CVE intelligence and bounded remediation
CVE-2025-9799 — A security flaw has been discovered in Langfuse up to 3.88.0
A security flaw has been discovered in Langfuse up to 3.88.0. Affected by this vulnerability is the function promptChangeEventSourcing of the file web/src/features/prompts/server/routers/promptRouter.ts of the component Webhook Handler. Performing manipulation results in server-side request forgery. The attack may be initiated remotely. A high degree of complexity is needed for the attack. The exploitation appears to be difficult. The exploit has been released to the public and may be exploited.
- Severity
- Medium
- CVSS
- 5 (3.1)
- Published
- 2025-09-01
- CISA KEV
- Not currently listed
- Ecosystem
- software/application
- Weaknesses
- CWE-918
Affected products
- langfuse / langfuse
Matched remediation archetype
Server-side request forgery and unintended proxying
This catalog composition supplies bounded fallback guidance. Explicitly reviewed curated workflows load with the complete record below.
Check exposure
- Inventory server-side URL fetchers, webhooks, importers, previews, redirects, proxies, and protocol handlers reachable from untrusted input.
- Map egress paths to internal services, metadata endpoints, loopback, private address space, and privileged control planes.
- Review DNS resolution, redirect, proxy, credential-forwarding, and URL parsing behavior without requesting sensitive targets.
Remediate safely
- Replace arbitrary destinations with named integrations or a strict allowlist of schemes, hosts, ports, and paths.
- Resolve and validate every destination and redirect hop, then enforce egress policy independently of application checks.
- Remove ambient credentials and sensitive headers from fetchers; apply response size, time, and content limits.
Authoritative sources
Complete CVE record and remediation plan
The detailed catalog view below loads this exact record, its source evidence, and the full seven-phase agentic change plan.