CVE-2026-56018

JavaScript::Minifier::XS versions before 0.16 for Perl leak memory on every call to minify(), allowing unbounded memory growth. In JsMinify (XS.xs) the cleanup frees only the NodeSet structures and never the per-token contents buffers allocated in JsSetNodeContents; JsDiscardNode unlinks nodes without freeing their contents. Each token's contents buffer is therefore leaked on every call, and the two early returns taken when the node list is empty leak the whole NodeSet. A long-lived process that minifies repeatedly, such as an asset pipeline or a server-side minifier endpoint, grows in memory without bound until it exhausts available memory and is killed, 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://github.com/bleargh45/JavaScript-Minifier-XS/issues/10
https://metacpan.org/release/GTERMARS/JavaScript-Minifier-XS-0.16/changes
http://www.openwall.com/lists/oss-security/2026/06/29/17

Configurations

No configuration.

History

29 Jun 2026, 23:16

Type	Values Removed	Values Added
References		() http://www.openwall.com/lists/oss-security/2026/06/29/17 -

29 Jun 2026, 21:16

Type	Values Removed	Values Added
CVSS	v2 : ~~unknown~~ v3 : ~~unknown~~	v2 : unknown v3 : 7.5

29 Jun 2026, 20:17

Type	Values Removed	Values Added
New CVE

Information

Published : 2026-06-29 20:17

Updated : 2026-06-30 14:11

NVD link : CVE-2026-56018

Mitre link : CVE-2026-56018

CVE.ORG link : CVE-2026-56018

JSON object : View

Products Affected

No product.

CWE

CWE-400

Uncontrolled Resource Consumption

CWE-401

Missing Release of Memory after Effective Lifetime

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