What it is
CVE-2025-10164 is an unauthenticated lmsys sglang update_weights_from_tensor main deserialization. A security flaw has been discovered in lmsys sglang 0.4.6. Affected by this vulnerability is the function main of the...
Vulnerability report
Exploited in the wild
High confidence
Not in CISA KEV
CVE-2025-10164
lmsys sglang update_weights_from_tensor main deserialization
lmsys / sglang · 0.4.6
- Severity
- CVSS 6.9 · Medium
- Confidence
- High
- Exploit status
- Exploited in the wild
- EPSS
- 0.4%
- First observed
- —
- Last observed
- —
Decision summary
What security teams need to know first
Direct answers before the deeper technical record.
Is it exploited?
Yes. Previdian tracks this CVE as a known exploited vulnerability. Confidence is high.
Who is affected?
lmsys / sglang 0.4.6.
What should we do?
Prioritize remediation. Validate affected assets and apply vendor fixes on an accelerated timeline.
Overview
A security flaw has been discovered in lmsys sglang 0.4.6
A security flaw has been discovered in lmsys sglang 0.4.6. Affected by this vulnerability is the function main of the file /update_weights_from_tensor. The manipulation of the argument serialized_named_tensors results in deserialization. The attack can be launched remotely. The exploit has been released to the public and may be exploited. The vendor was contacted early about this disclosure but did not respond in any way.
In lmsys sglang 0.4.6 ist eine Schwachstelle entdeckt worden. Dabei geht es um die Funktion main der Datei /update_weights_from_tensor. Die Bearbeitung des Arguments serialized_named_tensors verursacht deserialization. Der Angriff lässt sich über das Netzwerk starten. Der Exploit ist öffentlich verfügbar und könnte genutzt werden.
Vendor
Product
Affected
Status
lmsys
sglang
0.4.6
Affected
- Published
- 09 Sep 2025
- Exploitation Reported
- 22 Aug 2026
- Attack vector
- Remote
- Complexity
- Low
- Privileges
- None
- User interaction
- None
CVE References
- CVE Record CVE.org · CVE Record https://www.cve.org/CVERecord?id=CVE-2025-10164
- Submit #635919 | lmsys sglang >=0.4.6 Deserialization vuldb.com · Third-Party Advisory https://vuldb.com/?submit.635919
- VDB-323203 | lmsys sglang update_weights_from_tensor main deserialization vuldb.com · Technical Description https://vuldb.com/?id.323203
- VDB-323203 | CTI Indicators (IOB, IOC, IOA) vuldb.com · Signature https://vuldb.com/?ctiid.323203
Exploitation evidence
Why Previdian marks this CVE as exploited
Third-party attestation and first-party sensor observation are shown separately so teams can judge the evidence chain.
Exploited in the wild
The Shadowserver
Independent exploitation attestation added to the Previdian record.
Known exploited vulnerability sources
Per-source evidence links for KEV attestations are available through the Previdian Pro API.
Learn about Pro API access| Source | Added |
|---|---|
| The Shadowserver First | 2026-08-22 00:00 UTC |
Detection
Operational artifacts and observed signals
Make the evidence actionable in scanner, SOC, and edge-control workflows.
Observed signals
- Request targets
- 0
- User-Agents
- 0
Raw values available in Pro and Enterprise.
Scanner coverage
No scanner integrations recorded yet.
Virtual patch status
No Previdian virtual patch is currently available. Future rules ship for ModSecurity, Cloudflare, and AWS WAF.
Learn about virtual patches →No detection artifacts or sensor request patterns are available for this CVE yet.
Check back as sensor telemetry and scanner integrations are updated.
Risk and context
Severity, weaknesses, and research context
CVSS v4.0
6.9
Medium
CVSS:4.0/AV:N/AC:L/AT:N/PR:N/UI:N/VC:L/VI:L/VA:L/SC:N/SI:N/SA:N/E:P
EPSS
0.4%
All CVSS Scores
CVSS v4.0
6.9
Medium
CVSS:4.0/AV:N/AC:L/AT:N/PR:N/UI:N/VC:L/VI:L/VA:L/SC:N/SI:N/SA:N/E:P
CVSS v3.1
7.3
High
CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:L/I:L/A:L
CVSS v3.0
7.3
High
CVSS:3.0/AV:N/AC:L/PR:N/UI:N/S:U/C:L/I:L/A:L/E:P/RL:X/RC:R
CVSS v2.0
7.5
High
AV:N/AC:L/Au:N/C:P/I:P/A:P
Timeline
From disclosure to observed exploitation
-
Added to Previdian KEV Feed
High-confidence, third-party attested exploitation
-
CVE published
Vulnerability disclosed publicly
-
CVE ID reserved
Identifier reserved by the CNA
Pro API
Automate this intelligence
Confidence, exploit status, sensor telemetry, PoCs, scanner integrations, mentions, and tags are available programmatically for VM, SOC, and CTI workflows.
- Evidence confidence and provenance
- First-party sensor telemetry
- PoC and scanner references
- Affected versions and enrichment
- Automation-ready JSON delivery
GET /api/v2/pro/kevs/CVE-2025-10164
Free JSON includes basic KEV fields{
"cve_id": "CVE-2025-10164",
"confidence": "High",
"cvss_score": 6.9,
"cvss_estimated": false,
"epss_score": 0.00404,
"exploit_status": {
"exploited_in_the_wild": true,
"active_exploitation_observed": false
},
"sensor_telemetry": { "attempts": 0, "sensors": 0 }
}Early warning alerts
Get alerts on high-impact exploitation
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