CVE-2026-34444
published 2026-04-06CVE-2026-34444: Lupa integrates the runtimes of Lua or LuaJIT2 into CPython. In 2.6 and earlier, attribute_filter is not consistently applied when attributes are accessed…
PriorityP264critical10CVSS 3.1
AVNACLPRNUINSCCHIHAH
EPSS
0.61%
44.8th percentile
Lupa 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.
Affected
3 ranges
| Vendor | Product | Version range | Fixed in |
|---|---|---|---|
| debian | python-lupa | — | — |
| scoder | lupa | <= 2.6 | — |
| scoder | lupa | 0 – 2.6 | — |
Detection & IOCsextracted from sources · hover to see the quote
- →Monitor for abuse of Python built-in functions `getattr` and `setattr` within Lupa (lupa) Lua/LuaJIT2-CPython bridge contexts, which can be used to bypass attribute_filter restrictions and achieve arbitrary code execution ↗
- →Flag use of lupa version 2.6 or earlier in Python environments; the vulnerability is present in all versions up to and including 2.6 ↗
- →Audit Lupa-based sandboxing implementations that rely on attribute_filter for security enforcement — the filter can be bypassed via getattr/setattr, undermining any sandbox isolation ↗
- ·No fix is currently available for any tracked distribution (Debian bookworm, bullseye, forky, sid, trixie all remain open); Red Hat also notes no qualifying mitigation is available ↗
- ·Scope of exploitation is local per Debian security tracker classification, limiting remote attack surface ↗
- ·Multiple Red Hat OpenShift AI (RHOAI) pipeline and workbench container images are confirmed affected, broadening the enterprise impact surface beyond standalone lupa installs ↗
CVSS provenance
nvdv3.110.0CRITICALCVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:C/C:H/I:H/A:H
nvdv4.07.9HIGHCVSS:4.0/AV:N/AC:L/AT:N/PR:N/UI:N/VC:N/VI:N/VA:N/SC:H/SI:H/SA:H/E:X/CR:X/IR:X/AR:X/MAV:X/MAC:X/MAT:X/MPR:X/MUI:X/MVC:X/MVI:X/MVA:X/MSC:X/MSI:X/MSA:X/S:X/AU:X/R:X/V:X/RE:X/U:X
osv7.9HIGH
vendor_debian7.9HIGH
vendor_redhat7.9HIGH
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Red Hat
lupa: Lupa: Arbitrary Code Execution due to inconsistent attribute filtering
vendor_redhat·2026-04-06·CVSS 7.9
CVE-2026-34444 [HIGH] CWE-914 lupa: Lupa: Arbitrary Code Execution due to inconsistent attribute filtering
lupa: Lupa: Arbitrary Code Execution due to inconsistent attribute filtering
Lupa 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.
A flaw was found in Lupa, a tool that integrates Lua or LuaJIT2 runtimes into CPython. An attacker can exploit this vulnerability by bypassing attribute filtering mechanisms when accessing attributes through built-in functions like `getattr` and `setattr`. This inconsistency in applying security restrictions can allow an attacker to execute arbitrary code, potentially compromising the system.
Mitigat
Debian
CVE-2026-34444: python-lupa - Lupa integrates the runtimes of Lua or LuaJIT2 into CPython. In 2.6 and earlier,...
vendor_debian·2026·CVSS 7.9
CVE-2026-34444 [HIGH] CVE-2026-34444: python-lupa - Lupa integrates the runtimes of Lua or LuaJIT2 into CPython. In 2.6 and earlier,...
Lupa 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.
Scope: local
bookworm: open
bullseye: open
forky: open
sid: open
trixie: open
OSV
Lupa has a Sandbox escape and RCE due to incomplete attribute_filter enforcement in getattr / setattr
osv·2026-04-07
CVE-2026-34444 [HIGH] Lupa has a Sandbox escape and RCE due to incomplete attribute_filter enforcement in getattr / setattr
Lupa has a Sandbox escape and RCE due to incomplete attribute_filter enforcement in getattr / setattr
### Summary
The `attribute_filter` in the Lupa library is intended to restrict access to sensitive Python attributes when exposing objects to Lua.
However, the 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.
### Details
The `attribute_filter` is meant to block access to attributes such as `__class__`, `__mro__`, and similar internal properties.
In practice, it only applies to direct attribute access:
- `obj.attr` → filtered
- `getattr(obj, "attr")` → not filtered
Because of this inconsistency, it’s possible to
GHSA
Lupa has a Sandbox escape and RCE due to incomplete attribute_filter enforcement in getattr / setattr
ghsa·2026-04-07
CVE-2026-34444 [HIGH] CWE-284 Lupa has a Sandbox escape and RCE due to incomplete attribute_filter enforcement in getattr / setattr
Lupa has a Sandbox escape and RCE due to incomplete attribute_filter enforcement in getattr / setattr
### Summary
The `attribute_filter` in the Lupa library is intended to restrict access to sensitive Python attributes when exposing objects to Lua.
However, the 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.
### Details
The `attribute_filter` is meant to block access to attributes such as `__class__`, `__mro__`, and similar internal properties.
In practice, it only applies to direct attribute access:
- `obj.attr` → filtered
- `getattr(obj, "attr")` → not filtered
Because of this inconsistency, it’s possible to
OSV
CVE-2026-34444: Lupa integrates the runtimes of Lua or LuaJIT2 into CPython
osv·2026-04-06·CVSS 7.9
CVE-2026-34444 [HIGH] CVE-2026-34444: Lupa integrates the runtimes of Lua or LuaJIT2 into CPython
Lupa 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.
No detection rules found.
No public exploits indexed.
Bugzilla
CVE-2026-34444 lupa: Lupa: Arbitrary Code Execution due to inconsistent attribute filtering
bugzilla·2026-04-06·CVSS 7.9
CVE-2026-34444 [HIGH] CVE-2026-34444 lupa: Lupa: Arbitrary Code Execution due to inconsistent attribute filtering
CVE-2026-34444 lupa: Lupa: Arbitrary Code Execution due to inconsistent attribute filtering
Lupa 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.
Wiz
CVE-2026-34444 Impact, Exploitability, and Mitigation Steps | Wiz
blogs_wiz·CVSS 7.9
CVE-2026-34444 [HIGH] CVE-2026-34444 Impact, Exploitability, and Mitigation Steps | Wiz
## CVE-2026-34444 :
Python vulnerability analysis and mitigation
Lupa 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.
Source : NVD
## 7.9
Score
Published April 6, 2026
Severity HIGH
CNA Score 7.9
Affected Technologies
Python
Linux Debian
Has Public Exploit No
Has CISA KEV Exploit No
CISA KEV Release Date N/A
CISA KEV Due Date N/A
Exploitation Probability Percentile (EPSS) 20.9
Exploitation Probability (EPSS) 0.1
Affected packages and libraries
python-lupa
lupa
Sources
NVD
Debian 11, 14 No Fix Added at: Apr
2026-04-06
Published