# CVE-2026-43870: Apache Thrift path traversal and request splitting in web server

Source: https://junglewise.ai/threats/cve-2026-43870-apache-thrift-path-traversal-and-request-splitting-in-web-server  
Publisher: Junglewise Threat Intelligence, https://junglewise.ai/threats  
Published: 2026-05-05. Updated: 2026-09-25  
License: CC BY 4.0 with a link back

CVE-2026-43870 · Severity: high · CVSS 7.3 · Published 2026-05-05

Apache Thrift is a cross-language RPC framework used by many applications to enable service communication. The Node.js web server component has vulnerabilities that allow attackers to bypass directory restrictions, inject HTTP headers for cache poisoning or session hijacking, and exhaust server resources. Exploitation requires no authentication and impacts service availability and data confidentiality.

Technologies: [Apache Thrift](https://junglewise.ai/threats/technologies/thrift). Vendors: [Apache](https://junglewise.ai/threats/vendors/apache).

## Quick answers

**Is CVE-2026-43870 exploited in the wild?** No. Junglewise Threat Intelligence has no report of CVE-2026-43870 being exploited in the wild.

**How severe is CVE-2026-43870?** High severity, with a CVSS score of 7.3, published 5 May 2026.

**Which products and versions are affected?** Apache Thrift before 0.23.0.

**Is there a fix for CVE-2026-43870?** A patch was published on 2026-04-27: Fixed in version 0.23.0 Junglewise finds every place you run it, drafts the upgrade and applies it once you approve.

**How is CVE-2026-43870 attacked?** It is attacked over the network, in a software library.

**Am I affected by CVE-2026-43870?** Check whether you run Apache Thrift 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.

## Technical details

Apache Thrift's Node.js web_server.js implementation contains multiple distinct vulnerabilities: (1) path traversal via improper pathname validation (CWE-22), (2) HTTP request/response splitting through unsanitized CRLF sequences in HTTP headers, and (3) uncontrolled resource consumption. These issues stem from origin validation errors and insufficient input sanitization in the web server request handling. An unauthenticated remote attacker can exploit these vulnerabilities over the network without user interaction. Successful exploitation enables file access outside intended directories, HTTP header injection for cache poisoning or request smuggling, and denial-of-service via resource exhaustion. The vulnerabilities are fixed in Apache Thrift version 0.23.0 and later.

## Affected products

- Apache Thrift before 0.23.0

## Identifiers

- CVE-2026-43870
- GHSA-526f-jxpj-jmg2

## Timeline

- 2026-05-05: disclosed: Advisory published
- 2026-04-27: patched: Fixed in version 0.23.0

## References

- [https://github.com/apache/thrift/commit/80184ddca4d4f60ac657bd82b2abc47269814f79](https://github.com/apache/thrift/commit/80184ddca4d4f60ac657bd82b2abc47269814f79)
- [https://github.com/apache/thrift](https://github.com/apache/thrift)
- [https://github.com/apache/thrift/releases/tag/v0.23.0](https://github.com/apache/thrift/releases/tag/v0.23.0)
- [https://lists.apache.org/thread/pgtfq44ltc9t63kxcbqmwqzt45pnhqdy](https://lists.apache.org/thread/pgtfq44ltc9t63kxcbqmwqzt45pnhqdy)
- [http://www.openwall.com/lists/oss-security/2026/05/05/4](http://www.openwall.com/lists/oss-security/2026/05/05/4)

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