How severe is CVE-2026-39413?

CVE-2026-39413 has a CVSS 3.x base score of 4.2, rated medium severity. It is exploitable over network with high attack complexity, requires high privileges and user interaction. Impact on confidentiality is high, integrity none, and availability none.

Is CVE-2026-39413 being actively exploited?

It is not currently listed in CISA's KEV catalog. Its EPSS exploit-prediction score is 0% (5th percentile), an estimate of the probability of exploitation in the next 30 days.

What products are affected by CVE-2026-39413?

CVE-2026-39413 affects Hkuds Lightrag. See the affected-products list for the exact vulnerable versions.

How do I fix CVE-2026-39413?

Review the linked vendor and NVD advisories for patched versions and mitigations, then upgrade or apply the recommended workaround.

Does CVE-2026-39413 have an EU (EUVD) identifier?

Yes. CVE-2026-39413 is tracked in the ENISA EU Vulnerability Database (EUVD) as EUVD-2026-20601.

When was CVE-2026-39413 published?

CVE-2026-39413 was published on 2026-04-08 and last updated on 2026-06-17.

CVE-2026-39413

CVE-2026-39413 is a medium-severity vulnerability in Hkuds Lightrag with a CVSS 3.x base score of 4.2. It is not currently listed as actively exploited by CISA, and its EPSS exploit-prediction score is low. The underlying weakness is classified as CWE-347.

Key facts

Severity: Medium (CVSS 3.x base score 4.2)
EPSS exploit prediction: 0% (5th percentile)
Actively exploited: Not listed in CISA KEV
EU (EUVD) id: EUVD-2026-20601
Weakness: CWE-347
Affected product: Hkuds Lightrag
Published: 2026-04-08
Last modified: 2026-06-17

Description

LightRAG provides simple and fast retrieval-augmented generation. Prior to 1.4.14, the LightRAG API is vulnerable to a JWT algorithm confusion attack where an attacker can forge tokens by specifying 'alg': 'none' in the JWT header. Since the jwt.decode() call does not explicitly deny the 'none' algorithm, a crafted token without a signature will be accepted as valid, leading to unauthorized access. This vulnerability is fixed in 1.4.14.

Frequently asked questions

What is CVE-2026-39413?: LightRAG provides simple and fast retrieval-augmented generation. Prior to 1.4.14, the LightRAG API is vulnerable to a JWT algorithm confusion attack where an attacker can forge tokens by specifying 'alg': 'none' in the JWT header. Since the jwt.decode() call does not explicitly deny the 'none' algorithm, a crafted token without a signature will be accepted as valid, leading to unauthorized access. This vulnerability is fixed in 1.4.14.
How severe is CVE-2026-39413?: CVE-2026-39413 has a CVSS 3.x base score of 4.2, rated medium severity. It is exploitable over network with high attack complexity, requires high privileges and user interaction. Impact on confidentiality is high, integrity none, and availability none.
Is CVE-2026-39413 being actively exploited?: It is not currently listed in CISA's KEV catalog. Its EPSS exploit-prediction score is 0% (5th percentile), an estimate of the probability of exploitation in the next 30 days.
What products are affected by CVE-2026-39413?: CVE-2026-39413 affects Hkuds Lightrag. See the affected-products list for the exact vulnerable versions.
How do I fix CVE-2026-39413?: Review the linked vendor and NVD advisories for patched versions and mitigations, then upgrade or apply the recommended workaround.
Does CVE-2026-39413 have an EU (EUVD) identifier?: Yes. CVE-2026-39413 is tracked in the ENISA EU Vulnerability Database (EUVD) as EUVD-2026-20601.
When was CVE-2026-39413 published?: CVE-2026-39413 was published on 2026-04-08 and last updated on 2026-06-17.

References

Affected products (1)

cpe:2.3:a:hkuds:lightrag:*:*:*:*:*:*:*:*

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