How should we interpret CVSS severity scores?

CVSS estimates technical severity, but it does not automatically equal business risk. Prioritize using context like internet exposure, asset criticality, known exploitation, and whether compensating controls exist. A Medium CVSS on an exposed production system can be more urgent than a Critical on an isolated non-production host.

Vulnerability Database

Q: What is a Vulnerability (CVE) and why does it matter?

A security vulnerability is a weakness in software, hardware, or configuration that can be exploited to compromise confidentiality, integrity, or availability. Many vulnerabilities are tracked as CVEs (Common Vulnerabilities and Exposures), which provide a standardized identifier so teams can coordinate patching, mitigation, and risk assessment across tools and vendors.

Q: What's the difference between a vulnerability, an exploit, and a zero-day?

A vulnerability is the underlying weakness. An exploit is the method or code used to take advantage of it. A zero-day is a vulnerability that is unknown to the vendor or has no publicly available fix when attackers begin using it. Risk increases sharply when exploitation becomes reliable or widespread.

Q: Why do vulnerabilities keep reappearing in our environment?

Recurring findings usually come from incomplete asset discovery, inconsistent patch management, inherited images, and configuration drift. In modern environments, you also need to watch the software supply chain: dependencies, containers, build pipelines, and third-party services can reintroduce the same weakness even after you patch a single host.

Q: How do we prioritize remediation without burning out the team?

Use a repeatable triage model: focus first on externally exposed assets, high-value systems (identity, VPN, email, production), vulnerabilities with known exploits, and issues that enable remote code execution or privilege escalation. Then enforce patch SLAs and track progress so remediation is steady, not reactive.

Q: How can SynScan help reduce vulnerability risk over time?

SynScan combines attack surface monitoring and continuous security auditing to keep your inventory current, flag high-impact vulnerabilities early, and help you turn raw findings into a practical remediation plan.

383,371

Total vulnerabilities in the database

CVE-2026-82562 — @types / qs

Allocation of Resources Without Limits or Throttling

Summary

When qs.parse is called with comma: true and throwOnLimitExceeded: true, a comma-separated value under a bracket-push key (a[]=1,2,3,4) is split into an array without being compared against arrayLimit, while the same value under a flat key (a=1,2,3,4), an indexed key (a[0]=), a nested key (a[b]=), or a dotted key (a.b= with allowDots) throws the documented RangeError. A single parameter such as a[]=1,2,2,... therefore produces an inner array of arbitrary length even though the caller opted into the hard limit. This is the []= key form that the fix for CVE-2026-2391 (qs 6.14.2) did not cover.

Details

In lib/parse.js, a comma-separated value under a []= key is split and then wrapped as a single nested element (val = [val], so that each a[]=x,y group counts as one element of the outer array). The arrayLimit check that 6.14.2 added for comma values runs after that wrap, so for []= parts it only ever saw the wrapper of length 1. 6.15.3 added a pre-split comma count so that an oversized value throws before it is allocated, but gated it on an isFlatArrayValue flag that parseValues set to false for any part containing []=, and did not pass it for object-valued input, so the gap remained.

PoC




var qs = require(&#039;qs&#039;);



var options = { comma: true, arrayLimit: 3, throwOnLimitExceeded: true };



qs.parse(&#039;a=1,2,3,4&#039;, options);   // RangeError: Array limit exceeded. Only 3 elements allowed in an array.



qs.parse(&#039;a[]=1,2,3,4&#039;, options); // { a: [ [ &#039;1&#039;, &#039;2&#039;, &#039;3&#039;, &#039;4&#039; ] ] }  (no throw)



qs.parse(&#039;a[]=&#039; + &#039;1,&#039;.repeat(1000000) + &#039;1&#039;, { comma: true, arrayLimit: 20, throwOnLimitExceeded: true });



// no throw; a 1,000,001-element inner array is allocated

Fix

lib/parse.js, applied in 8859c37 on main and released as v6.16.0: the isFlatArrayValue gate is removed, so every comma-split value is counted against arrayLimit before splitting regardless of key form. An in-limit group under a[]= still counts as one element of the outer array, and the default (throwOnLimitExceeded: false) path is unchanged.

