Starlet incorrectly prioritizes "Content-Length" over "Transfer-Encoding: chunked" when both headers are present in an HTTP request. Per RFC 7230 3.3.3, Transfer-Encoding must take precedence.
An attacker could exploit this to smuggle malicious HTTP requests via a front-end reverse proxy.
No advisories yet.
Solution
Upgrade to Starlet 0.32 or later.
Workaround
Migrate to Starman 0.4018 or later which has fixed this issue or apply the patch.
Thu, 07 May 2026 17:00:00 +0000
| Type | Values Removed | Values Added |
|---|---|---|
| References |
|
Wed, 06 May 2026 20:30:00 +0000
| Type | Values Removed | Values Added |
|---|---|---|
| CPEs | cpe:2.3:a:kazuho:starlet:*:*:*:*:*:perl:*:* |
Mon, 04 May 2026 16:15:00 +0000
| Type | Values Removed | Values Added |
|---|---|---|
| First Time appeared |
Kazuho
Kazuho starlet |
|
| Vendors & Products |
Kazuho
Kazuho starlet |
Mon, 04 May 2026 14:30:00 +0000
| Type | Values Removed | Values Added |
|---|---|---|
| Metrics |
cvssV3_1
|
Sun, 03 May 2026 05:30:00 +0000
| Type | Values Removed | Values Added |
|---|---|---|
| References |
|
Sun, 03 May 2026 01:15:00 +0000
| Type | Values Removed | Values Added |
|---|---|---|
| Description | Starlet versions through 0.31 for Perl allows HTTP Request Smuggling via Improper Header Precedence. Starlet incorrectly prioritizes "Content-Length" over "Transfer-Encoding: chunked" when both headers are present in an HTTP request. Per RFC 7230 3.3.3, Transfer-Encoding must take precedence. An attacker could exploit this to smuggle malicious HTTP requests via a front-end reverse proxy. | |
| Title | Starlet versions through 0.31 for Perl allows HTTP Request Smuggling via Improper Header Precedence | |
| Weaknesses | CWE-444 | |
| References |
|
Projects
Sign in to view the affected projects.
Status: PUBLISHED
Assigner: CPANSec
Published:
Updated: 2026-05-07T16:45:01.655Z
Reserved: 2026-04-14T11:35:53.644Z
Link: CVE-2026-40561
Updated: 2026-05-03T03:04:55.098Z
Status : Modified
Published: 2026-05-03T01:15:58.390
Modified: 2026-05-07T17:15:58.750
Link: CVE-2026-40561
No data.
OpenCVE Enrichment
Updated: 2026-05-04T16:06:41Z