Linux Kernel up to 6.6.144/6.12.96/6.18.39/7.1.4 SUNRPC xdr_buf_to_bvec out-of-bounds

CVSS Meta Temp Score
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CTI Interest Score
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9.5$0-$5k0.94

Summaryinfo

A vulnerability was found in Linux Kernel up to 6.6.144/6.12.96/6.18.39/7.1.4 and classified as very critical. Affected by this vulnerability is the function xdr_buf_to_bvec of the component SUNRPC. Such manipulation leads to out-of-bounds. This vulnerability is uniquely identified as CVE-2026-72217. The attack can be launched remotely. No exploit exists.

Detailsinfo

A vulnerability was found in Linux Kernel up to 6.6.144/6.12.96/6.18.39/7.1.4 and classified as very critical. Affected by this issue is the function xdr_buf_to_bvec of the component SUNRPC. The manipulation with an unknown input leads to a out-of-bounds vulnerability. Using CWE to declare the problem leads to CWE-125. The product reads data past the end, or before the beginning, of the intended buffer. Impacted is confidentiality, integrity, and availability. CVE summarizes:

In the Linux kernel, the following vulnerability has been resolved: SUNRPC: Bound-check xdr_buf_to_bvec() stores before writing xdr_buf_to_bvec() writes a bio_vec into the caller's array before testing whether that slot is in range, and the head branch performs the store with no check at all. When the caller's budget is exactly used up, the next store lands one element past the end of the array. The overflow label returns count - 1, which masks the surplus store but cannot undo it. rq_bvec, the array passed by nfsd_vfs_write(), is allocated to exactly rq_maxpages entries with no slack. The OOB store can land in adjacent slab memory; the bv_len and bv_offset fields written there are derived from client-supplied RPC payload sizes. Move the in-range check ahead of the store in the head, page-loop, and tail branches. With the check at the top of each sequence, count is incremented only after a successful store, so the overflow label can return count directly.

The advisory is shared for download at git.kernel.org. This vulnerability is handled as CVE-2026-72217 since 08/09/2026. The exploitation is known to be easy. The attack may be launched remotely. There are known technical details, but no exploit is available. The current price for an exploit might be approx. USD $0-$5k (estimation calculated on 08/15/2026).

Upgrading to version 6.6.145, 6.12.97, 6.18.40, 7.1.5 or 7.2-rc1 eliminates this vulnerability. Applying the patch 4a1148f2739d5089c3ca8ae2e9d1053e219ab5df/6029e711a818bf34d6c4b90cafee24f3afffa110/69e18135e2a004a79505451dbef07314ea16e1eb/98414b42530af65cb984ffc12685096a3b5e179a/42f5b80dda6b86e424054baf1475df686c403d5c is able to eliminate this problem.

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Productinfo

Type

Vendor

Name

Version

License

Website

CPE 2.3info

CPE 2.2info

CVSSv4info

VulDB Vector: 🔒
VulDB Reliability: 🔍

CVSSv3info

VulDB Meta Base Score: 9.9
VulDB Meta Temp Score: 9.5

VulDB Base Score: 9.9
VulDB Temp Score: 9.5
VulDB Vector: 🔒
VulDB Reliability: 🔍

CVSSv2info

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

Exploitinginfo

Class: Out-of-bounds
CWE: CWE-125 / CWE-119
CAPEC: 🔒
ATT&CK: 🔒

Physical: No
Local: No
Remote: Yes

Availability: 🔒
Status: Not defined
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 6.6.145/6.12.97/6.18.40/7.1.5/7.2-rc1
Patch: 4a1148f2739d5089c3ca8ae2e9d1053e219ab5df/6029e711a818bf34d6c4b90cafee24f3afffa110/69e18135e2a004a79505451dbef07314ea16e1eb/98414b42530af65cb984ffc12685096a3b5e179a/42f5b80dda6b86e424054baf1475df686c403d5c

Timelineinfo

08/09/2026 CVE reserved
08/15/2026 +6 days Advisory disclosed
08/15/2026 +0 days VulDB entry created
08/15/2026 +0 days VulDB entry last update

Sourcesinfo

Vendor: kernel.org

Advisory: git.kernel.org
Status: Confirmed

CVE: CVE-2026-72217 (🔒)
GCVE (CVE): GCVE-0-2026-72217
GCVE (VulDB): GCVE-100-390632

Entryinfo

Created: 08/15/2026 13:30
Changes: 08/15/2026 13:30 (59)
Complete: 🔍
Cache ID: 216::103

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