Vulnerability-Lookup

FKIE_CVE-2026-31684

Vulnerability from fkie_nvd - Published: 2026-04-25 09:16 - Updated: 2026-05-06 21:11

Severity ?

5.5 (Medium) - CVSS:3.1/AV:L/AC:L/PR:L/UI:N/S:U/C:N/I:N/A:H

Summary

In the Linux kernel, the following vulnerability has been resolved: net: sched: act_csum: validate nested VLAN headers tcf_csum_act() walks nested VLAN headers directly from skb->data when an skb still carries in-payload VLAN tags. The current code reads vlan->h_vlan_encapsulated_proto and then pulls VLAN_HLEN bytes without first ensuring that the full VLAN header is present in the linear area. If only part of an inner VLAN header is linearized, accessing h_vlan_encapsulated_proto reads past the linear area, and the following skb_pull(VLAN_HLEN) may violate skb invariants. Fix this by requiring pskb_may_pull(skb, VLAN_HLEN) before accessing and pulling each nested VLAN header. If the header still is not fully available, drop the packet through the existing error path.

References

URL	Tags
416baaa9-dc9f-4396-8d5f-8c081fb06d67	https://git.kernel.org/stable/c/3d165d975305cf76ff0b10a3c798fb31e5f5f9a5	Patch
416baaa9-dc9f-4396-8d5f-8c081fb06d67	https://git.kernel.org/stable/c/a69738efea0996d05a3c7d2178551b891744df1b	Patch
416baaa9-dc9f-4396-8d5f-8c081fb06d67	https://git.kernel.org/stable/c/c842743d073bdd683606cb414eb0ca84465dd834	Patch
416baaa9-dc9f-4396-8d5f-8c081fb06d67	https://git.kernel.org/stable/c/eb3765b90eb8f2a3d6310a80c14a9e57ec4267a2	Patch
416baaa9-dc9f-4396-8d5f-8c081fb06d67	https://git.kernel.org/stable/c/ec4930979b3f7bbeb7af5744599fc6603a4dba62	Patch

Impacted products

Vendor	Product	Version
linux	linux_kernel	*
linux	linux_kernel	*
linux	linux_kernel	*
linux	linux_kernel	*
linux	linux_kernel	*
linux	linux_kernel	7.0
linux	linux_kernel	7.0
linux	linux_kernel	7.0
linux	linux_kernel	7.0
linux	linux_kernel	7.0
linux	linux_kernel	7.0
linux	linux_kernel	7.0

JSON

To clipboard

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    }
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  "id": "CVE-2026-31684",
  "lastModified": "2026-05-06T21:11:34.630",
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          "baseScore": 5.5,
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          "confidentialityImpact": "NONE",
          "integrityImpact": "NONE",
          "privilegesRequired": "LOW",
          "scope": "UNCHANGED",
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CVE-2026-31684 (GCVE-0-2026-31684)

Vulnerability from cvelistv5 – Published: 2026-04-25 08:47 – Updated: 2026-04-27 13:57

Title

net: sched: act_csum: validate nested VLAN headers

Summary

Severity ?

No CVSS data available.

Assigner

Linux

References

URL

Tags

	https://git.kernel.org/stable/c/eb3765b90eb8f2a3d…
	https://git.kernel.org/stable/c/a69738efea0996d05…
	https://git.kernel.org/stable/c/ec4930979b3f7bbeb…
	https://git.kernel.org/stable/c/3d165d975305cf76f…
	https://git.kernel.org/stable/c/c842743d073bdd683…

Impacted products

Vendor

Product

Version

Linux

Affected: 2ecba2d1e45b24620a7c3df9531895cf68d5dec6 , < eb3765b90eb8f2a3d6310a80c14a9e57ec4267a2 (git)
Affected: 2ecba2d1e45b24620a7c3df9531895cf68d5dec6 , < a69738efea0996d05a3c7d2178551b891744df1b (git)
Affected: 2ecba2d1e45b24620a7c3df9531895cf68d5dec6 , < ec4930979b3f7bbeb7af5744599fc6603a4dba62 (git)
Affected: 2ecba2d1e45b24620a7c3df9531895cf68d5dec6 , < 3d165d975305cf76ff0b10a3c798fb31e5f5f9a5 (git)
Affected: 2ecba2d1e45b24620a7c3df9531895cf68d5dec6 , < c842743d073bdd683606cb414eb0ca84465dd834 (git)
Affected: 3764bfae5056e95617b6ee074129297e11710886 (git)

Linux

Affected: 5.1
Unaffected: 0 , < 5.1 (semver)
Unaffected: 6.6.136 , ≤ 6.6.* (semver)
Unaffected: 6.12.83 , ≤ 6.12.* (semver)
Unaffected: 6.18.24 , ≤ 6.18.* (semver)
Unaffected: 6.19.14 , ≤ 6.19.* (semver)
Unaffected: 7.0 , ≤ * (original_commit_for_fix)

Show details on NVD website

JSON

To clipboard

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Sightings

Author	Source	Type	Date	Other

Nomenclature

Seen: The vulnerability was mentioned, discussed, or observed by the user.
Confirmed: The vulnerability has been validated from an analyst's perspective.
Published Proof of Concept: A public proof of concept is available for this vulnerability.
Exploited: The vulnerability was observed as exploited by the user who reported the sighting.
Patched: The vulnerability was observed as successfully patched by the user who reported the sighting.
Not exploited: The vulnerability was not observed as exploited by the user who reported the sighting.
Not confirmed: The user expressed doubt about the validity of the vulnerability.
Not patched: The vulnerability was not observed as successfully patched by the user who reported the sighting.

Detection rules are retrieved from Rulezet.

Action not permitted

FKIE_CVE-2026-31684

CVE-2026-31684 (GCVE-0-2026-31684)

Tags

Sightings

Nomenclature