Vulnerability in litestar (CVE-2026-48061)
Summary
Vulnerability in litestar (CVE-2026-48061). Data can be tampered with by attackers. Exploitable via Host header. Mitigation: upgrade to 2.22.0 or later.
Original description
The description as published by the source.
Summary
AllowedHostsMiddleware trusts the X-Forwarded-Host header as a fallback when the Host header is absent. Since X-Forwarded-Host is a client-controllable header, an attacker can bypass the allowed hosts validation by omitting the Host header and supplying an X-Forwarded-Host header set to a whitelisted domain. This enables host header injection attacks such as password reset poisoning, cache poisoning, and server-side request routing manipulation.
Details
In AllowedHostsMiddleware.__call__, the host value used for validation is resolved as follows:
https://github.com/litestar-org/litestar/blob/main/litestar/middleware/allowed_hosts.py#L68
headers = MutableScopeHeaders(scope=scope)
if host := headers.get("host", headers.get("x-forwarded-host", "")).split(":")[0]:
if self.allowed_hosts_regex.fullmatch(host):
await self.app(scope, receive, send)
return
When Host is absent (e.g., HTTP/1.0 clients, misconfigured proxies, or raw TCP connections), the middleware falls back to X-Forwarded-Host without any verification that the request actually passed through a trusted reverse proxy.
An attacker can send a request with no Host header and set X-Forwarded-Host to any whitelisted domain, bypassing the entire allowed hosts check. The application then processes the request as if it originated from a trusted host.
This is particularly dangerous when applications use the resolved host value for:
- Generating passwo…
Source: GitHub Security Advisories (Global) NVD GitHub Advisory
Auto-generated summary
Assembled by SecPulse from the source data (CVSS, CWE, affected versions) using templates — no AI involved. Check the original description and references below for exact details.
A vulnerability tracked as CVE-2026-48061 has been found in litestar.
Attackers can target a specific entry point like Host header over the network to misuse the product.
Data can be tampered with by attackers. CVSS score: 5.9/10.
What to do: upgrade litestar to 2.22.0 or later.
If unsure, ask your IT team or search "litestar CVE-2026-48061" on the vendor's site.
CVE-2026-48061 (litestar) — CWE-348 / CVSS v3 5.9
Attack vector: remote (network-reachable) / unauthenticated / no user interaction
Attack surface: Host header / AllowedHostsMiddleware / Host / AllowedHostsMiddleware.__call__
Patched: 2.22.0 — apply immediately
Plan: 1) Audit SBOM/dependencies, 2) Stage→prod upgrade, 3) Add WAF/proxy monitoring on affected endpoints, 4) Hunt IOCs in logs.
Refs: see the GHSA / vendor advisory / patched release linked on this page.
A vulnerability (CWE-348) exists in litestar. Attackers reach the vulnerable code path via Host header without authentication.
Check the vendor advisory for the affected versions of litestar. Attack surface: Host header / AllowedHostsMiddleware / Host / AllowedHostsMiddleware.__call__.
Severity: Medium (CVSS 5.9/10). Data can be tampered with by attackers.
Update to 2.22.0.
Until the patch is applied: disable the affected feature, apply WAF rules, or restrict access via network ACLs.
Search webserver/proxy logs for unusual request patterns matching this CVE's known IOCs. Run grep -r 'litestar' . against your dependency files (package-lock.json, requirements.txt, go.sum) to find affected services.
Response actions
Concrete steps and command examples for SOC/SRE teams to execute in order
-
1Identify exposure identify
grep -r 'litestar' . | grep -v node_modulesリポジトリと本番環境の依存ファイル (package-lock.json / requirements.txt / go.sum / Gemfile.lock 等) で
litestarを grep し、稼働しているサービス・バージョンを把握する。 -
2Apply patch patch
Upgrade litestar to 2.22.0ステージング環境で 2.22.0 に上げて回帰テスト → 本番反映。回帰テストはアプリの主要ハッピーパスを含めること。
-
3Post-deployment verification verify
Confirm patched version is live in productionパッチ適用後、ステージングで PoC または同等の悪用パターンを再現して脆弱性が閉じたことを確認。本番ではアクセスログ・WAF でアラート再発が無いか継続監視。
Affected packages
References
- package github.com
- web github.com
- web github.com
- web github.com