Vulnerability record

CVE-2021-27850

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Full record read. Reported values and explicit gaps below come from the tracked record. Tracker snapshot: Aug 8, 2026.

What it is

Reported

A critical unauthenticated remote code execution vulnerability was found all recent versions of Apache Tapestry. The affected versions include 5.4.5, 5.5.0, 5.6.2 and 5.7.0. The vulnerability I have found is a bypass of the fix for CVE-2019-0195. Recap: Before the fix of CVE-2019-0195 it was possible to download arbitrary class files from the classpath by providing a crafted asset file URL. An attacker was able to download the file `AppModule.class` by requesting the URL `http://localhost:8080/assets/something/services/AppModule.class` which contains a HMAC secret key.… Source description excerpt; complete tracked detail loads below.

NVD published: Apr 15, 2021 · Source record updated: Aug 8, 2026 · Tracker snapshot: Aug 8, 2026

What is affected

Reported

Apache — tapestry. Product-level identification only; no affected-version conclusion is available from this field.

NVD published: Apr 15, 2021 · Source record updated: Aug 8, 2026 · Tracker snapshot: Aug 8, 2026

Urgency and basis

Reported

Act · 459.5

Tracker decision tier from the evidence detailed below · Source record updated: Aug 8, 2026 · Tracker snapshot: Aug 8, 2026

Exploitation evidence

Reported

kev-listed · VulnCheck KEV

VulnCheck KEV added: Dec 3, 2023 · Source record updated: Aug 8, 2026 · Tracker snapshot: Aug 8, 2026

What to do

Reported

Apply remediations or mitigations per vendor instructions or discontinue use of the product if remediation or mitigations are unavailable.

Source remediation ↗

Tracked source remediation field · Source record updated: Aug 8, 2026 · Tracker snapshot: Aug 8, 2026

Evidence detail

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