Severity by source
CVSS:4.0/AV:N/AC:L/AT:N/PR:N/UI:N/VC:N/VI:N/VA:N/SC:H/SI:N/SA:N/E:X/CR:X/IR:X/AR:X/MAV:X/MAC:X/MAT:X/MPR:X/MUI:X/MVC:X/MVI:X/MVA:X/MSC:X/MSI:X/MSA:X/S:X/AU:X/R:X/V:X/RE:X/U:X
Unauthenticated network SSRF (AV:N/AC:L/PR:N/UI:N) that pivots into other systems (S:C); reachable internal services and cloud IAM metadata make C:H, with no integrity or availability impact.
Primary rating from Vendor (VulnCheck).
CVSS VectorVendor: VulnCheck
Lifecycle Timeline
7DescriptionCVE.org
lmdeploy's OpenAI-compatible API server contains a server-side request forgery vulnerability that allows unauthenticated attackers to access internal services and cloud metadata endpoints by supplying a crafted image_url that redirects to internal targets. Attackers can send a POST request to the chat completions endpoint with an image_url pointing to an attacker-controlled server that responds with an HTTP 302 redirect to internal addresses such as loopback or instance-metadata endpoints, bypassing the initial URL safety check because redirects are followed without re-validating each hop through the safety guard.
AnalysisAI
Server-side request forgery in InternLM lmdeploy's OpenAI-compatible vision API server lets unauthenticated remote attackers coerce the server into fetching internal-only resources by abusing the image_url media-fetch path. Because the URL safety check validates only the initial URL and does not re-validate targets after an HTTP 302 redirect, an attacker-hosted endpoint can redirect the fetch to loopback services or cloud instance-metadata endpoints, exposing internal services and potentially cloud credentials. No public exploit is identified at time of analysis, EPSS is low (0.28%), and a vendor fix adding a media-domain allowlist is available.
Technical ContextAI
lmdeploy is an InternLM toolkit for compressing, deploying, and serving large language and vision-language models, exposing an OpenAI-compatible HTTP API (chat/completions) that accepts multimodal inputs. When a request includes an image_url, the server's multimodal media fetcher retrieves the remote image over HTTP(S). The root cause is CWE-918 (Server-Side Request Forgery): the private-IP/safety guard evaluates the user-supplied URL once, but the underlying HTTP client transparently follows redirects and each redirected hop is not re-checked against the guard. This time-of-check/time-of-use gap lets an initially benign-looking external URL pivot, via a 302 Location header, to RFC1918/loopback addresses or cloud metadata services (e.g., 169.254.169.254). The affected component is identified by CPE cpe:2.3:a:internlm:lmdeploy (all versions prior to the fix).
RemediationAI
Upgrade to a build of lmdeploy that contains the upstream fix in pull request #4734 / commit 03c313006d17cc3feae86b633c44206a997c44db; the upstream fix is available (PR/commit) but a released patched version tag is not independently confirmed from the provided data, so verify the exact release with the vendor. The fix adds a --allowed-media-domains startup option, so operators exposing the API server to untrusted clients should launch with an explicit hostname allowlist, e.g. lmdeploy serve api_server <model_path> --allowed-media-domains example.com (matching is exact-hostname, so cdn.example.com must be listed separately). Where immediate upgrade is not possible, apply compensating controls: place the API server behind an egress firewall/proxy that blocks outbound requests to RFC1918, loopback, and link-local ranges including 169.254.169.254 (trade-off: breaks legitimate internal image fetching); enforce IMDSv2 and disable IMDSv1 with a low hop limit on cloud instances to blunt metadata theft (trade-off: requires IMDSv2-aware tooling); and require authentication or network-level restriction in front of the chat/completions endpoint so anonymous clients cannot submit image_url values (trade-off: affects legitimate unauthenticated API consumers). See the VulnCheck advisory and the repository documentation update for details.
Remote code execution in InternLM LMDeploy versions 0.9.1 through 0.10.1 allows unauthenticated network attackers to run
Server-Side Request Forgery (SSRF) in InternLM LMDeploy's vision-language module allows remote unauthenticated attackers
Unauthenticated remote code execution in InternLM LMDeploy (versions 0.9.2 through 0.15.x) allows a remote attacker to e
A vulnerability was found in InternLM LMDeploy up to 0.7.1. Rated medium severity (CVSS 4.8), this vulnerability is low
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Memory exhaustion in InternLM LMDeploy through 0.17.0 can be triggered by unauthenticated remote attackers who send repe
Denial of service in InternLM LMDeploy through 0.17.0 lets unauthenticated remote attackers crash the distributed infere
Same weakness CWE-918 – Server-Side Request Forgery (SSRF)
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External POC / Exploit Code
Leaving vuln.today
EUVD-2026-46412
GHSA-rqhf-rg9p-w5gg