Starlet versions from 0.20 before 0.33 for Perl allow CPU exhaustion via regular expression backtracking when decoding chunked request bodies
Summary
| CVE | CVE-2026-115866 |
|---|---|
| State | PUBLISHED |
| Assigner | CPANSec |
| Source Priority | CVE Program / NVD first with legacy fallback |
| Published | 2026-10-30 13:18:31 UTC |
| Updated | 2026-10-30 17:13:54 UTC |
| Description | Starlet versions from 0.20 before 0.33 for Perl allow CPU exhaustion via regular expression backtracking when decoding chunked request bodies. A chunk-size line is matched as a run of hex digits, then .* and a CRLF. A run followed by a bare LF and then a CRLF can never match, and the engine retries the match once for each digit, so the time taken grows with the square of the run length. Nothing limits the length of the run, which can span several reads. A remote attacker can occupy a worker for about a minute of CPU time with one 128 KiB request, before the application is called. |
Risk And Classification
EPSS: 0.002390000 probability, percentile 0.150750000 (date 2026-11-01)
Problem Types: CWE-1333 | CWE-1333 CWE-1333 Inefficient Regular Expression Complexity
There are no known software configurations currently associated with this CVE in NVD or the CVE Program record.
References
| Reference | Source | Link | Tags |
|---|---|---|---|
| metacpan.org/release/KAZUHO/Starlet-0.33/changes | 9b29abf9-4ab0-4765-b253-1875cd9b441e | metacpan.org | |
| github.com/kazuho/Starlet/commit/229ea56b3b50028e2a644156317e8d0e7cf68a1... | 9b29abf9-4ab0-4765-b253-1875cd9b441e | github.com | |
| CVE Program record | CVE.ORG | www.cve.org | canonical |
| NVD vulnerability detail | NVD | nvd.nist.gov | canonical, analysis |
No vendor comments have been submitted for this CVE.
Additional Advisory Data
Solutions
CNA: Upgrade to Starlet 0.33 or later.
There are currently no legacy QID mappings associated with this CVE.