# CVE-2026-27690: SAP Approuter HTTP request smuggling

Source: https://junglewise.ai/threats/cve-2026-27690-sap-approuter-http-request-smuggling  
Publisher: Junglewise Threat Intelligence, https://junglewise.ai/threats  
Published: 2026-07-14. Updated: 2026-09-25  
License: CC BY 4.0 with a link back

CVE-2026-27690 · Severity: critical · CVSS 9.1 · Published 2026-07-14

SAP Approuter is a critical routing component used in SAP cloud applications to handle incoming HTTP requests and forward them to backend services. An unauthenticated attacker can exploit an HTTP request smuggling vulnerability by sending specially crafted requests that desynchronize how the application and backend servers interpret message boundaries. This can expose sensitive data from other users' responses and cause the service to become unavailable, impacting business continuity and customer trust.

Technologies: [@sap/approuter (npm)](https://junglewise.ai/threats/technologies/sap-approuter). Vendors: [npm](https://junglewise.ai/threats/vendors/npm), [SAP SE](https://junglewise.ai/threats/vendors/sap-se).

## Quick answers

**Is CVE-2026-27690 exploited in the wild?** No. Junglewise Threat Intelligence has no report of CVE-2026-27690 being exploited in the wild.

**How severe is CVE-2026-27690?** Critical severity, with a CVSS score of 9.1, published 14 July 2026.

**Which products and versions are affected?** @sap/approuter (npm) < 20.10.0, SEMVER:introduced=0,fixed=20.10.0; SAP SE Approuter < 20.10.0.

**Is there a fix for CVE-2026-27690?** Yes. @sap/approuter (npm): upgrade to 20.10.0 or later. Junglewise finds every place you run it, drafts the upgrade and applies it once you approve.

**How is CVE-2026-27690 attacked?** It is attacked over the network, in a software library.

**Am I affected by CVE-2026-27690?** Check whether you run @sap/approuter (npm) or SAP SE Approuter at an affected version. Junglewise does that check for you around the clock: connect your code, cloud and domains, and it matches new vulnerabilities like this one against what you actually run and tells you when one reaches you.

## How to fix

- @sap/approuter (npm): upgrade to 20.10.0 or later

  ```sh
  npm install @sap/approuter@20.10.0
  ```


## Technical details

The vulnerability is a classic HTTP request smuggling issue (CWE-444) where SAP Approuter inconsistently interprets malformed or ambiguous HTTP request headers compared to the backend servers it proxies to. An attacker can send a specially crafted request that the Approuter interprets as a single request but the backend interprets differently (or vice versa), causing request-response desynchronization. No authentication is required; the attack is network-accessible. Successful exploitation allows an attacker to read responses intended for other users (confidentiality impact) and potentially disrupt service availability. The vulnerability affects versions of the npm package @sap/approuter prior to 20.10.0, which contains the fix.

## Affected products

- SAP Approuter < 20.10.0

## Identifiers

- CVE-2026-27690
- GHSA-8m85-wqg7-c529

## Timeline

- 2026-07-14: disclosed
- 2026-07-14: patched: Version 20.10.0 released with fix

## References

- [https://api.github.com/users/henrybrink](https://api.github.com/users/henrybrink)
- [https://github.com/henrybrink](https://github.com/henrybrink)
- [https://api.github.com/users/henrybrink/gists%7B/gist_id%7D](https://api.github.com/users/henrybrink/gists%7B/gist_id%7D)
- [https://api.github.com/users/henrybrink/repos](https://api.github.com/users/henrybrink/repos)
- [https://avatars.githubusercontent.com/u/20884220?v=4](https://avatars.githubusercontent.com/u/20884220?v=4)
- [https://api.github.com/users/henrybrink/events%7B/privacy%7D](https://api.github.com/users/henrybrink/events%7B/privacy%7D)

## Related threats

- [SAP Approuter token validation information disclosure](https://junglewise.ai/threats/cve-2026-58230-sap-approuter-token-validation-information-disclosure)
- [SAP Approuter open redirect in OAuth2 login flow](https://junglewise.ai/threats/cve-2026-44745-sap-approuter-open-redirect-in-oauth2-login-flow)
- [SAP Approuter authentication bypass via authorization code injection](https://junglewise.ai/threats/cve-2025-24876-sap-approuter-authentication-bypass-via-authorization-code)