CVE-2026-28208
MEDIUMCVE-2026-28208 is a medium-severity (CVSS 5.9) Path Traversal vulnerability in com.github.junrar:junrar. O3 Security confirms whether CVE-2026-28208 is actually reachable in your code before you act, and blocks exploitation at runtime until you patch.
Junrar has arbitrary file write due to backslash path traversal bypass in LocalFolderExtractor on Linux/Unix
Blast Radius
com.github.junrar:junrarReal-time download stats are indexed for npm and PyPI packages. This vulnerability affects Maven packages — download data is not available via public APIs for these ecosystems.
Description
Junrar is an open source java RAR archive library. Prior to version 7.5.8, a backslash path traversal vulnerability in LocalFolderExtractor allows an attacker to write arbitrary files with attacker-controlled content anywhere on the filesystem when a crafted RAR archive is extracted on Linux/Unix. This can often lead to remote code execution (e.g., overwriting shell profiles, source code, cron jobs, etc). Version 7.5.8 has a fix for the issue.
Affected Packages
| Ecosystem | Package | Vulnerable range | Fix |
|---|---|---|---|
| ☕Maven | com.github.junrar:junrar | all versions | 7.5.8 |
Detection & mitigation playbook
Open-source dependencyDetect
Scan your dependency tree (package-lock.json, pnpm-lock.yaml, requirements.txt, go.sum, etc.) for com.github.junrar:junrar. 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 com.github.junrar:junrar to 7.5.8 or later, then make sure no transitive (indirect) dependency still pins the vulnerable range — O3 confirms CVE-2026-28208 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-2026-28208 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-2026-28208. 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-2026-28208 in your dependencies?
O3 detects CVE-2026-28208 across Maven dependencies and uses function-level reachability to confirm whether the vulnerable code path is actually reachable — not just present. No false positives.