---
id: CVE-2026-90774
title: >-
  rustypaste before 0.18.1 validates the destination path before applying the
  optional custom filename HTTP header, allowing attackers to bypass
  directory-escape checks
summary: >-
  rustypaste before 0.18.1 validates the destination path before applying the
  optional custom filename HTTP header, allowing attackers to bypass
  directory-escape checks. Attackers can supply path traversal sequences in the
  filename header …
severity: high
cvss: 7.5
cvssVector: 'CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:H/A:N'
cwe:
  - CWE-22
vendor: orhun
product: rustypaste
affected:
  - rustypaste < 0.18.1
published: '2026-09-13'
updated: '2026-09-14'
sourceUpdated: '2026-09-14T16:17:39.350'
source: NVD
sourceUrl: 'https://nvd.nist.gov/vuln/detail/CVE-2026-90774'
references:
  - url: 'https://github.com/orhun/rustypaste'
    label: disclosure@vulncheck.com
  - url: 'https://github.com/orhun/rustypaste/blob/v0.18.0/src/paste.rs'
    label: disclosure@vulncheck.com
  - url: >-
      https://github.com/orhun/rustypaste/commit/ac05d552596af4a8429d80f30d11f67117ce02c8
    label: disclosure@vulncheck.com
  - url: 'https://github.com/orhun/rustypaste/issues/622'
    label: disclosure@vulncheck.com
  - url: >-
      https://www.vulncheck.com/advisories/rustypaste-before-0.18.1-path-traversal-via-filename-header
    label: disclosure@vulncheck.com
  - url: 'https://github.com/orhun/rustypaste/issues/622'
    label: 134c704f-9b21-4f2e-91b3-4a467353bcc0
tags:
  - nvd
  - cve.org
  - exploit-available
epss: 0.00383
epssPercentile: 0.32085
ingestedAt: '2026-09-14T15:23:07.471Z'
exploitAvailable: true
ssvc:
  exploitation: poc
  automatable: 'yes'
  technicalImpact: partial
  timestamp: '2026-09-14T15:35:02.688496Z'
---

## Overview

rustypaste before 0.18.1 validates the destination path before applying the optional custom filename HTTP header, allowing attackers to bypass directory-escape checks. Attackers can supply path traversal sequences in the filename header to write files outside the configured upload directory to arbitrary locations.

## Remediation

Refer to the linked advisories for vendor-supplied fixes and affected version ranges.