CVE-2026-74290
net/sched: cls_flow: Dont expose folded kernel pointers
Description
In the Linux kernel, the following vulnerability has been resolved: net/sched: cls_flow: Dont expose folded kernel pointers The flow classifier falls back to addr_fold() for fields that are missing from packet headers. In map mode, userspace controls mask, xor, rshift, addend and divisor, and can observe the resulting classid through class statistics. This allows a tc classifier in a user/network namespace to recover the 32-bit folded value of skb->sk, skb_dst() or skb_nfct(). Align with standard kernel practices for pointer hashing and replace the XOR folding with a keyed siphash (which is cryptographically secure)
INFO
Published Date :
Aug. 15, 2026, 6:22 a.m.
Last Modified :
Aug. 15, 2026, 6:22 a.m.
Remotely Exploit :
No
Source :
416baaa9-dc9f-4396-8d5f-8c081fb06d67
Affected Products
The following products are affected by CVE-2026-74290
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 a version where the vulnerability is resolved.
- Replace XOR folding with keyed siphash for pointer hashing.
- Ensure secure handling of packet header fields.
- Validate user-controlled mask, xor, rshift, addend, and divisor.
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-2026-74290.
CWE - Common Weakness Enumeration
While CVE identifies
specific instances of vulnerabilities, CWE categorizes the common flaws or
weaknesses that can lead to vulnerabilities. CVE-2026-74290 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-2026-74290
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-2026-74290 vulnerability anywhere in the article.
The following table lists the changes that have been made to the
CVE-2026-74290 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
Aug. 15, 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': 'e5dfb815181fcb186d6080ac3a091eadff2d98fe', 'lessThan': '19f2ecf8ea564562c7e7a919cf38068dd9aa1c96', 'versionType': 'git'}, {'status': 'affected', 'version': 'e5dfb815181fcb186d6080ac3a091eadff2d98fe', 'lessThan': '3d054001860270748405a3f9270c5fa0bf7ffc19', 'versionType': 'git'}, {'status': 'affected', 'version': 'e5dfb815181fcb186d6080ac3a091eadff2d98fe', 'lessThan': 'fb31fbe51c233f3bf47021121f63d2e42cac2d08', 'versionType': 'git'}, {'status': 'affected', 'version': 'e5dfb815181fcb186d6080ac3a091eadff2d98fe', 'lessThan': '0a8b5b74f0e6b6b9ce453bcfa4baa502c4c7577a', 'versionType': 'git'}, {'status': 'affected', 'version': 'e5dfb815181fcb186d6080ac3a091eadff2d98fe', 'lessThan': '6151159618198675e01c391676e579738286c135', 'versionType': 'git'}, {'status': 'affected', 'version': 'e5dfb815181fcb186d6080ac3a091eadff2d98fe', 'lessThan': 'f294fc71c4a0fa4964f6428a1b4e7929c1d83125', 'versionType': 'git'}], 'programFiles': ['net/sched/cls_flow.c'], 'defaultStatus': 'unaffected'}, {'repo': 'https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git', 'vendor': 'Linux', 'product': 'Linux', 'versions': [{'status': 'affected', 'version': '2.6.25'}, {'status': 'unaffected', 'version': '0', 'lessThan': '2.6.25', 'versionType': 'semver'}, {'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_flow.c'], 'defaultStatus': 'affected'}] Added Description In the Linux kernel, the following vulnerability has been resolved: net/sched: cls_flow: Dont expose folded kernel pointers The flow classifier falls back to addr_fold() for fields that are missing from packet headers. In map mode, userspace controls mask, xor, rshift, addend and divisor, and can observe the resulting classid through class statistics. This allows a tc classifier in a user/network namespace to recover the 32-bit folded value of skb->sk, skb_dst() or skb_nfct(). Align with standard kernel practices for pointer hashing and replace the XOR folding with a keyed siphash (which is cryptographically secure) Added Reference https://git.kernel.org/stable/c/0a8b5b74f0e6b6b9ce453bcfa4baa502c4c7577a Added Reference https://git.kernel.org/stable/c/19f2ecf8ea564562c7e7a919cf38068dd9aa1c96 Added Reference https://git.kernel.org/stable/c/3d054001860270748405a3f9270c5fa0bf7ffc19 Added Reference https://git.kernel.org/stable/c/6151159618198675e01c391676e579738286c135 Added Reference https://git.kernel.org/stable/c/f294fc71c4a0fa4964f6428a1b4e7929c1d83125 Added Reference https://git.kernel.org/stable/c/fb31fbe51c233f3bf47021121f63d2e42cac2d08