### Summary `qs.stringify` with `arrayFormat: 'comma'` throws `TypeError: Cannot convert object to primitive value`…
Summary
Vulnerability reported (CVE-2026-110816). Risk of unauthorized operations or information disclosure. Exploitable via qs.stringify. Mitigation: upgrade to 6.16.1 or later.
Original description
The description as published by the source.
Summary
qs.stringify with arrayFormat: 'comma' throws TypeError: Cannot convert object to primitive value when an array element cannot be coerced to a string, such as an object with an own non-callable toString ({ "toString": "x" }) or a null-prototype object. The comma format joins array elements with Array.prototype.join and, under encodeValuesOnly, first passes each element through String() in utils.encode; neither guards against an element whose string coercion fails.
Details
In lib/stringify.js, the comma branch collapses the array with obj.join(','). For an element whose own toString is not callable, ToPrimitive skips it, falls through to Object.prototype.valueOf (which returns the object itself), and throws. Under encodeValuesOnly: true, the same element first reaches String(str) in utils.encode (lib/utils.js) and throws there. Nested arrays ({ "a": [[{ "toString": "x" }]] }) throw the same way, through Array.prototype.toString. The indices, brackets, and repeat formats walk into object elements instead of coercing them, and are not affected.
Such elements can come from untrusted input. JSON.parse produces { "a": [{ "toString": "x" }] } with no qs option involved. qs.parse("a[0][toString]=x", { allowPrototypes: true }) keeps the toString key, and qs.parse("a[][b]=c", { plainObjects: true }) produces a null-prototype element; the default parse options drop toString and produce ordinary objects, which…
Source: NIST National Vulnerability Database NVD
Auto-generated summary
Assembled by SecPulse from the source data (CVSS, CWE, affected versions) using templates — no AI involved. Check the original description and references below for exact details.
A vulnerability tracked as CVE-2026-110816 has been found.
Attackers can target a specific entry point like qs.stringify over the network to misuse the product.
Risk of unauthorized operations or information disclosure. CVSS score: 5.3/10.
What to do: upgrade the affected software to 6.16.1 or later.
If unsure, ask your IT team or search "CVE-2026-110816" on the vendor's site.
CVE-2026-110816 — CWE-248 / CVSS v3 5.3
Attack vector: remote (network-reachable) / unauthenticated / no user interaction
Attack surface: qs.stringify / toString / Array.prototype.join / encodeValuesOnly
Patched: 6.16.1 — apply immediately
Plan: 1) Audit SBOM/dependencies, 2) Stage→prod upgrade, 3) Add WAF/proxy monitoring on affected endpoints, 4) Hunt IOCs in logs.
Refs: see the GHSA / vendor advisory / patched release linked on this page.
A vulnerability (CWE-248) has been reported. Attackers reach the vulnerable code path via qs.stringify without authentication.
Check the vendor advisory for the affected versions. Attack surface: qs.stringify / toString / Array.prototype.join / encodeValuesOnly.
Severity: Medium (CVSS 5.3/10). Risk of unauthorized operations or information disclosure.
Update to 6.16.1.
Until the patch is applied: disable the affected feature, apply WAF rules, or restrict access via network ACLs.
Search webserver/proxy logs for unusual request patterns matching this CVE's known IOCs. Audit SBOM/dependencies to find affected services.
Response actions
Concrete steps and command examples for SOC/SRE teams to execute in order
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1Identify exposure identify
Audit SBOM/dependencies for affected components.資産台帳・SBOM・依存マニフェストで影響コンポーネントを特定する。
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2Apply patch patch
Upgrade to 6.16.1ステージング環境で 6.16.1 に上げて回帰テスト → 本番反映。回帰テストはアプリの主要ハッピーパスを含めること。
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3Post-deployment verification verify
Confirm patched version is live in productionパッチ適用後、ステージングで PoC または同等の悪用パターンを再現して脆弱性が閉じたことを確認。本番ではアクセスログ・WAF でアラート再発が無いか継続監視。
Fix status by distribution
Fixed packages published by each distribution for this CVE
- Debian DEBIAN-CVE-2026-110816 node-qs
- Ubuntu UBUNTU-CVE-2026-110816 node-qs
References
- REDHAT Red Hat
- web github.com
- web github.com