Linux Kernel up to 6.18.52 freevxfs fs/freevxfs/vxfs_bmap.c vxfs_bmap_typed input validation

CVSS Meta Temp Score
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Current Exploit Price (≈)
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CTI Interest Score
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6.2$0-$5k0.79

Summaryinfo

A vulnerability categorized as critical has been discovered in Linux Kernel up to 6.18.52. Impacted is the function vxfs_bmap_typed of the file fs/freevxfs/vxfs_bmap.c of the component freevxfs. Executing a manipulation can lead to input validation. This vulnerability is registered as CVE-2026-98872. It is possible to launch the attack remotely. No exploit is available. It is advisable to upgrade the affected component.

Detailsinfo

A vulnerability has been found in Linux Kernel up to 6.18.52 and classified as critical. This vulnerability affects the function vxfs_bmap_typed of the file fs/freevxfs/vxfs_bmap.c of the component freevxfs. The manipulation with an unknown input leads to a input validation vulnerability. The CWE definition for the vulnerability is CWE-20. The product receives input or data, but it does not validate or incorrectly validates that the input has the properties that are required to process the data safely and correctly. As an impact it is known to affect availability. CVE summarizes:

In the Linux kernel, the following vulnerability has been resolved: freevxfs: don't BUG() on unknown typed-extent type vxfs_bmap_typed() handles four typed-extent types and calls BUG() in its default case, so an on-disk typed extent with any other type value crashes the kernel. It is reachable from ioctl(FIBMAP) on a regular file: kernel BUG at fs/freevxfs/vxfs_bmap.c:230! RIP: vxfs_bmap_typed fs/freevxfs/vxfs_bmap.c:230 [inline] vxfs_bmap1+0x128a/0x12d0 fs/freevxfs/vxfs_bmap.c:257 Replace the BUG() with WARN_ON_ONCE() and return 0 -- the value vxfs_bmap_typed() already returns on failure (and from the DEV4 case above); vxfs_getblk() maps 0 to -EIO, so the ioctl fails cleanly.

The advisory is available at git.kernel.org. This vulnerability was named CVE-2026-98872 since 09/25/2026. The exploitation appears to be easy. The attack can be initiated remotely. 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 10/23/2026).

Upgrading to version 5.10.271, 5.15.222, 6.1.189, 6.6.158, 6.12.111 or 6.18.53 eliminates this vulnerability. Applying the patch fe40a19d571cbb584eea46038ee919d8712b2d2c/500e9d5bf9eff2096a21b7ac25a0a06ca46ab821/f1f2d54a576f0e4133b979e545abcfefd439c300/7ada9807e37103b41f586d34e3075e1209182b65/1284d687d46953fff9c0d969df108114611aca8b/405f13d7b270913e06e8e2b4de568985f94ef7d6/704d48d81dc41470e108811c32c577ada66192d4 is able to eliminate this problem. The best possible mitigation is suggested to be upgrading to the latest version.

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Productinfo

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Version

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CPE 2.3info

CPE 2.2info

CVSSv4info

VulDB Vector: 🔒
VulDB Reliability: 🔍

CVSSv3info

VulDB Meta Base Score: 6.5
VulDB Meta Temp Score: 6.2

VulDB Base Score: 6.5
VulDB Temp Score: 6.2
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: Input validation
CWE: CWE-20
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 5.10.271/5.15.222/6.1.189/6.6.158/6.12.111/6.18.53
Patch: fe40a19d571cbb584eea46038ee919d8712b2d2c/500e9d5bf9eff2096a21b7ac25a0a06ca46ab821/f1f2d54a576f0e4133b979e545abcfefd439c300/7ada9807e37103b41f586d34e3075e1209182b65/1284d687d46953fff9c0d969df108114611aca8b/405f13d7b270913e06e8e2b4de568985f94ef7d6/704d48d81dc41470e108811c32c577ada66192d4

Timelineinfo

09/25/2026 CVE reserved
10/23/2026 +28 days Advisory disclosed
10/23/2026 +0 days VulDB entry created
10/23/2026 +0 days VulDB entry last update

Sourcesinfo

Vendor: kernel.org

Advisory: git.kernel.org
Status: Confirmed

CVE: CVE-2026-98872 (🔒)
GCVE (CVE): GCVE-0-2026-98872
GCVE (VulDB): GCVE-100-425650

Entryinfo

Created: 10/23/2026 14:09
Changes: 10/23/2026 14:09 (60)
Complete: 🔍
Cache ID: 216::103

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