CPANSA-JavaScript-Minifier-XS-2026-56017: JavaScript-Minifier-XS vulnerability
| Publisher | giterlizzi | Document category | csaf_security_advisory |
|---|---|---|---|
| Initial release date | 2026-06-29T00:00:00 | Engine | CSAF Perl Toolkit 0.26 |
| Current release date | 2026-06-29T00:00:00 | Build Date | |
| Current version | 1 | Status | final |
| CVSS v3.1 Base Score | 7.5 | Severity | |
| Original language | Language | en | |
| Also referred to | |||
Vulnerability Description
JavaScript::Minifier::XS versions before 0.16 for Perl crash with a NULL pointer dereference when the first meaningful token of the input is a slash. The regexp versus division disambiguator in JsTokenizeString (XS.xs) inspects the previous token's last byte to choose between a regexp literal and a division operator. When a slash is the first meaningful token, with the start of input or only whitespace and comments before it, there is no valid preceding token: the walk back over whitespace and comment nodes runs off the head of the node list to NULL, and the byte lookup reads through a NULL contents pointer at an underflowed length index. The following identifier check dereferences the same NULL pointer. The crash is reachable through the public minify() API, so input as small as a single slash byte crashes the calling process. A service that minifies untrusted or third-party JavaScript can be crashed by a remote request, causing denial of service.
Vulnerabilities
CVE-2026-56017
Vulnerability DescriptionJavaScript::Minifier::XS versions before 0.16 for Perl crash with a NULL pointer dereference when the first meaningful token of the input is a slash.
The regexp versus division disambiguator in JsTokenizeString (XS.xs) inspects the previous token's last byte to choose between a regexp literal and a division operator. When a slash is the first meaningful token, with the start of input or only whitespace and comments before it, there is no valid preceding token: the walk back over whitespace and comment nodes runs off the head of the node list to NULL, and the byte lookup reads through a NULL contents pointer at an underflowed length index. The following identifier check dereferences the same NULL pointer.
The crash is reachable through the public minify() API, so input as small as a single slash byte crashes the calling process. A service that minifies untrusted or third-party JavaScript can be crashed by a remote request, causing denial of service.
| Weakness | CWE-125 : Out-of-bounds Read |
|---|
Product status
Known affected
| Product | Score | ||||||||
|---|---|---|---|---|---|---|---|---|---|
| JavaScript-Minifier-XS less than 0.16 |
|
Fixed
- JavaScript-Minifier-XS greater than or equal 0.16
giterlizzi
Namespace: https://github.com/giterlizzi/
gdt@cpan.org
References
- CPANSA-JavaScript-Minifier-XS-2026-56017 JSON self
https://raw.githubusercontent.com/giterlizzi/perl-CPANSA-CSAF/develop/csaf/white/2026/cpansa-javascript-minifier-xs-2026-56017.json - https://metacpan.org/release/GTERMARS/JavaScript-Minifier-XS-0.16/changes external
https://metacpan.org/release/GTERMARS/JavaScript-Minifier-XS-0.16/changes - http://www.openwall.com/lists/oss-security/2026/06/29/16 external
http://www.openwall.com/lists/oss-security/2026/06/29/16 - CVE-2026-56017 (NVD) external
https://nvd.nist.gov/vuln/detail/CVE-2026-56017
Revision history
| Version | Date of the revision | Summary of the revision |
|---|---|---|
| 1 | Mon Jun 29 00:00:00 2026 | First release |
Sharing rules
TLP:WHITE
For the TLP version see: https://www.first.org/tlp/