CVE-2026-32701 is a high-severity (CVSS 7.5) CWE-843 vulnerability in @builder.io/qwik-city. A fix is available for @builder.io/qwik-city — see the affected versions and patch details below.
Qwik has array method pollution in FormData processing, allowing type confusion and DoS
Exploitation Status
No confirmed exploitation observed yet
- CISA assesses this as automatable — exploitation doesn’t require manual, per-target effort, which raises the odds of mass scanning and opportunistic attacks.
- CISA’s own triage has not observed active exploitation or public proof-of-concept code for this CVE as of its last assessment.
Exploitation and automatability from CISA’s SSVC triage for CVE-2026-32701.
EPSS Exploitation Probability
EPSS (Exploit Prediction Scoring System) is a daily probability model maintained by FIRST.org. It estimates the likelihood a CVE will be exploited in production environments within the next 30 days, derived from real-world threat intelligence signals.
How urgent is this, really
CVE-2026-32701 plotted by exploitation likelihood (EPSS) against impact (CVSS). The shaded corner — EPSS 50%+ and CVSS 7.0+ — is where this CVE doesn't sit, though severity or exploitability alone can still warrant action.
Where this sits among everything scored
Of 377,636 CVEs with a current EPSS score, this one falls in the < 10% band (highlighted). Real counts from FIRST.org, not a sample — log-scaled since the landscape is heavily right-skewed.
Real-World Exposure
How broadly this vulnerability is actually deployed: weekly install volume shows current usage, and reverse-dependency count shows how many other packages break if it stays unpatched.
@builder.io/qwik-citynpmDescription
Summary
Qwik City improperly inferred arrays from dotted form field names during FormData parsing. By submitting mixed array-index and object-property keys for the same path, an attacker could cause user-controlled properties to be written onto values that application code expected to be arrays.
Description
When processing application/x-www-form-urlencoded or multipart/form-data requests, Qwik City converted dotted field names such as items.0 and items.1 into nested structures. If a path was interpreted as an array, additional attacker-controlled keys on the same path, such as items.toString, items.push, items.valueOf, or items.length, could alter the resulting server-side value in unexpected ways.
Applications that assumed these parsed values were safe arrays could be affected. Depending on application behavior, this could lead to request handling failures, denial of service through malformed array state or oversized lengths, and type confusion in downstream code.
This issue affects form parsing in Qwik City request handling. It does not require authentication if the vulnerable route is publicly reachable.
Impact
An attacker can send crafted form submissions that cause parsed input to differ from the application’s expected shape. Possible outcomes include:
- Triggering runtime errors when application code calls array methods on attacker-influenced values
- Inflating array length or otherwise creating malformed structures that increase server work or memory use
- Causing type confusion in application logic that trusts parsed form data to be a normal array
There is no direct evidence that this issue enables confidentiality or integrity impact by itself; the primary risk is denial of service and application instability.
Patched Versions
Patched in 1.19.2.
Workarounds
Until patched, avoid trusting parsed form data to be a well-formed array when using dotted field names, and validate or normalize action input before using array methods or relying on array shape.
Affected Packages
| Ecosystem | Package | Vulnerable range | Fix |
|---|---|---|---|
| 📦npm | @builder.io/qwik-city | all versions | 1.19.2npm install @builder.io/qwik-city@1.19.2 |
Detection & mitigation playbook
Open-source dependencyDetect
Scan your dependency tree (package-lock.json, pnpm-lock.yaml, requirements.txt, go.sum, etc.) for @builder.io/qwik-city, including transitive dependencies — a direct dependency you never call can still pull in a vulnerable version.
Fix
Update @builder.io/qwik-city to 1.19.2 or later, then make sure no transitive (indirect) dependency still pins the vulnerable range — O3 confirms CVE-2026-32701 is resolved across your whole dependency graph.
Workarounds
If you can't upgrade right away: gate or disable the affected feature, validate untrusted input at the boundary, and avoid passing attacker-controlled data into the vulnerable path. O3's runtime protection blocks exploitation in production as an interim safeguard until the upgrade lands.
How O3 protects you
O3 Security's impact-aware SCA analyses which vulnerable code paths your application actually calls, so a match like CVE-2026-32701 can be triaged on real exposure rather than presence alone.
Tailored to CVE-2026-32701. Runtime protection reduces exposure until a permanent patch is applied and verified — it complements patching, it doesn't replace it.
Frequently Asked Questions
Is CVE-2026-32701 in your dependencies?
O3 Security finds CVE-2026-32701 across npm dependencies, including transitive ones, and its impact-aware SCA ranks findings by whether your code actually calls the vulnerable path.