CVE-2026-77781
Fix: davorg-cpan/tie-hash-regex@4239732CVE-2026-77781 is a CWE-248 vulnerability. O3 Security confirms whether CVE-2026-77781 is actually reachable in your code before you act, and blocks exploitation at runtime until you patch.
Tie::Hash::Regex versions before 2.0.0 for Perl will throw an exception on unparseable lookup keys
Description
Tie::Hash::Regex versions before 2.0.0 for Perl will throw an exception on unparseable lookup keys.
The FETCH, EXISTS and DELETE methods throw an exception when on malformed regular expressions.
Each method falls back to a regex match when the key is not already stored in the hash, compiling the caller's key with a bare qr// and no eval guard. A key that is not a valid regular expression pattern, such as a single unmatched bracket, dies.
An application that looks up externally supplied strings in a tied hash will die on an invalid key.
Detection & mitigation playbook
VulnerabilityDetect
Scan your dependency tree (package-lock.json, pnpm-lock.yaml, requirements.txt, go.sum, etc.) for the affected component. 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.
Remediation status
No patched version of the affected component has shipped for CVE-2026-77781 yet. Where your build allows, override or pin the dependency away from the vulnerable range, and apply any maintainer-recommended mitigation.
Mitigate without a patch
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-2026-77781 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-2026-77781. 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-2026-77781 in your dependencies?
O3 detects CVE-2026-77781 across dependencies and uses function-level reachability to confirm whether the vulnerable code path is actually reachable — not just present. No false positives.