Vulnerability in changedetection.io (CVE-2026-43891)
Summary
Vulnerability in changedetection.io (CVE-2026-43891). Confidential information can be exposed externally. Exploitable via history.txt. Mitigation: upgrade to 0.55.1 or later.
Original description
The description as published by the source.
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.
Source: NIST National Vulnerability Database NVD GitHub Advisory
Auto-generated summary
Assembled by SecPulse from the source data (CVSS, CWE, affected versions) using templates — no AI involved. Check the original description and references below for exact details.
A vulnerability tracked as CVE-2026-43891 has been found in changedetection.io.
Attackers can target a specific entry point like history.txt over the network to misuse the product.
Confidential information can be exposed externally. CVSS score: 7.5/10.
What to do: upgrade changedetection.io to 0.55.1 or later.
If unsure, ask your IT team or search "changedetection.io CVE-2026-43891" on the vendor's site.
CVE-2026-43891 (changedetection.io) — CWE-73 / CVSS v3 7.5
Attack vector: remote (network-reachable) / unauthenticated / no user interaction
Attack surface: history.txt / history / self.data_dir / watch.data_dir
Patched: 0.55.1 — apply immediately
Plan: 1) Audit SBOM/dependencies, 2) Stage→prod upgrade, 3) Add WAF/proxy monitoring on affected endpoints, 4) Hunt IOCs in logs.
Refs: see the GHSA / vendor advisory / patched release linked on this page.
A vulnerability (CWE-73) exists in changedetection.io. Attackers reach the vulnerable code path via history.txt without authentication.
Check the vendor advisory for the affected versions of changedetection.io. Attack surface: history.txt / history / self.data_dir / watch.data_dir.
Severity: High (CVSS 7.5/10). Confidential information can be exposed externally.
Update to 0.55.1.
Until the patch is applied: disable the affected feature, apply WAF rules, or restrict access via network ACLs.
Search webserver/proxy logs for unusual request patterns matching this CVE's known IOCs. Run grep -r 'changedetection.io' . against your dependency files (package-lock.json, requirements.txt, go.sum) to find affected services.
Response actions
Concrete steps and command examples for SOC/SRE teams to execute in order
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1Identify exposure identify
grep -r 'changedetection.io' . | grep -v node_modulesリポジトリと本番環境の依存ファイル (package-lock.json / requirements.txt / go.sum / Gemfile.lock 等) で
changedetection.ioを grep し、稼働しているサービス・バージョンを把握する。 -
2Apply patch patch
Upgrade changedetection.io to 0.55.1ステージング環境で 0.55.1 に上げて回帰テスト → 本番反映。回帰テストはアプリの主要ハッピーパスを含めること。
-
3Post-deployment verification verify
Confirm patched version is live in productionパッチ適用後、ステージングで PoC または同等の悪用パターンを再現して脆弱性が閉じたことを確認。本番ではアクセスログ・WAF でアラート再発が無いか継続監視。
Affected packages
References
- advisory github.com
- advisory nvd.nist.gov
- advisory github.com
- advisory github.com
- package github.com
- report github.com
- web github.com