Security Digest · Vulnerability record
CVE-2024-32651: changedetection.io has a Server Side Template Injection using Jinja2 which allows Remote Command Execution
changedetection.io is an open source web page change detection, website watcher, restock monitor and notification service.
CVSS 10.0 Critical EPSS 83.6% · p99.7
Should you act?
High exploit likelihood
EPSS ranks it in the top 5% of all CVEs for likely exploitation in the next 30 days. This signal is computed from CISA KEV, EPSS and CVSS data; it is not an editorial verdict.
- Not in CISA KEV, but CISA’s SSVC assessment records a public proof-of-concept, so attack code exists.
- EPSS 83.6%, percentile 99.7: FIRST’s model estimates a 83.6% chance of exploitation activity in the next 30 days, higher than 99.7% of all scored CVEs (very high). EPSS is a probability, not a verdict.
- Remotely reachable with no login and no user interaction. If the vulnerable service is exposed to the internet, prioritize it.
- Only applies if your dependency tree includes
changedetection.io(PyPI) <= 0.45.20, fixed in 0.45.21. Check your lockfile, including transitive dependencies.
What it is
changedetection.io is an open source web page change detection, website watcher, restock monitor and notification service. There is a Server Side Template Injection (SSTI) in Jinja2 that allows Remote Command Execution on the server host. Attackers can run any system command without any restriction and they could use a reverse shell. The impact is critical as the attacker can completely takeover the server machine. This can be reduced if changedetection is behind a login page, but this isn't required by the application (not by default and not enforced).
From the GitHub advisory
Summary A Server Side Template Injection in changedetection.io caused by usage of unsafe functions of Jinja2 allows Remote Command Execution on the server host.
Details
changedetection.io version: 0.45.20
The vulnerability is caused by the usage of vulnerable functions of Jinja2 template engine.
PoC 1. Create/Edit a URL watch item 2. Under Notifications tab insert this payload:
Weakness type: CWE-1336.
Product: changedetection.io (PyPI) · Assigned by: GitHub_M · Published: 2024-04-25
Affected and fixed versions
| Ecosystem | Package | Vulnerable | First fixed |
|---|---|---|---|
| PyPI | changedetection.io | <= 0.45.20 | 0.45.21 |
| Vendor | Product | Affected versions (per CVE record) |
|---|---|---|
| dgtlmoon | changedetection.io | <= 0.45.20 |
Severity scores
| Scored by | CVSS | Score | Vector |
|---|---|---|---|
| GitHub_M | 3.1 | 10 Critical | CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:C/C:H/I:H/A:H |
| GitHub | 3.1 | 10.0 | CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:C/C:H/I:H/A:H |
- Attack vector: network (remotely reachable)
- Attack complexity: low
- Privileges required: none (no login)
- User interaction: none
- Scope: changed (can affect other components)
CVSS measures how bad a flaw is if exploited, not how likely exploitation is. Read it next to the exploitation data below.
Exploitation and urgency
- CISA KEV: not listed (no confirmed in-the-wild exploitation known to CISA).
- CISA SSVC assessment: exploitation poc, automatable yes, technical impact total.
- FIRST EPSS (model of 2026-10-21): 83.60% probability of exploitation activity in the next 30 days; percentile 99.7.
Timeline
- — CVE record published by GitHub_M
- — GitHub-reviewed advisory GHSA-4r7v-whpg-8rx3 published (critical)
- — CVE record last updated
Sources and references
Original sources first. Version and fix details should always be confirmed against the vendor or project advisory.
Vulnerability records
- GitHub Advisory GHSA-4r7v-whpg-8rx3 github.com
- CVE.org record CVE-2024-32651 cve.org
- NVD entry CVE-2024-32651 nvd.nist.gov
Other references from the CVE record and advisory
- github.com github.com
- github.com github.com
- onsecurity.io onsecurity.io
- blog.hacktivesecurity.com blog.hacktivesecurity.com