Linux Kernel up to 6.17-rc2 recvmsg buffer overflow

CVSS Meta Temp Score
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CTI Interest Score
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7.4$0-$5k0.00

Summaryinfo

A vulnerability marked as critical has been reported in Linux Kernel up to 6.1.148/6.6.102/6.12.43/6.16.3/6.17-rc2. Affected is the function recvmsg. Performing a manipulation results in buffer overflow. This vulnerability was named CVE-2025-39682. There is no available exploit. It is suggested to upgrade the affected component.

Detailsinfo

A vulnerability classified as critical has been found in Linux Kernel up to 6.1.148/6.6.102/6.12.43/6.16.3/6.17-rc2. This affects the function recvmsg. The manipulation with an unknown input leads to a buffer overflow vulnerability. CWE is classifying the issue as CWE-120. The product copies an input buffer to an output buffer without verifying that the size of the input buffer is less than the size of the output buffer, leading to a buffer overflow. This is going to have an impact on confidentiality, integrity, and availability. The summary by CVE is:

In the Linux kernel, the following vulnerability has been resolved: tls: fix handling of zero-length records on the rx_list Each recvmsg() call must process either - only contiguous DATA records (any number of them) - one non-DATA record If the next record has different type than what has already been processed we break out of the main processing loop. If the record has already been decrypted (which may be the case for TLS 1.3 where we don't know type until decryption) we queue the pending record to the rx_list. Next recvmsg() will pick it up from there. Queuing the skb to rx_list after zero-copy decrypt is not possible, since in that case we decrypted directly to the user space buffer, and we don't have an skb to queue (darg.skb points to the ciphertext skb for access to metadata like length). Only data records are allowed zero-copy, and we break the processing loop after each non-data record. So we should never zero-copy and then find out that the record type has changed. The corner case we missed is when the initial record comes from rx_list, and it's zero length.

The advisory is shared at git.kernel.org. This vulnerability is uniquely identified as CVE-2025-39682 since 04/16/2025. The exploitability is told to be easy. Technical details are known, but no exploit is available. The price for an exploit might be around USD $0-$5k at the moment (estimation calculated on 02/09/2026).

The vulnerability scanner Nessus provides a plugin with the ID 261606 (Linux Distros Unpatched Vulnerability : CVE-2025-39682), which helps to determine the existence of the flaw in a target environment.

Upgrading to version 6.1.149, 6.6.103, 6.12.44, 6.16.4 or 6.17-rc3 eliminates this vulnerability. Applying the patch 2902c3ebcca52ca845c03182000e8d71d3a5196f/c09dd3773b5950e9cfb6c9b9a5f6e36d06c62677/3439c15ae91a517cf3c650ea15a8987699416ad9/29c0ce3c8cdb6dc5d61139c937f34cb888a6f42e/62708b9452f8eb77513115b17c4f8d1a22ebf843 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 (261606) and CERT Bund (WID-SEC-2025-1988). If you want to get the best quality for vulnerability data then you always have to consider VulDB.

Affected

  • Debian Linux
  • Google Cloud Platform
  • Amazon Linux 2
  • Red Hat Enterprise Linux
  • Ubuntu Linux
  • SUSE Linux
  • Oracle Linux
  • NetApp FAS
  • NetApp AFF
  • NetApp ActiveIQ Unified Manager
  • SUSE openSUSE
  • RESF Rocky Linux
  • Open Source Linux Kernel
  • Microsoft Azure
  • Dell Secure Connect Gateway
  • IBM QRadar SIEM
  • IBM Security Verify Access
  • 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: 7.6
VulDB Meta Temp Score: 7.4

VulDB Base Score: 8.0
VulDB Temp Score: 7.6
VulDB Vector: 🔒
VulDB Reliability: 🔍

NVD Base Score: 7.1
NVD Vector: 🔒

CVSSv2info

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

Exploitinginfo

Class: Buffer overflow
CWE: CWE-120 / CWE-119
CAPEC: 🔒
ATT&CK: 🔒

Physical: Partially
Local: Yes
Remote: Partially

Availability: 🔒
Status: Not defined

EPSS Score: 🔒
EPSS Percentile: 🔒

Price Prediction: 🔍
Current Price Estimation: 🔒

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Nessus ID: 261606
Nessus Name: Linux Distros Unpatched Vulnerability : CVE-2025-39682

Threat Intelligenceinfo

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

Countermeasuresinfo

Recommended: Upgrade
Status: 🔍

0-Day Time: 🔒

Upgrade: Kernel 6.1.149/6.6.103/6.12.44/6.16.4/6.17-rc3
Patch: 2902c3ebcca52ca845c03182000e8d71d3a5196f/c09dd3773b5950e9cfb6c9b9a5f6e36d06c62677/3439c15ae91a517cf3c650ea15a8987699416ad9/29c0ce3c8cdb6dc5d61139c937f34cb888a6f42e/62708b9452f8eb77513115b17c4f8d1a22ebf843

Timelineinfo

04/16/2025 CVE reserved
09/05/2025 +142 days Advisory disclosed
09/05/2025 +0 days VulDB entry created
02/09/2026 +157 days VulDB entry last update

Sourcesinfo

Vendor: kernel.org

Advisory: git.kernel.org
Status: Confirmed

CVE: CVE-2025-39682 (🔒)
GCVE (CVE): GCVE-0-2025-39682
GCVE (VulDB): GCVE-100-322893
CERT Bund: WID-SEC-2025-1988 - Linux Kernel: Mehrere Schwachstellen ermöglichen Denial of Service

Entryinfo

Created: 09/05/2025 21:44
Updated: 02/09/2026 11:55
Changes: 09/05/2025 21:44 (58), 09/07/2025 12:18 (2), 09/09/2025 09:28 (7), 11/06/2025 15:58 (1), 11/26/2025 07:23 (1), 11/27/2025 15:09 (1), 01/03/2026 12:12 (1), 01/05/2026 10:32 (1), 01/27/2026 18:02 (11), 02/09/2026 11:55 (1)
Complete: 🔍
Cache ID: 216::103

If you want to get the best quality for vulnerability data then you always have to consider VulDB.

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