CVE-2026-85734 LightRAG: No Rate Limiting on /login Endpoint Allows Brute-Force Attacks
Attackers can brute-force login credentials due to missing rate limits, gaining unauthorized access to documents and admin functions.
- Exploited in the wild
- Not known
- Login needed
- Not needed
- Attackable
- Over the internet
- Victim action needed
- Not needed
- Fix
- Available
What is CVE-2026-85734?
CVE-2026-85734 is a critical authentication bypass vulnerability in HKUDS LightRAG, published on 22 Sep 2026. An attacker can exploit it over the internet without logging in, with no action from the victim.
Official description
LightRAG provides simple and fast retrieval-augmented generation. Prior to 1.5.5, the POST /login endpoint in lightrag/api/lightrag_server.py does not impose a rate limit, account lockout, delay, or counter for failed authentication attempts. A network attacker can submit password guesses at full request speed until a valid account password is found. Successful credential recovery grants authenticated access to documents, the knowledge graph, and administrative operations. This issue is fixed in version 1.5.5.
Weakness: CWE-307
Which versions are affected by CVE-2026-85734?
3 open source packages ship an affected version, including lightrag-hku.
| Package | Affected | Fixed in |
|---|---|---|
lightrag-hku PyPI | All versions | 1.5.5 |
lightrag-hku PyPI | All versions | 1.5.5 |
lightrag-hku PyPI | All versions | 1.5.5 |
How do I fix CVE-2026-85734?
Upgrade lightrag-hku to 1.5.5 or later.
Upgrade, and rotate credentials and sessions that may have been exposed. More about Authentication bypass.
Is CVE-2026-85734 being exploited?
There is no known exploitation of CVE-2026-85734 in the wild and no public exploit code.
Sources
Also known as GHSA-frch-4w6v-q5xx, PYSEC-2026-4062.