Vulnerability · Published Sep 22, 2026 · Assigned by GitHub_M

CVE-2026-85734LightRAG: No Rate Limiting on /login Endpoint Allows Brute-Force Attacks

Critical 9.1

In plain English

A critical-severity security flaw in LightRAG from HKUDS. There are no confirmed reports of exploitation so far. The chance it is exploited in the next 30 days is estimated at 0.6% (higher than 49% of all known vulnerabilities). Fixed versions are available - upgrade the affected package.

Severity (CVSS 3.1)9.1Critical

Exploit odds (30 days)0.6%top 50.6% of all CVEs

Exploited in the wildNo reportsCISA SSVC: none

Attack toolingNoneno public tooling known

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.

Affected packages & fixed versions

Ecosystem	Package	Fixed in	Advisory
PyPI	lightrag-hku	1.5.5	GHSA-frch-4w6v-q5xx
PyPI	lightrag-hku	1.5.5	PYSEC-2026-4062

Affected products (as reported)

Vendor	Product	Versions
HKUDS	LightRAG	< 1.5.5

Weakness: CWE-307 · Vector: CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:H/A:N

References

https://github.com/HKUDS/LightRAG/security/advisories/GHSA-frch-4w6v-q5xx x_refsource_CONFIRM
https://github.com/HKUDS/LightRAG/pull/3424 x_refsource_MISC
https://github.com/HKUDS/LightRAG/commit/135bc9056e9ecd800c1abe2f2ce24d1a86622a54 x_refsource_MISC
https://github.com/HKUDS/LightRAG/releases/tag/v1.5.5 x_refsource_MISC