CVE-2026-41491 is a high-severity (CVSS 8.1) Path Traversal vulnerability in github.com/dapr/dapr. A fix is available for github.com/dapr/dapr — see the affected versions and patch details below.
Dapr: Service Invocation path traversal ACL bypass
Exploitation Status
No confirmed exploitation observed yet
- A successful exploit gives an attacker total control of the affected component, not partial access.
- CISA’s own triage has not observed active exploitation or public proof-of-concept code for this CVE as of its last assessment.
Exploitation and automatability from CISA’s SSVC triage for CVE-2026-41491.
EPSS Exploitation Probability
EPSS (Exploit Prediction Scoring System) is a daily probability model maintained by FIRST.org. It estimates the likelihood a CVE will be exploited in production environments within the next 30 days, derived from real-world threat intelligence signals.
How urgent is this, really
CVE-2026-41491 plotted by exploitation likelihood (EPSS) against impact (CVSS). The shaded corner — EPSS 50%+ and CVSS 7.0+ — is where this CVE doesn't sit, though severity or exploitability alone can still warrant action.
Where this sits among everything scored
Of 378,567 CVEs with a current EPSS score, this one falls in the < 10% band (highlighted). Real counts from FIRST.org, not a sample — log-scaled since the landscape is heavily right-skewed.
Real-World Exposure
github.com/dapr/dapr🐹github.com/dapr/dapr🐹github.com/dapr/daprReal-time download stats are indexed for npm and PyPI packages. This vulnerability affects Go packages — download data is not available via public APIs for these ecosystems.
Description
Summary
A vulnerability has been found in Dapr that allows bypassing access control policies for service invocation using reserved URL characters and path traversal sequences in method paths. The ACL normalized the method path independently from the dispatch layer, so the ACL evaluated one path while the target application received a different one.
Users who have configured access control policies for service invocation are strongly encouraged to upgrade Dapr to the respective patch version 1.17.5, 1.16.14, and 1.15.14.
Impact
This vulnerability impacts Dapr users who have configured access control policies for service invocation. An attacker who can reach the Dapr HTTP or gRPC API could:
- Use encoded path traversal (ex:
admin%2F..%2Fpublic) to reach an allowed path while the method started from a denied prefix. - Use encoded fragment (
%23) or query (%3F) characters to cause the ACL to evaluate a different path than what was delivered to the target application.
Patches
Users should upgrade immediately to their respective Dapr version 1.17.5, 1.16.14, and 1.15.14.
Details
Dapr supports access control policies for service invocation, which allow operators to restrict which methods an application is permitted to call on a target app. When a request arrives, Dapr evaluates the method path against the configured policy before dispatching to the target.
Prior to this fix, the ACL and the dispatch layer normalized the method path independently. The ACL used purell.NormalizeURLString, which decoded %XX sequences, resolved ../, and stripped # and ? as URL delimiters. The dispatch layer used the raw method string. This mismatch meant the ACL authorized one path while the target application received a different one.
For example, a method of admin%2F..%2Fpublic was normalized by the ACL to public (allowed), but the target application received admin/../public.
The gRPC API was the more dangerous vector because gRPC passes method strings raw — #, ?, ../, and control characters were all delivered literally with no client-side sanitization.
References
This PR signaled to us about the CVE, special thanks to @dbconfession78 for the efforts here and the original PR.
Affected Packages
| Ecosystem | Package | Vulnerable range | Fix |
|---|---|---|---|
| 🐹Go | github.com/dapr/dapr | ≥ 1.17.0-rc.1&&< 1.17.5 | 1.17.5go get github.com/dapr/dapr@v1.17.5 |
| 🐹Go | github.com/dapr/dapr | ≥ 1.16.0-rc.1&&< 1.16.14 | 1.16.14go get github.com/dapr/dapr@v1.16.14 |
| 🐹Go | github.com/dapr/dapr | ≥ 1.3.0&&< 1.15.14 | 1.15.14go get github.com/dapr/dapr@v1.15.14 |
Detection & mitigation playbook
Open-source dependencyDetect
Scan your dependency tree (package-lock.json, pnpm-lock.yaml, requirements.txt, go.sum, etc.) for github.com/dapr/dapr, including transitive dependencies — a direct dependency you never call can still pull in a vulnerable version.
Fix
Update github.com/dapr/dapr to 1.17.5 or later, then make sure no transitive (indirect) dependency still pins the vulnerable range — O3 confirms CVE-2026-41491 is resolved across your whole dependency graph.
Workarounds
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 Security's impact-aware SCA analyses which vulnerable code paths your application actually calls, so a match like CVE-2026-41491 can be triaged on real exposure rather than presence alone.
Tailored to CVE-2026-41491. 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-2026-41491 in your dependencies?
O3 Security finds CVE-2026-41491 across Go dependencies, including transitive ones, and its impact-aware SCA ranks findings by whether your code actually calls the vulnerable path.