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.
Affected products
| Vendor | Product | Affected | Fixed |
|---|---|---|---|
| KAZUHO | Starlet | ≤ 0.31 | — |
Fixed in Linux distributions
Distributions backport fixes, so the version that fixes this vulnerability differs per release — upgrade to at least the version shown. From the distributions' security trackers and advisories.
Debian
Security tracker ↗| Release | Package | Fixed in | Advisory |
|---|---|---|---|
| Debian 14 | starlet | 0.31-3 | — |
| Debian 13 | starlet | 0.31-2+deb13u1 | — |
| Debian 12 | starlet | No fix yet | — |
Ubuntu
Security tracker ↗| Release | Package | Fixed in | Advisory |
|---|---|---|---|
| Ubuntu 26.10 | starlet | No fix yet | — |
| Ubuntu 26.04 LTS | starlet | No fix yet | — |
| Ubuntu 25.10 | starlet | No fix yet | — |
| Ubuntu 24.04 LTS | starlet | No fix yet | — |
| Ubuntu 22.04 LTS | starlet | No fix yet | — |
Show 3 more (older releases, extended support, other products)Fewer releases
| Release | Package | Fixed in | Advisory |
|---|---|---|---|
| Ubuntu 20.04 LTS | starlet | No fix yet | — |
| Ubuntu 18.04 LTS | starlet | No fix yet | — |
| Ubuntu 16.04 LTS | starlet | No fix yet | — |
Alpine
Security tracker ↗| Release | Package | Fixed in | Advisory |
|---|---|---|---|
| Alpine v3.24 | perl-starlet | 0.32-r0 | — |
| Alpine v3.23 | perl-starlet | 0.32-r0 | — |