# CVE-2025-37947 — Linux

> As of 2026-08-05, CVE-2025-37947 is a HIGH-severity vulnerability in Linux, CVSS v3.1 8.8, EPSS 0.6% (48.6th percentile). Threadlinqs Intelligence links 1 tracked threat campaign to CVE-2025-37947, most recently “CVE-2025-37947: Out-of-Bounds Write in Linux ksmbd Kernel SMB Server Enables Local Privilege Escalation”.

**Last updated:** 2026-08-05

## What is CVE-2025-37947?

In the Linux kernel, the following vulnerability has been resolved: ksmbd: prevent out-of-bounds stream writes by validating *pos ksmbd_vfs_stream_write() did not validate whether the write offset (*pos) was within the bounds of the existing stream data length (v_len). If *pos was greater than or equal to v_len, this could lead to an out-of-bounds memory write. This patch adds a check to ensure *pos is less than v_len before proceeding. If the condition fails, -EINVAL is returned.

The record classifies CVE-2025-37947 under weakness class [CWE-787](https://intel.threadlinqs.com/cwe/CWE-787). Its CVSS v3 base vector states that the flaw is reachable remotely over the network, needs low-privilege credentials, needs no user interaction, and has high impact on confidentiality, integrity, availability. 1 affected-product entry is recorded, across 1 vendor, listed below. The identifier was first published 520 days ago.

## Severity and exploitation probability

- **CVSS v3.1 base score:** 8.8 — HIGH (`CVSS:3.1/AV:N/AC:L/PR:L/UI:N/S:U/C:H/I:H/A:H`)
- **EPSS (FIRST):** 0.6% probability of exploitation in the next 30 days, higher than 48.6% of all scored CVEs
- **CISA KEV:** Not listed in the CISA Known Exploited Vulnerabilities catalog
- **Threadlinqs priority:** 8.3/10 — a Threadlinqs composite of the CVSS base score, the EPSS percentile and public exploit availability
- **Published:** 2025-05-20, last modified 2026-08-05

## Is CVE-2025-37947 being exploited?

Weaponised exploit code for CVE-2025-37947 is publicly available. 2 public proof-of-concept repositories are tracked for this identifier. It currently carries a trending score of 25 in the Threadlinqs vulnerability feed.

- [doyensec/KSMBD-CVE-2025-37947](https://github.com/doyensec/KSMBD-CVE-2025-37947) (github)
- [trickest/cve](https://github.com/trickest/cve/blob/main/2025/CVE-2025-37947.md) (trickest)

## Affected products and versions

- [Linux](https://intel.threadlinqs.com/vendors/linux): Linux

## How to fix CVE-2025-37947

No vendor patch reference has been recorded for CVE-2025-37947 in the tracked sources. Follow the references below for a fix, and treat the products listed above as exposed until the vendor states otherwise.

## Threat activity tracking CVE-2025-37947

1 tracked threat in the Threadlinqs corpus references CVE-2025-37947, either in the campaign’s CVE list or as an indicator on the campaign record.

- [CVE-2025-37947: Out-of-Bounds Write in Linux ksmbd Kernel SMB Server Enables Local Privilege Escalation](https://intel.threadlinqs.com/threat/TL-2026-2477) — HIGH · 2026-09-13

## Sources

Enriched from CVE.org, FIRST EPSS, public proof-of-concept repositories. Last verified by Threadlinqs on 2026-10-10.

**Other references**

- [git.kernel.org](https://git.kernel.org/stable/c/7f61da79df86fd140c7768e668ad846bfa7ec8e1)
- [git.kernel.org (04c8a38c60346bb5a7c49b276de7233f703ce9cb)](https://git.kernel.org/stable/c/04c8a38c60346bb5a7c49b276de7233f703ce9cb)
- [git.kernel.org (d62ba16563a86aae052f96d270b3b6f78fca154c)](https://git.kernel.org/stable/c/d62ba16563a86aae052f96d270b3b6f78fca154c)
- [git.kernel.org (e6356499fd216ed6343ae0363f4c9303f02c5034)](https://git.kernel.org/stable/c/e6356499fd216ed6343ae0363f4c9303f02c5034)
- [git.kernel.org (0ca6df4f40cf4c32487944aaf48319cb6c25accc)](https://git.kernel.org/stable/c/0ca6df4f40cf4c32487944aaf48319cb6c25accc)

Canonical: https://intel.threadlinqs.com/cve/CVE-2025-37947
Full detection coverage and IOCs for threats exploiting CVE-2025-37947 via the Threadlinqs MCP server (Purple tier): https://intel.threadlinqs.com/mcp