Affected versions

>=6.14.2 <6.16.0, fixed in v6.16.0.

v6.14.2 introduced arrayLimit enforcement for comma values (the fix for CVE-2026-2391) but only for values not under a []= key, and every release from v6.14.2 through v6.15.3 has the same gap. v6.14.0 and v6.14.1, where throwOnLimitExceeded exists but does not apply to any comma form, are covered by CVE-2026-2391 rather than this record. Earlier lines (6.7.x through 6.13.x) have comma but no throwOnLimitExceeded, so there is no hard cap on any comma path to bypass; releases before 6.7.0 have no comma option.

Impact

An unauthenticated attacker who can reach an application that parses untrusted query strings or urlencoded bodies with both comma: true and throwOnLimitExceeded: true (both non-default) can bypass the configured limit with a single a[]= parameter and force the parser to allocate an array proportional to the request size. The cost is strictly linear in the attacker-supplied bytes (about 0.1 microseconds and 6 to 7 retained bytes per input byte; the same out-of-memory threshold as the documented default throwOnLimitExceeded: false path), so a transport-layer request or body size limit bounds it completely (and node's default maximum HTTP header size of 16 KB already bounds the request line, so multi-megabyte payloads need a body parser). The impact is that an opt-in hard limit fails open on one key spelling, not unbounded allocation from a small input.

Published: Aug 30, 2026
Updated: Sep 13, 2026
CVE: CVE-2026-82562
GHSA: GHSA-x5fp-wj9c-mxmx
Severity: Medium
Exploit:
CISA KEV:

CVSS v3:

Severity: Low
Score: 3.7
AV:N/AC:H/PR:N/UI:N/S:U/C:N/I:N/A:L

CWEs:

CWE-770

Affected Software
References

Software	Affected versions
@types / qs	`>= 6.14.2, < 6.16.0`

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Frequently Asked Questions

What is a Vulnerability (CVE) and why does it matter?

A security vulnerability is a weakness in software, hardware, or configuration that can be exploited to compromise confidentiality, integrity, or availability. Many vulnerabilities are tracked as CVEs (Common Vulnerabilities and Exposures), which provide a standardized identifier so teams can coordinate patching, mitigation, and risk assessment across tools and vendors.

CVSS (Common Vulnerability Scoring System) estimates technical severity, but it doesn't automatically equal business risk. Prioritize using context like internet exposure, affected asset criticality, known exploitation (proof-of-concept or in-the-wild), and whether compensating controls exist. A "Medium" CVSS on an exposed, production system can be more urgent than a "Critical" on an isolated, non-production host.

A vulnerability is the underlying weakness. An exploit is the method or code used to take advantage of it. A zero-day is a vulnerability that is unknown to the vendor or has no publicly available fix when attackers begin using it. In practice, risk increases sharply when exploitation becomes reliable or widespread.

Recurring findings usually come from incomplete Asset Discovery, inconsistent patch management, inherited images, and configuration drift. In modern environments, you also need to watch the software supply chain: dependencies, containers, build pipelines, and third-party services can reintroduce the same weakness even after you patch a single host. Unknown or unmanaged assets (often called Shadow IT) are a common reason the same issues resurface.

Use a simple, repeatable triage model: focus first on externally exposed assets, high-value systems (identity, VPN, email, production), vulnerabilities with known exploits, and issues that enable remote code execution or privilege escalation. Then enforce patch SLAs and track progress using consistent metrics so remediation is steady, not reactive.

SynScan combines attack surface monitoring and continuous security auditing to keep your inventory current, flag high-impact vulnerabilities early, and help you turn raw findings into a practical remediation plan.