status': 'unaffected', 'version': '6.18.40', 'versionType': 'semver', 'lessThanOrEqual': '6.18.*'}, {'status': 'unaffected', 'version': '7.1.5', 'versionType': 'semver', 'lessThanOrEqual': '7.1.*'}, {'status': 'unaffected', 'version': '7.2-rc1', 'versionType': 'original_commit_for_fix', 'lessThanOrEqual': '*'}], 'programFiles': ['net/sched/cls_api.c'], 'defaultStatus': 'affected'}] Added Description In the Linux kernel, the following vulnerability has been resolved: net/sched: cls_api: Handle TC_ACT_CONSUMED in tcf_qevent_handle tcf_classify() can return TC_ACT_CONSUMED while the skb is held by the defragmentation engine (e.g. act_ct on out-of-order fragments). When that happens the skb is no longer owned by the caller and must not be touched again. tcf_qevent_handle() did not handle TC_ACT_CONSUMED: it fell through the switch and returned the skb to the caller as if classification had passed. The only qdisc that wires up qevents today is RED, via three call sites (qe_mark on RED_PROB_MARK/HARD_MARK, qe_early_drop on congestion_drop) red_enqueue() was continuing to operate on an skb it no longer owns in this case -- enqueueing it, dropping it, or updating statistics. Resulting in a UAF. tc qdisc add dev eth0 root handle 1: red ... qevent early_drop block 10 tc filter add block 10 ... action ct (with ct defrag enabled and traffic that produces out-of-order fragments, e.g. a fragmented UDP stream) Handle TC_ACT_CONSUMED in tcf_qevent_handle() the same way the ingress and egress fast paths do: treat it as stolen and return NULL without touching the skb. Unlike the TC_ACT_STOLEN case, the skb must not be dropped/freed here, as it is no longer owned by us. Added Reference https://git.kernel.org/stable/c/2140c2f3f2e7b066e1ae616ede8856cafd8015e9 Added Reference https://git.kernel.org/stable/c/447d493034a9cf7bf13a2abac86d0573d907ec2f Added Reference https://git.kernel.org/stable/c/5ed3d6f85991656667059d3fa5a1d683ac58c447 Added Reference https://git.kernel.org/stable/c/a8a02897f2b479127db261de05cbf0c28b98d159 Added Reference https://git.kernel.org/stable/c/e1270e69dcf2c3512c453484178f2e9dc0db3f05 Added Reference https://git.kernel.org/stable/c/e28aedab9488343924d227b5a896faed67ce84d5 Added Reference https://git.kernel.org/stable/c/f42e8134a3a1074b834a574d404352f867ba994a