CVE-2026-45377 is a medium-severity (CVSS 6.5) Information Exposure vulnerability in decidim-core. O3 Security confirms whether CVE-2026-45377 is actually reachable in your code before you act, and blocks exploitation at runtime until you patch.
Decidim: Private exports can be downloaded through reusable links
Real-World Exposure
decidim-core💎decidim-core💎decidim-coreReal-time download stats are indexed for npm and PyPI packages. This vulnerability affects RubyGems packages — download data is not available via public APIs for these ecosystems.
Description
Decidim is a participatory democracy framework. Prior to 0.30.9, from 0.31.0 before 0.31.5, and in 0.32.0.rc1 before 0.32.0.rc2, the normal download_your_data flow requires the requester to be logged in as the export owner, but the resulting Active Storage blob redirect URL can be replayed without authentication by anyone who obtains it. This is because Decidim::DownloadYourDataController#download_file authenticates the export owner but redirects to a signed Active Storage blob URL that is no longer bound to the owner session. This issue is fixed in versions 0.30.9, 0.31.5, and 0.32.0.rc2.
Affected Packages
| Ecosystem | Package | Vulnerable range | Fix |
|---|---|---|---|
| 💎RubyGems | decidim-core | all versions | 0.30.9 |
| 💎RubyGems | decidim-core | ≥ 0.31.0.rc1&&< 0.31.5 | 0.31.5 |
| 💎RubyGems | decidim-core | ≥ 0.32.0.rc1&&< 0.32.0 | 0.32.0 |
Detection & mitigation playbook
Open-source dependencyDetect
Scan your dependency tree (package-lock.json, pnpm-lock.yaml, requirements.txt, go.sum, etc.) for decidim-core. O3's reachability analysis confirms whether the vulnerable code path is actually invoked in your application, so you act on real exposure instead of every transitive match.
Fix
Update decidim-core to 0.30.9 or later, then make sure no transitive (indirect) dependency still pins the vulnerable range — O3 confirms CVE-2026-45377 is resolved across your whole dependency graph.
Workarounds
If you can't upgrade right away: gate or disable the affected feature, validate untrusted input at the boundary, and avoid passing attacker-controlled data into the vulnerable path. O3's runtime protection blocks exploitation in production as an interim safeguard until the upgrade lands.
How O3 protects you
O3 pinpoints whether CVE-2026-45377 is reachable in your code and exactly where to fix it, then blocks exploitation in production at runtime until the patched version is deployed.
Tailored to CVE-2026-45377. Runtime protection reduces exposure until a permanent patch is applied and verified — it complements patching, it doesn't replace it.
Frequently Asked Questions
Is CVE-2026-45377 in your dependencies?
O3 detects CVE-2026-45377 across RubyGems dependencies and uses function-level reachability to confirm whether the vulnerable code path is actually reachable — not just present. No false positives.