CVE-2026-56018: CWE-401 Missing Release of Memory after Effective Lifetime in GTERMARS JavaScript::Minifier::XS
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.
AI Analysis
Technical Summary
CVE-2026-56018 is a memory leak vulnerability in JavaScript::Minifier::XS prior to version 0.16. The vulnerability occurs because the cleanup process only frees NodeSet structures but neglects to free the per-token contents buffers allocated in JsSetNodeContents. Additionally, nodes are unlinked without freeing their contents, resulting in leaked memory on every call to minify(). This leads to unbounded memory growth in long-lived processes that repeatedly invoke minification, potentially causing denial of service due to memory exhaustion.
Potential Impact
The vulnerability causes unbounded memory growth in affected versions of JavaScript::Minifier::XS when minify() is called repeatedly. This can lead to exhaustion of system memory and termination of the process, resulting in denial of service. There is no impact on confidentiality or integrity reported.
Mitigation Recommendations
Patch status is not yet confirmed — check the vendor advisory for current remediation guidance. Until a fix is available, avoid running long-lived processes that repeatedly call minify() on affected versions or implement external memory management controls to limit resource exhaustion.
CVE-2026-56018: CWE-401 Missing Release of Memory after Effective Lifetime in GTERMARS JavaScript::Minifier::XS
Description
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 v3.1
Score 7.5high
Affected software
pkg:github/JavaScript-Minifier-XSRun on your own infrastructure? Check whether these packages are installed with threat-finder — our free open-source scanner.
AI-Powered Analysis
Machine-generated threat intelligence
Technical Analysis
CVE-2026-56018 is a memory leak vulnerability in JavaScript::Minifier::XS prior to version 0.16. The vulnerability occurs because the cleanup process only frees NodeSet structures but neglects to free the per-token contents buffers allocated in JsSetNodeContents. Additionally, nodes are unlinked without freeing their contents, resulting in leaked memory on every call to minify(). This leads to unbounded memory growth in long-lived processes that repeatedly invoke minification, potentially causing denial of service due to memory exhaustion.
Potential Impact
The vulnerability causes unbounded memory growth in affected versions of JavaScript::Minifier::XS when minify() is called repeatedly. This can lead to exhaustion of system memory and termination of the process, resulting in denial of service. There is no impact on confidentiality or integrity reported.
Mitigation Recommendations
Patch status is not yet confirmed — check the vendor advisory for current remediation guidance. Until a fix is available, avoid running long-lived processes that repeatedly call minify() on affected versions or implement external memory management controls to limit resource exhaustion.
Technical Details
- Data Version
- 5.2
- Assigner Short Name
- CPANSec
- Date Reserved
- 2026-06-18T11:27:09.117Z
- Cvss Version
- null
- State
- PUBLISHED
- Remediation Level
- null
Threat ID: 6a42d3d527e9c7971972d1c2
Added to database: 06/29/2026, 20:21:41 UTC
Last enriched: 07/06/2026, 22:48:30 UTC
Last updated: 08/13/2026, 00:41:13 UTC
Views: 90
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