Linux Kernel up to 6.17.2 bpf_sock_addr privilege escalation

CVSS Meta Temp Score
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CTI Interest Score
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5.3$0-$5k0.00

Summaryinfo

A vulnerability, which was classified as critical, has been found in Linux Kernel up to 5.15.194/6.1.155/6.6.111/6.12.52/6.17.2. Affected by this vulnerability is the function bpf_sock_addr. The manipulation leads to an unknown weakness. This vulnerability is referenced as CVE-2025-40078. No exploit is available. It is advisable to upgrade the affected component.

Detailsinfo

A vulnerability, which was classified as critical, has been found in Linux Kernel up to 5.15.194/6.1.155/6.6.111/6.12.52/6.17.2. The impact remains unknown. The summary by CVE is:

In the Linux kernel, the following vulnerability has been resolved: bpf: Explicitly check accesses to bpf_sock_addr Syzkaller found a kernel warning on the following sock_addr program: 0: r0 = 0 1: r2 = *(u32 *)(r1 +60) 2: exit which triggers: verifier bug: error during ctx access conversion (0) This is happening because offset 60 in bpf_sock_addr corresponds to an implicit padding of 4 bytes, right after msg_src_ip4. Access to this padding isn't rejected in sock_addr_is_valid_access and it thus later fails to convert the access. This patch fixes it by explicitly checking the various fields of bpf_sock_addr in sock_addr_is_valid_access. I checked the other ctx structures and is_valid_access functions and didn't find any other similar cases. Other cases of (properly handled) padding are covered in new tests in a subsequent patch.

It is possible to read the advisory at git.kernel.org. The identification of this vulnerability is CVE-2025-40078 since 04/16/2025. Technical details of the vulnerability are known, but there is no available exploit. The pricing for an exploit might be around USD $0-$5k at the moment (estimation calculated on 02/15/2026).

The vulnerability scanner Nessus provides a plugin with the ID 271870 (Linux Distros Unpatched Vulnerability : CVE-2025-40078), which helps to determine the existence of the flaw in a target environment.

Upgrading to version 5.15.195, 6.1.156, 6.6.112, 6.12.53, 6.17.3 or 6.18-rc1 eliminates this vulnerability. Applying the patch 6d8b1a21fd5c34622b0c3893c61e4a38d8ba53ec/4f00858cd9bbbdf67159e28b85a8ca9e77c83622/cdeafacb4f9ff261a96baef519e29480fd7b1019/fe9d33f0470350558cb08cecb54cf2267b3a45d2/ad8b4fe5617e3c85fc23267f02500c4f3bf0ff69/6fabca2fc94d33cdf7ec102058983b086293395f is able to eliminate this problem. The bugfix is ready for download at git.kernel.org. The best possible mitigation is suggested to be upgrading to the latest version.

The vulnerability is also documented in the databases at Tenable (271870) and CERT Bund (WID-SEC-2025-2431). Statistical analysis made it clear that VulDB provides the best quality for vulnerability data.

Affected

  • Google Container-Optimized OS
  • Debian Linux
  • Amazon Linux 2
  • Red Hat Enterprise Linux
  • Ubuntu Linux
  • SUSE Linux
  • Oracle Linux
  • SUSE openSUSE
  • Open Source Linux Kernel
  • RESF Rocky Linux
  • Microsoft Azure
  • Dell NetWorker

Productinfo

Type

Vendor

Name

Version

License

Website

CPE 2.3info

CPE 2.2info

CVSSv4info

VulDB Vector: 🔒
VulDB Reliability: 🔍

CVSSv3info

VulDB Meta Base Score: 5.5
VulDB Meta Temp Score: 5.3

VulDB Base Score: 5.5
VulDB Temp Score: 5.3
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: Privilege escalation
CWE: Unknown
CAPEC: 🔒
ATT&CK: 🔒

Physical: No
Local: No
Remote: Partially

Availability: 🔒
Status: Not defined

EPSS Score: 🔒
EPSS Percentile: 🔒

Price Prediction: 🔍
Current Price Estimation: 🔒

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Nessus ID: 271870
Nessus Name: Linux Distros Unpatched Vulnerability : CVE-2025-40078

Threat Intelligenceinfo

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

Countermeasuresinfo

Recommended: Upgrade
Status: 🔍

0-Day Time: 🔒

Upgrade: Kernel 5.15.195/6.1.156/6.6.112/6.12.53/6.17.3/6.18-rc1
Patch: 6d8b1a21fd5c34622b0c3893c61e4a38d8ba53ec/4f00858cd9bbbdf67159e28b85a8ca9e77c83622/cdeafacb4f9ff261a96baef519e29480fd7b1019/fe9d33f0470350558cb08cecb54cf2267b3a45d2/ad8b4fe5617e3c85fc23267f02500c4f3bf0ff69/6fabca2fc94d33cdf7ec102058983b086293395f

Timelineinfo

04/16/2025 CVE reserved
10/28/2025 +195 days Advisory disclosed
10/28/2025 +0 days VulDB entry created
02/15/2026 +110 days VulDB entry last update

Sourcesinfo

Vendor: kernel.org

Advisory: git.kernel.org
Status: Confirmed

CVE: CVE-2025-40078 (🔒)
GCVE (CVE): GCVE-0-2025-40078
GCVE (VulDB): GCVE-100-330275
CERT Bund: WID-SEC-2025-2431 - Linux Kernel: Mehrere Schwachstellen

Entryinfo

Created: 10/28/2025 15:51
Updated: 02/15/2026 23:08
Changes: 10/28/2025 15:51 (57), 10/30/2025 07:49 (7), 10/30/2025 14:45 (2), 11/25/2025 02:03 (1), 12/22/2025 02:00 (1), 02/08/2026 18:58 (1), 02/15/2026 23:08 (1)
Complete: 🔍
Cache ID: 216::103

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

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