langgraph-sdk

CVE-2026-48776

CVE-2026-48776 is a medium-severity path traversal vulnerability in langgraph-sdk (pip), affecting versions < 0.3.15. It is fixed in 0.3.15.

Key facts
CVSS score
4.2
Medium
Attack vector
Network
Issuing authority
GitHub Advisory Database
Affected package
langgraph-sdk
Fixed in
0.3.15
Disclosed
2026

Summary

Summary langgraph-sdk constructs HTTP request paths for resource operations by interpolating caller-supplied identifier values into URL templates. Without sanitization of those values, identifiers that contain characters with special meaning in URL paths could cause the resulting request to address a different resource (and potentially a different resource type) than the SDK method's call site indicates. In deployments where the SDK receives identifier values that originate from untrusted sources, this could result in unintended access, modification, or deletion of resources beyond the calling user's authorization scope. This issue is most consequential in deployments that: forward end-user-supplied values directly into SDK identifier parameters without first validating them against an expected format (such as a UUID), and rely on URL-prefix-based authorization at an upstream layer (reverse proxy, edge gateway, WAF), where the authorization decision is made on the SDK call's intended path rather than on the final delivered request path. There have no evidence of this behavior being triggered in the wild. This change is intended to reduce the surface available when caller-supplied identifier values originate from untrusted sources. Affected users / systems You may be affected if you: use langgraph-sdk (Python) to address resources by identifier, and pass identifier values into SDK methods that originate from end-user input, untrusted third-party callers, or any source that does not validate identifier format before the SDK call. Applications that validate identifier values (for example, by parsing them as UUIDs and rejecting anything that does not parse) before passing them to SDK methods are not affected. Validated UUIDs round-trip through the SDK request path unchanged. Impact Potential unintended access, modification, or deletion of resources via SDK methods called for a different resource type, when caller-supplied identifier values are not validated. In deployments with prefix-based authorization at an upstream layer, the authorization decision and the final delivered request path may diverge. Confidentiality: disclosure of resource content beyond the authorization scope of the calling user. Integrity: modification or deletion of resources beyond the authorization scope of the calling user. Patches / mitigation The SDK now applies path-segment encoding to identifier values before they are interpolated into request URL templates. After this change, identifier values that contain characters with special meaning in URL paths are transmitted as encoded byte sequences and routed to the resource the SDK method's call site indicates. Compatibility Identifier values that match the standard UUID format, or any other format that contains only characters safe to transmit unencoded in URL path segments, round-trip through the SDK request path unchanged. Applications that already validate identifier inputs see no behavioral change. Operational guidance Validate identifier values (typically as UUIDs) at the boundary where untrusted input enters the application, before passing them to SDK methods. For deployments relying on URL-prefix-based authorization upstream of LangGraph, prefer authorization at the LangGraph server layer or on parsed-and-validated request paths rather than on raw URL prefixes. LangSmith / hosted deployments note This issue affects the SDK that runs in caller applications. The LangGraph server runtime, including LangSmith-hosted deployments, receives ordinary HTTP requests on documented routes and is not itself affected by this issue. Applications that consume LangSmith-hosted services via langgraph-sdk and pass untrusted identifier values to SDK methods should upgrade. First reported by: pucagit (CyStack).

Impact

What is path traversal?

Input manipulates file paths to reach files outside the intended directory, such as configuration or credential files. Typical impact: unauthorized file read or write outside the intended directory.

Severity and exposure

CVE-2026-48776 has a CVSS score of 4.2 (Medium). The vector is network-reachable, low privileges required, and no user interaction. 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 (0.3.15). Upgrading removes the vulnerable code path.

Affected versions

pip

  • langgraph-sdk (< 0.3.15)

Security releases

  • langgraph-sdk → 0.3.15 (pip)
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 instead of chasing every advisory.

Kodem's runtime-powered SCA identifies whether CVE-2026-48776 is reachable in your applications. Explore open-source security for your team.

See if CVE-2026-48776 is reachable in your applications. Get a demo

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Remediation advice

Upgrade langgraph-sdk to 0.3.15 or later to resolve this vulnerability.

Kodem Kai can prioritize this vulnerability in your dependency tree and generate a fix recommendation.

Frequently asked questions about CVE-2026-48776

What is CVE-2026-48776?

CVE-2026-48776 is a medium-severity path traversal vulnerability in langgraph-sdk (pip), affecting versions < 0.3.15. It is fixed in 0.3.15. Input manipulates file paths to reach files outside the intended directory, such as configuration or credential files.

How severe is CVE-2026-48776?

CVE-2026-48776 has a CVSS score of 4.2 (Medium). 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 langgraph-sdk are affected by CVE-2026-48776?

langgraph-sdk (pip) versions < 0.3.15 is affected.

Is there a fix for CVE-2026-48776?

Yes. CVE-2026-48776 is fixed in 0.3.15. Upgrade to this version or later.

Is CVE-2026-48776 exploitable, and should I be worried?

Whether CVE-2026-48776 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-2026-48776 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-2026-48776?

Upgrade langgraph-sdk to 0.3.15 or later.

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