CVE-2026-43891: CWE-73: External Control of File Name or Path in dgtlmoon changedetection.io
changedetection.io is a free open source web page change detection tool. Prior to 0.55.1, the vulnerability is caused by trusting attacker-controlled snapshot paths restored from backup files. The vulnerable flow starts in the backup restore logic. When a backup ZIP is restored, the application extracts the archive and copies each restored watch UUID directory directly into the live datastore using shutil.copytree(entry.path, dst_dir). This preserves attacker-controlled files inside the restored watch directory, including history.txt. After restore, the application parses history.txt in the watch history property and returns the contents of the targeted local file. This vulnerability is fixed in 0.55.1.
AI Analysis
Technical Summary
The vulnerability in changedetection.io (CVE-2026-43891) arises from the backup restore logic that trusts attacker-controlled snapshot paths within backup ZIP files. When restoring, the application uses shutil.copytree to copy directories from the archive directly into the live datastore, preserving any malicious files an attacker may have placed, including history.txt. After restoration, the application parses history.txt and returns its contents, enabling an attacker to control which local files are read and disclosed. This is classified as CWE-73 (External Control of File Name or Path). The issue is resolved in version 0.55.1.
Potential Impact
An attacker can craft a malicious backup ZIP file that, when restored, causes the application to read and disclose arbitrary local files by controlling the snapshot paths and contents of history.txt. This leads to a confidentiality breach (high impact on confidentiality) without affecting integrity or availability. There are no known exploits in the wild at this time.
Mitigation Recommendations
Upgrade changedetection.io to version 0.55.1 or later, where this vulnerability is fixed. Since the vendor advisory does not provide additional remediation details, applying the official fix is the recommended action. Patch status is not explicitly stated but the fix is available in version 0.55.1.
CVE-2026-43891: CWE-73: External Control of File Name or Path in dgtlmoon changedetection.io
Description
changedetection.io is a free open source web page change detection tool. Prior to 0.55.1, the vulnerability is caused by trusting attacker-controlled snapshot paths restored from backup files. The vulnerable flow starts in the backup restore logic. When a backup ZIP is restored, the application extracts the archive and copies each restored watch UUID directory directly into the live datastore using shutil.copytree(entry.path, dst_dir). This preserves attacker-controlled files inside the restored watch directory, including history.txt. After restore, the application parses history.txt in the watch history property and returns the contents of the targeted local file. This vulnerability is fixed in 0.55.1.
AI-Powered Analysis
Machine-generated threat intelligence
Technical Analysis
The vulnerability in changedetection.io (CVE-2026-43891) arises from the backup restore logic that trusts attacker-controlled snapshot paths within backup ZIP files. When restoring, the application uses shutil.copytree to copy directories from the archive directly into the live datastore, preserving any malicious files an attacker may have placed, including history.txt. After restoration, the application parses history.txt and returns its contents, enabling an attacker to control which local files are read and disclosed. This is classified as CWE-73 (External Control of File Name or Path). The issue is resolved in version 0.55.1.
Potential Impact
An attacker can craft a malicious backup ZIP file that, when restored, causes the application to read and disclose arbitrary local files by controlling the snapshot paths and contents of history.txt. This leads to a confidentiality breach (high impact on confidentiality) without affecting integrity or availability. There are no known exploits in the wild at this time.
Mitigation Recommendations
Upgrade changedetection.io to version 0.55.1 or later, where this vulnerability is fixed. Since the vendor advisory does not provide additional remediation details, applying the official fix is the recommended action. Patch status is not explicitly stated but the fix is available in version 0.55.1.
Technical Details
- Data Version
- 5.2
- Assigner Short Name
- GitHub_M
- Date Reserved
- 2026-05-04T15:17:09.330Z
- Cvss Version
- 3.1
- State
- PUBLISHED
- Remediation Level
- null
Threat ID: 6a036564cbff5d861008cca5
Added to database: 5/12/2026, 5:37:40 PM
Last enriched: 5/12/2026, 6:06:21 PM
Last updated: 5/13/2026, 4:49:43 AM
Views: 3
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