Linux Kernel up to 6.17.3 ext4 parse_apply_sb_mount_options buffer overflow

CVSS Meta Temp Score
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CTI Interest Score
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7.6$0-$5k0.00

Summaryinfo

A vulnerability was found in Linux Kernel up to 6.17.3 and classified as critical. Affected by this vulnerability is the function parse_apply_sb_mount_options of the component ext4. Executing a manipulation can lead to buffer overflow. This vulnerability is handled as CVE-2025-40198. There is not any exploit available. It is suggested to upgrade the affected component.

Detailsinfo

A vulnerability has been found in Linux Kernel up to 6.17.3 and classified as critical. This vulnerability affects the function parse_apply_sb_mount_options of the component ext4. The manipulation with an unknown input leads to a buffer overflow vulnerability. The CWE definition for the vulnerability is 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. As an impact it is known to affect confidentiality, integrity, and availability. CVE summarizes:

In the Linux kernel, the following vulnerability has been resolved: ext4: avoid potential buffer over-read in parse_apply_sb_mount_options() Unlike other strings in the ext4 superblock, we rely on tune2fs to make sure s_mount_opts is NUL terminated. Harden parse_apply_sb_mount_options() by treating s_mount_opts as a potential __nonstring.

The advisory is available at git.kernel.org. This vulnerability was named CVE-2025-40198 since 04/16/2025. The exploitation appears to be easy. Technical details are known, but there is no available exploit. The structure of the vulnerability defines a possible price range of USD $0-$5k at the moment (estimation calculated on 02/07/2026).

The vulnerability scanner Nessus provides a plugin with the ID 275363 (Linux Distros Unpatched Vulnerability : CVE-2025-40198), which helps to determine the existence of the flaw in a target environment.

Upgrading to version 5.4.301, 5.10.246, 6.1.158, 6.6.114, 6.12.54, 6.17.4 or 6.18-rc1 eliminates this vulnerability. Applying the patch 7bf46ff83a0ef11836e38ebd72cdc5107209342d/b2bac84fde28fb6a88817b8b761abda17a1d300b/e651294218d2684302ee5ed95ccf381646f3e5b4/01829af7656b56d83682b3491265d583d502e502/2a0cf438320cdb783e0378570744c0ef0d83e934/a6e94557cd05adc82fae0400f6e17745563e5412/8ecb790ea8c3fc69e77bace57f14cf0d7c177bd8 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 (275363) and CERT Bund (WID-SEC-2025-2595). If you want to get best quality of vulnerability data, you may have to visit VulDB.

Affected

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

Productinfo

Type

Vendor

Name

Version

License

Website

CPE 2.3info

CPE 2.2info

CVSSv4info

VulDB Vector: 🔒
VulDB Reliability: 🔍

CVSSv3info

VulDB Meta Base Score: 8.0
VulDB Meta Temp Score: 7.6

VulDB Base Score: 8.0
VulDB Temp Score: 7.6
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: Buffer overflow
CWE: CWE-120 / CWE-119
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: 275363
Nessus Name: Linux Distros Unpatched Vulnerability : CVE-2025-40198

Threat Intelligenceinfo

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

Countermeasuresinfo

Recommended: Upgrade
Status: 🔍

0-Day Time: 🔒

Upgrade: Kernel 5.4.301/5.10.246/6.1.158/6.6.114/6.12.54/6.17.4/6.18-rc1
Patch: 7bf46ff83a0ef11836e38ebd72cdc5107209342d/b2bac84fde28fb6a88817b8b761abda17a1d300b/e651294218d2684302ee5ed95ccf381646f3e5b4/01829af7656b56d83682b3491265d583d502e502/2a0cf438320cdb783e0378570744c0ef0d83e934/a6e94557cd05adc82fae0400f6e17745563e5412/8ecb790ea8c3fc69e77bace57f14cf0d7c177bd8

Timelineinfo

04/16/2025 CVE reserved
11/13/2025 +211 days Advisory disclosed
11/13/2025 +0 days VulDB entry created
02/07/2026 +86 days VulDB entry last update

Sourcesinfo

Vendor: kernel.org

Advisory: git.kernel.org
Status: Confirmed

CVE: CVE-2025-40198 (🔒)
GCVE (CVE): GCVE-0-2025-40198
GCVE (VulDB): GCVE-100-332266
CERT Bund: WID-SEC-2025-2595 - Linux Kernel: Mehrere Schwachstellen

Entryinfo

Created: 11/13/2025 07:31
Updated: 02/07/2026 20:37
Changes: 11/13/2025 07:31 (59), 11/13/2025 19:32 (2), 11/14/2025 05:27 (7), 12/01/2025 14:33 (1), 12/21/2025 22:01 (1), 02/07/2026 20:37 (1)
Complete: 🔍
Cache ID: 216::103

If you want to get best quality of vulnerability data, you may have to visit VulDB.

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