CVE-2026-115866: Starlet versions from 0.20 before 0.33 for Perl allow CPU exhaustion via regular expression
Source GCVE Database
Not known to be exploited : upgrade to 0.33 soon.
Data as of 30 Oct 2026, 17:04 UTC
Rated High by Threat Radar's AI analysis · CVSS not yet scored by NVD
Thin evidence
One scorer or none- Patch
- Available – fixed in 0.33
Exploitation evidence
Disclosed: evidence found.
CVE published 30 Oct 2026
Detectable: no evidence on record.
No public nuclei template indexed
Weaponized: no evidence on record.
No public exploit code indexed in Metasploit or Exploit-DB
Exploited in the wildExploited: no evidence on record.
Not in CISA KEV and no source reports exploitation
Observed by OffSeq MirageSeen by Mirage: no evidence on record.
No attack traffic recorded by OffSeq Mirage sensors
A missing step is not evidence of safety. Sources: cve.org (opens in a new tab), the Metasploit, Exploit-DB and nuclei-templates index as of 30 Oct 2026.
What to do
Upgrade Starlet (Perl module) to 0.33.
Affected software
| Product | Affected | Fixed in |
|---|---|---|
| Starlet | Affected
| Fixed in
|
CPANStarletpkg:cpan/StarletOther threats | Affected
| Fixed in
|
Check your own hosts for these packages with threat-finder (opens in a new tab), our free open-source scanner.
AI-suggested
If you cannot patch yet, consider limiting the size of chunked requests or deploying rate limiting to mitigate potential CPU exhaustion.
Description
Starlet versions from 0.20 up to but not including 0.33 for Perl contain a vulnerability that allows CPU exhaustion via regular expression backtracking when decoding chunked request bodies. The flaw arises because the chunk-size line matching can cause the regex engine to retry matches quadratically with the length of the input, and there is no limit on the length of the run. A remote attacker can exploit this by sending a specially crafted 128 KiB request, causing a worker to consume about a minute of CPU time.