---
title: "CVE-2026-48753: Incus has an arbitrary file write via path traversal in S3 multipart upload"
url: https://erroneo.us/security/cve/CVE-2026-48753/
description: "CVE-2026-48753 (github.com/lxc/incus/v7/cmd/incusd (Go)): Incus is a system container and virtual machine manager. Prior to version 7.1.0, the S3 protocol…"
type: vulnerability-record
section: "Security Digest"
date_published: 2026-08-21
date_modified: 2026-08-21
publisher: erroneo.us
author: erroneo.us Security Desk
cve: "CVE-2026-48753"
kev: false
cvss: 9.9
epss: 0.00731
license: All rights reserved. Quote with attribution and a link.
---

# CVE-2026-48753: Incus has an arbitrary file write via path traversal in S3 multipart upload

**Signal:** Critical, preconditions apply. Severe if exploited, but exploitation needs conditions that may not apply to you. (Computed from CISA KEV, EPSS and CVSS; not an editorial verdict.)

## Should you act?

- Not in CISA KEV , but CISA’s SSVC assessment records a public proof-of-concept, so attack code exists.
- EPSS 0.7% , percentile 54: FIRST’s model estimates a 0.7% chance of exploitation activity in the next 30 days, higher than 54% of all scored CVEs (moderate). EPSS is a probability, not a verdict.
- Needs an account (low (any account)). Exposure depends on who can log in.
- Only applies if your dependency tree includes github.com/lxc/incus/v7/cmd/incusd (Go) < 7.1.0, fixed in 7.1.0 . Check your lockfile, including transitive dependencies.

## What it is

Incus is a system container and virtual machine manager. Prior to version 7.1.0, the S3 protocol upload endpoint is vulnerable to path traversal and allows creation of arbitrary files on the host. This behavior could lead to arbitrary command execution. Version 7.1.0 fixes the issue.

## Affected packages

- Go `github.com/lxc/incus/v7/cmd/incusd` < 7.1.0 → fixed: 7.1.0

## Affected products (CVE record)

- lxc incus: < 7.1.0

## Severity

- GitHub_M CVSS 3.1: 9.9 `CVSS:3.1/AV:N/AC:L/PR:L/UI:N/S:C/C:H/I:H/A:H`
- GitHub CVSS 3.1: 9.9 `CVSS:3.1/AV:N/AC:L/PR:L/UI:N/S:C/C:H/I:H/A:H`

## Exploitation

- CISA KEV: not listed (no confirmed in-the-wild exploitation known to CISA).
- CISA SSVC assessment: exploitation poc , automatable no , technical impact total .
- FIRST EPSS (model of 2026-10-21): 0.73% probability of exploitation activity in the next 30 days; percentile 54.

## Sources

- [GitHub Advisory GHSA-ccjc-4qc3-jxqc](https://github.com/advisories/GHSA-ccjc-4qc3-jxqc)
- [CVE.org record CVE-2026-48753](https://www.cve.org/CVERecord?id=CVE-2026-48753)
- [NVD entry CVE-2026-48753](https://nvd.nist.gov/vuln/detail/CVE-2026-48753)
- [github.com](https://github.com/lxc/incus/security/advisories/GHSA-ccjc-4qc3-jxqc)

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Source page: https://erroneo.us/security/cve/CVE-2026-48753/ · Security Digest: https://erroneo.us/security/ · More: https://erroneo.us/llms.txt