Summary
Hydra logging configuration permits unsafe callable resolution
Hydra passed its Python logging configuration to logging.config.dictConfig(). Python's logging configurator can resolve and invoke importable classes and factories named by configuration, including handler class values and formatter, filter, handler, queue, and listener () factories.
This logging path was not mediated by Hydra's target policy. In versions that already protected instantiate(), logging resolution bypassed those controls because it did not use instantiate().
An attacker who can control a Hydra logging configuration can use a custom class or factory to execute code with the application's privileges when Hydra configures logging.
Remediation
Upgrade to Hydra 1.3.6, or to Hydra 1.4.0.dev9 or later when testing the 1.4 prerelease line.
On Hydra 1.3, do not compose logging configuration from untrusted sources. On Hydra 1.4 and later, constrain custom logging targets with a narrow execution whitelist supplied by trusted Python code. The execution whitelist controls callable selection; it is not general validation of all logging settings.
For Hydra 1.4 execution-whitelist configuration, see:
Impact
Untrusted input is evaluated as executable code within the application's runtime environment. Typical impact: arbitrary code execution within the application's privilege context.
CVE-2026-106441 has a CVSS score of 7.8 (High). The vector is requires local access, no privileges required, and user interaction required. A CVSS score reflects the worst-case severity of the vulnerability, not your specific exposure. Whether this affects your application depends on whether the vulnerable code is present and reachable in your environment. A fixed version is available (1.3.6, 1.4.0.dev9); upgrading removes the vulnerable code path.
Affected versions
Security releases
Kodem intelligence
Severity tells you how bad this could be in the worst case. It does not tell you whether you are exposed. Exploitability and impact are functions of runtime truth: whether the vulnerable code is present, reachable, and actually executes in your application. A vulnerable package can sit in your dependency tree and never run.
Kodem, an Intelligent Application Security platform, uses runtime intelligence to reveal which vulnerabilities actually execute in production, so teams prioritize the ones that genuinely matter. Kodem's runtime-powered SCA identifies whether this CVE is reachable in your applications.
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Hydra now applies its target policy to callable resolution and invocation in Hydra-configured Python logging. It authorizes custom factories, handlers, formatters, filters, queues, listeners, aliases, discovery results, and callable results before they can be used.
Hydra 1.3.6 uses the hardened blacklist. The Hydra 1.3 blacklist is a best-effort, defense-in-depth measure. It is not a complete security boundary and does not make untrusted logging configuration safe.
Hydra 1.4.0.dev9 introduces the execution whitelist as the recommended primary boundary, with the blacklist retained as a deprecated compatibility fallback. When an execution whitelist is supplied, Hydra automatically permits targets used by its built-in logging configurations, while custom logging integrations must be explicitly authorized by trusted Python code. If no whitelist is supplied, Hydra warns and preserves legacy fallback behavior.
Frequently Asked Questions
- What is CVE-2026-106441? CVE-2026-106441 is a high-severity code injection vulnerability in hydra-core (pip), affecting versions < 1.3.6. It is fixed in 1.3.6, 1.4.0.dev9. Untrusted input is evaluated as executable code within the application's runtime environment.
- How severe is CVE-2026-106441? CVE-2026-106441 has a CVSS score of 7.8 (High). This score reflects the worst-case severity of the vulnerability, not your specific exposure. Whether it represents real risk in your environment depends on whether the vulnerable code is present and reachable.
- Which versions of hydra-core are affected by CVE-2026-106441? hydra-core (pip) versions < 1.3.6 is affected.
- Is there a fix for CVE-2026-106441? Yes. CVE-2026-106441 is fixed in 1.3.6, 1.4.0.dev9. Upgrade to this version or later.
- Is CVE-2026-106441 exploitable, and should I be worried? Whether CVE-2026-106441 is exploitable in your environment depends on whether the vulnerable code is present and reachable. A CVSS score is a worst-case rating; it does not account for your specific deployment, configuration, or usage patterns. Kodem, an Intelligent Application Security platform, uses runtime intelligence to show which vulnerabilities actually execute in production, so you can focus on the ones that represent real risk. Get a demo
- What actually determines whether CVE-2026-106441 is exploitable, and how bad it is? Exploitability and impact are not fixed properties of a CVE. They depend on runtime truth: whether the vulnerable code is present, reachable, and actually executes in your application. A high CVSS score on a dependency that never runs is not the same as real risk. Kodem, an Intelligent Application Security platform, uses runtime intelligence to reveal which vulnerabilities actually execute in production, so teams prioritize the ones that genuinely matter.
- How do I fix CVE-2026-106441?
- Upgrade
hydra-coreto 1.3.6 or later - Upgrade
hydra-coreto 1.4.0.dev9 or later
- Upgrade