Linux Kernel up to 6.18.41/7.1.5/7.2-rc3 iptfs iptfs_skb_add_frags memory corruption

CVSS Meta Temp Score
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Current Exploit Price (≈)
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CTI Interest Score
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9.6$5k-$25k0.00

Summaryinfo

A vulnerability has been found in Linux Kernel up to 6.18.41/7.1.5/7.2-rc3 and classified as very critical. Affected by this issue is the function iptfs_skb_add_frags of the component iptfs. The manipulation leads to memory corruption. This vulnerability is listed as CVE-2026-64566. The attack may be initiated remotely. There is no available exploit. The affected component should be upgraded.

Detailsinfo

A vulnerability was found in Linux Kernel up to 6.18.41/7.1.5/7.2-rc3 and classified as very critical. This issue affects the function iptfs_skb_add_frags of the component iptfs. The manipulation with an unknown input leads to a memory corruption vulnerability. Using CWE to declare the problem leads to CWE-119. The product performs operations on a memory buffer, but it can read from or write to a memory location that is outside of the intended boundary of the buffer. Impacted is confidentiality, integrity, and availability. The summary by CVE is:

In the Linux kernel, the following vulnerability has been resolved: xfrm: iptfs: propagate SKBFL_SHARED_FRAG in iptfs_skb_add_frags() When iptfs_skb_add_frags() copies frag references from the source frag walk into a new SKB, it increments the page reference count via __skb_frag_ref() but does not propagate SKBFL_SHARED_FRAG to the destination SKB's skb_shinfo->flags. If the source SKB carries shared frags (e.g. from a page-pool backed receive path), the new inner SKB will appear to ESP as having privately owned frags. A subsequent esp_input() call for a nested transport-mode SA then takes the no-COW fast path and decrypts in place, writing over pages that are still referenced by the outer IPTFS SKB. This causes kernel-visible memory corruption and can trigger a panic. All other frag-transfer helpers in the kernel (skb_try_coalesce, skb_gro_receive, __pskb_copy_fclone, skb_shift, skb_segment) correctly propagate SKBFL_SHARED_FRAG; align iptfs_skb_add_frags() with this convention by setting the flag inside the loop immediately after __skb_frag_ref() and nr_frags++, so every exit path that attaches a frag unconditionally propagates SKBFL_SHARED_FRAG.

It is possible to read the advisory at git.kernel.org. The identification of this vulnerability is CVE-2026-64566 since 07/19/2026. The exploitation is known to be easy. The attack may be initiated remotely. No form of authentication is needed for a successful exploitation. Technical details of the vulnerability are known, but there is no available exploit. The pricing for an exploit might be around USD $5k-$25k at the moment (estimation calculated on 08/19/2026).

Upgrading to version 6.18.42, 7.1.6 or 7.2-rc4 eliminates this vulnerability. Applying the patch d8aaf06b29f5a0b6186cf68d21c7d63678ee3891/ffd64e0717efd83fbf3396ab4e5ac6d795dac4d0/430ea57d6daf765e88f90046afbfd1e071cb7200 is able to eliminate this problem. The best possible mitigation is suggested to be upgrading to the latest version.

The vulnerability is also documented in the vulnerability database at CERT Bund (WID-SEC-2026-2659). Statistical analysis made it clear that VulDB provides the best quality for vulnerability data.

Affected

  • Debian Linux
  • SUSE openSUSE
  • Open Source Linux Kernel

Productinfo

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CPE 2.3info

CPE 2.2info

CVSSv4info

VulDB Vector: 🔒
VulDB Reliability: 🔍

CVSSv3info

VulDB Meta Base Score: 9.9
VulDB Meta Temp Score: 9.6

VulDB Base Score: 10.0
VulDB Temp Score: 9.5
VulDB Vector: 🔒
VulDB Reliability: 🔍

CNA Base Score: 9.8
CNA Vector (Linux): 🔒

CVSSv2info

AVACAuCIA
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VectorComplexityAuthenticationConfidentialityIntegrityAvailability
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VulDB Base Score: 🔒
VulDB Temp Score: 🔒
VulDB Reliability: 🔍

Exploitinginfo

Class: Memory corruption
CWE: CWE-119
CAPEC: 🔒
ATT&CK: 🔒

Physical: No
Local: No
Remote: Yes

Availability: 🔒
Status: Not defined

EPSS Score: 🔒
EPSS Percentile: 🔒

Price Prediction: 🔍
Current Price Estimation: 🔒

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Threat Intelligenceinfo

Interest: 🔍
Active Actors: 🔍
Active APT Groups: 🔍

Countermeasuresinfo

Recommended: Upgrade
Status: 🔍

0-Day Time: 🔒

Upgrade: Kernel 6.18.42/7.1.6/7.2-rc4
Patch: d8aaf06b29f5a0b6186cf68d21c7d63678ee3891/ffd64e0717efd83fbf3396ab4e5ac6d795dac4d0/430ea57d6daf765e88f90046afbfd1e071cb7200

Timelineinfo

07/19/2026 CVE reserved
08/05/2026 +17 days Advisory disclosed
08/05/2026 +0 days VulDB entry created
08/19/2026 +14 days VulDB entry last update

Sourcesinfo

Vendor: kernel.org

Advisory: git.kernel.org
Status: Confirmed

CVE: CVE-2026-64566 (🔒)
GCVE (CVE): GCVE-0-2026-64566
GCVE (VulDB): GCVE-100-386123
CERT Bund: WID-SEC-2026-2659 - Linux Kernel: Mehrere Schwachstellen

Entryinfo

Created: 08/05/2026 10:20
Updated: 08/19/2026 08:05
Changes: 08/05/2026 10:20 (59), 08/09/2026 21:53 (11), 08/19/2026 08:05 (7)
Complete: 🔍
Cache ID: 216::103

Statistical analysis made it clear that VulDB provides the best quality for vulnerability data.

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