LupaApplication · Scoder
CVE-2026-34444
Official description Straight from the sourceThe vendor's or NVD's own wording, published unedited. Authoritative, but often terse — it says what broke, rarely what to do.
NVD · uneditedLupa integrates the runtimes of Lua or LuaJIT2 into CPython. In 2.6 and earlier, attribute_filter is not consistently applied when attributes are accessed through built-in functions like getattr and setattr. This allows an attacker to bypass the intended restrictions and eventually achieve arbitrary code execution.
Technical summary Written by usOur analysis, written from the advisory, the CVSS vector and the affected-version data. It adds context the advisory leaves out, and never invents facts that are not in the source.
dbcve analysis · high confidenceLupa is a Python library embedding Lua/LuaJIT runtimes. It provides an attribute_filter security mechanism to restrict attribute access on Lua objects. In version 2.6 and earlier, this filter is not applied when attributes are accessed through Python's built-in getattr() and setattr() functions, allowing attackers to bypass intended restrictions and achieve arbitrary code execution.
Verify against the referenced sources before acting — the references below are authoritative for this CVE, this summary is not.
Affected products & versions What the vendor confirmedThe version ranges the vendor confirmed as vulnerable. If your version sits inside a range here, treat yourself as exposed until you have upgraded.
NVD · CPE data
LupaApplication
<= 2.6CVSS breakdown How the score is builtThe industry scoring standard. It rates how the flaw is reached, what it takes to exploit, and what an attacker gains — the score is derived from those, not the other way round.
From the vector- Attack vector
- Network
- Complexity
- Low
- Privileges
- None
- User interaction
- None
- Scope
- Changed
- Confidentiality
- High
- Integrity
- High
- Availability
- High
CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:C/C:H/I:H/A:H
Am I affected? How to checkSteps we derive from the advisory and the affected-version data, so you can decide whether this CVE reaches your setup. They are a guide, not a scan — your own configuration is the authority.
dbcve checksWork through these to decide whether this CVE applies to you.
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Check if Lupa is installedRun 'pip show lupa' or 'python -c "import lupa; print(lupa.__version__)"' to see if Lupa is present and its versionAffected if Lupa version is 2.6 or lower
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Identify attribute_filter usageSearch your codebase for 'attribute_filter' references, particularly in Python code that uses Lupa to wrap Lua objectsAffected if attribute_filter is configured and used in your code
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Check for getattr/setattr on Lupa objectsSearch your codebase for patterns like 'getattr(lua_object,' or 'setattr(lua_object,' where lua_object is a Lupa-wrapped Lua objectAffected if getattr or setattr are used to access or modify attributes on Lupa-wrapped objects that should be restricted by attribute_filter
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Verify bypass condition existsTest accessing a filtered attribute via direct access (obj.filtered_attr) versus getattr(obj, 'filtered_attr') - if direct access is blocked but getattr succeeds, the vulnerability is presentAffected if Direct attribute access enforces the filter while getattr/setattr bypasses it, allowing access to restricted attributes
You are affected if you use Lupa version 2.6 or lower with attribute_filter enabled, and your code accesses Lupa-wrapped object attributes through getattr or setattr functions rather than direct attribute access.
Generated from the published advisory. Verify against your own configuration.
Remediation Closing itWhat it takes to close this. Where a vendor fix exists we point at it; where none exists we say so plainly, and can build one. Effort estimates are scoped from the advisory, not from your codebase.
From vendor dataUpgrade to a Lupa version newer than 2.6 that applies attribute_filter consistently to built-in function access, or implement additional access controls around Lua execution contexts until patching is possible.
Fix this in Lupa
Scoped from the published advisory
- Consultation4.0 h
- Implementation8.0 h
- Testing6.0 h
- Review / QA2.0 h
An estimate, not a bill — we confirm scope with you before any work starts. Need it this week? Rush from $5,600.
Scan for this in your stack
Free · runs locallyCheck whether your project pulls in CVE-2026-34444 — or any other known-vulnerable package — straight from your lock files. Free and open source; it runs locally and uploads nothing.
References Go to the primary sourcePrimary sources — vendor advisories, patches and trackers. Where our summary and a reference disagree, the reference wins.
Primary sourcesPractitioner notes
ContributedPeer-ranked notes from engineers who’ve handled CVE-2026-34444 in production — separate from our analysis above.
The advisory tells you what broke. It rarely tells you what actually worked. If you’ve dealt with this one, that detail is what the next engineer is searching for.
- The version that genuinely resolved it — not the one the vendor claimed
- A config change or rule that shut the vector down
- A gotcha in the upgrade path that cost you an afternoon
No notes yet
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