CVE-2026-61736: LightRAG: CORS Wildcard + Credentials Enables Any-Origin Credentialed Requests

Should you act?

Critical and remotely reachable

No known exploitation yet, but it is network-reachable without credentials. This signal is computed from CISA KEV, EPSS and CVSS data; it is not an editorial verdict.

• No confirmed exploitation. It is not in CISA’s KEV catalog and CISA’s SSVC assessment records no known exploitation. That can change quickly after a public write-up; re-check if you are affected.
• EPSS 1.4%, percentile 73: FIRST’s model estimates a 1.4% chance of exploitation activity in the next 30 days, higher than 73% of all scored CVEs (moderate). EPSS is a probability, not a verdict.
• Needs a user to click or open something. Phishing makes that realistic, but it is not wormable.
• Only applies if your dependency tree includes lightrag-hku (PyPI) <= 1.5.3, fixed in 1.5.4. Check your lockfile, including transitive dependencies.

What it is

LightRAG provides simple and fast retrieval-augmented generation. Prior to 1.5.4, the server defaults to CORSORIGINS= combined with allowcredentials=True in lightrag/api/lightragserver.py, causing Starlette CORSMiddleware to effectively whitelist every origin for credentialed cross-origin requests. Any malicious website visited by an authenticated LightRAG user can silently make authenticated API requests, exfiltrating documents and knowledge graph data or performing destructive actions such as deleting the document store. This vulnerability is fixed in 1.5.4.

From the GitHub advisory

Summary The server defaults to CORSORIGINS= combined with allowcredentials=True. Starlette's CORSMiddleware echoes the requesting origin in preflight responses when credentials are enabled, meaning every origin is effectively whitelisted for credentialed cross-origin requests. Any malicious website can perform authenticated API calls on behalf of a logged-in user.

Details

PoC

Host on any origin. Open in browser where user is logged in to LightRAG:

Impact Permissive cross-domain policy (CWE-942). Any website visited by an authenticated LightRAG user can silently make authenticated API requests, exfiltrating all documents and knowledge graph data or performing destructive actions such as deleting the entire document store.

Weakness type: CWE-942.

Product: lightrag-hku (PyPI) · Assigned by: GitHub_M · Published: 2026-07-15

Affected and fixed versions

Severity scores

• Attack vector: network (remotely reachable)
• Attack complexity: low
• Privileges required: none (no login)
• User interaction: required (a user must click/open something)
• Scope: changed (can affect other components)

CVSS measures how bad a flaw is if exploited, not how likely exploitation is. Read it next to the exploitation data below.

Exploitation and urgency

• CISA KEV: not listed (no confirmed in-the-wild exploitation known to CISA).
• CISA SSVC assessment: exploitation none, automatable no, technical impact total.
• FIRST EPSS (model of 2026-10-21): 1.42% probability of exploitation activity in the next 30 days; percentile 73.

Timeline

• 2026-07-15 — CVE record last updated
• 2026-07-15 — CVE record published by GitHub_M
• 2026-07-20 — GitHub-reviewed advisory GHSA-6x6h-qqr7-855w published (critical)

Sources and references

Original sources first. Version and fix details should always be confirmed against the vendor or project advisory.

Vulnerability records

1. GitHub Advisory GHSA-6x6h-qqr7-855w github.com
2. CVE.org record CVE-2026-61736 cve.org
3. NVD entry CVE-2026-61736 nvd.nist.gov

Other references from the CVE record and advisory

1. github.com github.com
2. github.com github.com
3. github.com github.com
4. github.com github.com
5. github.com github.com
6. github.com github.com

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