CVE-2026-56017

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.

CVSS v3 7.5 HIGH

7.5^/10

CVSS v3 : HIGH

Vector :

Exploitability : 3.9 / Impact : 3.6

Attack Vector NETWORK

Attack Complexity LOW

Privileges Required NONE

User Interaction NONE

Confidentiality Impact NONE

Integrity Impact NONE

Availability Impact HIGH

Scope UNCHANGED

References

Link	Resource
https://metacpan.org/release/GTERMARS/JavaScript-Minifier-XS-0.16/changes
http://www.openwall.com/lists/oss-security/2026/06/29/16

Configurations

No configuration.

History

No history.

Information

Published : 2026-06-29 20:17

Updated : 2026-06-30 14:11

NVD link : CVE-2026-56017

Mitre link : CVE-2026-56017

CVE.ORG link : CVE-2026-56017

JSON object : View

Products Affected

No product.

CWE

CWE-125

Out-of-bounds Read

CWE-476

NULL Pointer Dereference

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