CVE-2026-45134LangSmith Client SDK: Public prompt pull deserializes untrusted manifests without trust boundary warning
- 7.1HighCVSS base score
- 0.20%Exploitation in 30 daysEPSS · top 90% of all CVEs
- NoKnown exploitednot in CISA's KEV catalog
- NonePublic exploitsnone known yet
Description
LangSmith Client SDKs provide SDK's for interacting with the LangSmith platform. Prior to LangSmith SDK Python 0.8.0 and JS/TS 0.6.0, the LangSmith SDK's prompt pull methods (pull_prompt / pull_prompt_commit in Python, pullPrompt / pullPromptCommit in JS/TS) fetch and deserialize prompt manifests from the LangSmith Hub. These manifests may contain serialized LangChain objects and model configuration that affect runtime behavior. When pulling a public prompt by owner/name identifier, the manifest content is controlled by an external party, but prior versions of the SDK did not distinguish this from pulling a prompt within the caller's own organization. This vulnerability is fixed in LangSmith SDK Python 0.8.0 and JS/TS 0.6.0.
Timeline
ID reserved
By GitHub_M
- 19 days later
· 19 days later
Published
- 6 days later
· 6 days later
Record updated
Changes after publication (a new score, a public exploit, EPSS crossing 1, 10 or 50 %, leaving KEV) are kept since November 2026; earlier ones are not known.
Scores
| Scored by | CVSS | Score | Vector |
|---|---|---|---|
| GitHub_MCNA (assigner) | 3.1 | High7.1 | CVSS:3.1/AV:N/AC:L/PR:N/UI:R/S:U/C:H/I:L/A:N |
| NVDNVD · Awaiting Analysis | 3.1 | High7.1 | CVSS:3.1/AV:N/AC:L/PR:N/UI:R/S:U/C:H/I:L/A:N |
- EPSS (exploitation in 30 days)
- 0.20% · top 90% of all CVEs (12 Nov 2026)
- CISA SSVC
- Exploitation: none · Automatable: no · Technical impact: partial
The list uses the assigner's score when there is one, then CISA's, then NVD's: High 7.1.
Affected products
- affected < 0.8.0
- affected < 0.6.0
Affected packages
Affected packages4
From reviewed advisories of the GitHub Advisory Database.
- PyPIlangchainGHSA-3644-q5cj-c5c7 (opens in a new tab)
- PyPIlangchain-classicGHSA-3644-q5cj-c5c7 (opens in a new tab)
- PyPIlangsmithGHSA-3644-q5cj-c5c7 (opens in a new tab)
- npmlangsmithGHSA-3644-q5cj-c5c7 (opens in a new tab)
References
References1
Sources
The same CVE in the primary databases and aggregators, to check against.
- CVE.org record (opens in a new tab)
- CVE List JSON (GitHub) (opens in a new tab)
- NVD (opens in a new tab)
- FIRST EPSS (opens in a new tab)
- EUVD EUVD-2026-32640 (opens in a new tab)
- OSV.dev (opens in a new tab)
- GitHub Advisory GHSA-3644-q5cj-c5c7 (opens in a new tab)
- CIRCL Vulnerability-Lookup (opens in a new tab)
Badge for a README or a ticket
[](https://cveledger.app/cve/CVE-2026-45134)Record last updated .