CVE-2026-118667: Unencoded identifiers in LangGraph SDK v3 streaming can redirect authenticated GET requests
Affects skillspectorSource GCVE Database
Not known to be exploited · CVSS 4.3 Medium.
Data as of 30 Oct 2026, 06:59 UTC
Thin evidence
One scorer or none| CNA (GitHub_M) | CVSS 3.1 | 4.3 |
|---|
- EPSS
- 0.3% chance of exploitation in 30 days – higher than 33% of CVEsExploit Prediction Scoring System: the likelihood attackers will use this flaw soon.
CVSS:3.1/AV:N/AC:L/PR:L/UI:N/S:U/C:L/I:N/A:NExploitation evidence
Disclosed: evidence found.
CVE published 28 Oct 2026
Detectable: no evidence on record.
No public nuclei template indexed
Weaponized: no evidence on record.
No public exploit code indexed in Metasploit or Exploit-DB
Exploited in the wildExploited: no evidence on record.
Not in CISA KEV and no source reports exploitation
Observed by OffSeq MirageSeen by Mirage: no evidence on record.
No attack traffic recorded by OffSeq Mirage sensors
A missing step is not evidence of safety. Sources: cve.org (opens in a new tab), the Metasploit, Exploit-DB and nuclei-templates index as of 29 Oct 2026.
What to do
Affected software
| Product | Affected | Fixed in |
|---|---|---|
Homebrewskillspectorpkg:brew/skillspectorOther threats | Affected
| Fixed in– |
Check your own hosts for these packages with threat-finder (opens in a new tab), our free open-source scanner.
Description
### Summary The LangGraph Python SDK v3 streaming client interpolates caller-supplied `thread_id` and `assistant_id` values into request paths without encoding them at four synchronous and asynchronous call sites. Relative path segments can therefore redirect an authenticated GET request to another path on the same configured server. ### Details The affected `get_tree` and `_fetch_state` implementations build request paths from raw identifiers rather than passing each identifier through the SDK's existing `_quote_path_param` helper. HTTP path normalization can collapse values containing relative segments before dispatch while retaining the client's authentication headers. `langgraph-sdk` versions 0.4.0 through 0.4.5 are affected. The v3 stream module is not present in the 0.3.x release line. `RemoteGraph` v3 streaming in `langgraph` 1.2.3 and later is also affected when used with a vulnerable `langgraph-sdk` version. It passes `config["configurable"]["thread_id"]` into `threads.stream(...)`, and its dependency range permits affected SDK versions. ### Impact An application is affected only if it passes attacker-controlled text as a streaming `thread_id` or `assistant_id`. In that configuration, an attacker may select another readable path on the configured server and cause the SDK to return that response to the application. Through `thread_id`, the attacker can also control the query string, for example by targeting `/store/items?namespace=...&key=...`; `assistant_id` controls only the path. The affected requests are GET operations, so this issue does not provide a write primitive. The LangGraph Platform is not exposed to this issue. ### Remediation Upgrade `langgraph-sdk` to version 0.4.6 or later. The fix encodes `assistant_id` in `get_tree` and `thread_id` in `_fetch_state` with `_quote_path_param` in both synchronous and asynchronous stream modules. If you use `RemoteGraph`, also upgrade `langgraph` to version 1.2.14 or later, which requires `langgraph-sdk>=0.4.6`.
References
- github.com/langchain-ai/langgraph/security/advisories/GHSA-3fx2-cqw9-xr3c (opens in a new tab)
- github.com/langchain-ai/langgraph/pull/9213 (opens in a new tab)
- github.com/langchain-ai/langgraph/commit/d89c7e100ec6fc1512544d23b0a7c5169699ef3e (opens in a new tab)
- github.com/langchain-ai/langgraph (opens in a new tab)
- github.com/langchain-ai/langgraph/releases/tag/1.2.14 (opens in a new tab)
- github.com/langchain-ai/langgraph/releases/tag/sdk%3D%3D0.4.6 (opens in a new tab)