What it is
CVE-2026-27971 is an unauthenticated vulnerability affecting QwikDev qwik. Qwik is a performance focused javascript framework. qwik <=1.19.0 is vulnerable to RCE due to an unsafe deserialization vulnerability in the...
Vulnerability report
Active exploitation observed
Confirmed confidence
Not in CISA KEV
CVE-2026-27971
qwik Affected by unauthenticated RCE Remote Code Execution
QwikDev / qwik · affected before 1.19.1
- Severity
- CVSS 9.2 · Critical
- Confidence
- Confirmed
- Exploit status
- Observed in sensors
- EPSS
- 5.4%
- First observed
- 14 Jul 2026
- Last observed
- 22 Aug 2026
Decision summary
What security teams need to know first
Direct answers before the deeper technical record.
Is it exploited?
Yes. Previdian sensors observed exploitation attempts with confirmed confidence.
Who is affected?
QwikDev / qwik affected before 1.19.1.
What should we do?
Patch immediately, validate internet-facing exposure, and monitor for matching requests.
Overview
Qwik is a performance focused javascript framework
Qwik is a performance focused javascript framework. qwik <=1.19.0 is vulnerable to RCE due to an unsafe deserialization vulnerability in the server$ RPC mechanism that allows any unauthenticated user to execute arbitrary code on the server with a single HTTP request.
Affects any deployment where require() is available at runtime. This vulnerability is fixed in 1.19.1.
Vendor
Product
Affected
Status
QwikDev
qwik
Before 1.19.1
Affected
- Published
- 03 Mar 2026
- Exploitation Reported
- 14 Jul 2026
- Attack vector
- Remote
- Complexity
- Low
- Privileges
- None
- User interaction
- None
Tags
nuclei_scanner
CVE References
- CVE Record CVE.org · CVE Record https://www.cve.org/CVERecord?id=CVE-2026-27971
- https://github.com/QwikDev/qwik/security/advisories/GHSA-p9x5-jp3h-96mm github.com · CVE Record https://github.com/QwikDev/qwik/security/advisories/GHSA-p9x5-jp3h-96mm
Exploitation evidence
Why Previdian marks this CVE as exploited
Third-party attestation and first-party sensor observation are shown separately so teams can judge the evidence chain.
Exploited in the wild
Previdian
Independent exploitation attestation added to the Previdian record.
Active exploitation observed
Previdian sensor
First-party sensor telemetry confirms matching exploitation attempts.
Proof of concept available
Nuclei Templates
Public scanner or PoC coverage increases practical exploitability.
Known exploited vulnerability sources
Per-source evidence links for KEV attestations are available through the Previdian Pro API.
Learn about Pro API access| Source | Added |
|---|---|
| Previdian First | 2026-08-22 16:14 UTC |
Operational indicators for this CVE are listed under Detection.
Sensor telemetry
First-party evidence of exploitation activity
Aggregate observations show the scale, recency, and distribution of activity without overstating sparse data.
4
Attempts observed
4
Unique attacker IPs
4
Attacker countries
HK · JP · NL · US
4
Sensors observed
Exploitation attempts over the last 44 days
Daily events observed by Previdian sensors
Updated 25 Aug 2026
13 Jul
22 Jul
31 Jul
9 Aug
25 Aug
First observed 14 Jul 2026 · Last observed 22 Aug 2026
Pro adds sensor region and window summaries. Enterprise adds raw IPs, paths, User-Agents, and payloads.
Detection
Operational artifacts and observed signals
Make the evidence actionable in scanner, SOC, and edge-control workflows.
Observed signals
- Request targets
- 1
- User-Agents
- 4
Raw values available in Pro and Enterprise.
Scanner coverage
Nuclei template detected 01 Jun 2026.
View Nuclei template (opens in new tab)Virtual patch status
No Previdian virtual patch is currently available. Future rules ship for ModSecurity, Cloudflare, and AWS WAF.
Learn about virtual patches →Attacker IP Indicators
Attacker IP indicators observed · available in Pro and Enterprise.
Sensor-derived attacker IP indicators are available to Pro and Enterprise accounts under Detection and through the Pro API.
Learn about Pro API accessScanner Artifacts
Scanner and exploit-framework references linked to this CVE.
| Scanner | Reference | Detected |
|---|---|---|
| Nuclei | https://github.com/projectdiscovery/nuclei-templates/blob/main/http/cves/2026/CVE-2026-27971.yaml | 01 Jun 2026 |
Risk and context
Severity, weaknesses, and research context
CVSS v4.0
9.2
Critical
CVSS:4.0/AV:N/AC:L/AT:P/PR:N/UI:N/VC:H/VI:H/VA:H/SC:N/SI:N/SA:N
EPSS
5.4%
Weaknesses
All CVSS Scores
CVSS v4.0
9.2
Critical
CVSS:4.0/AV:N/AC:L/AT:P/PR:N/UI:N/VC:H/VI:H/VA:H/SC:N/SI:N/SA:N
CVSS v3.1
9.8
Critical
CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:H/A:H
Potential Proof of Concepts
These PoCs are unverified and could contain malware. Use at your own risk.
Qwik - Unauthenticated RCE via server$ Deserialization
nuclei · Created Unknown
Timeline
From disclosure to observed exploitation
-
Indicators of compromise added (5)
Indicators of compromise recorded
-
Observed by Previdian sensors
Evidence-backed exploitation signal
-
Public PoC available
Public proof-of-concept code published
-
Nuclei template available
Scanner coverage available
-
CVE published
Vulnerability disclosed publicly
-
CVE ID reserved
Identifier reserved by the CNA
Pro API
Automate this intelligence
Confidence, exploit status, sensor telemetry, PoCs, scanner integrations, mentions, and tags are available programmatically for VM, SOC, and CTI workflows.
- Evidence confidence and provenance
- First-party sensor telemetry
- PoC and scanner references
- Affected versions and enrichment
- Automation-ready JSON delivery
GET /api/v2/pro/kevs/CVE-2026-27971
Free JSON includes basic KEV fields{
"cve_id": "CVE-2026-27971",
"confidence": "Confirmed",
"cvss_score": 9.2,
"cvss_estimated": false,
"epss_score": 0.05416,
"exploit_status": {
"exploited_in_the_wild": true,
"active_exploitation_observed": true
},
"sensor_telemetry": { "attempts": 4, "sensors": 4 }
}Early warning alerts
Get alerts on high-impact exploitation
Receive curator-selected alerts when exploitation activity warrants attention. Each alert includes the evidence and context needed to decide what requires attention now.