Access control filter bypass allows unauthorised access to APIs
Not confirmed exploited. 1 of 8 rule sources name it. Our CRS test: not blocked.
A vulnerability in the N-central internal API access control filter allows unauthorised access to internal APIs. This is fixed in N-central 2026.3 HF3 and 2026.4
Edge coverage
Claimed by vendorsAsk Vigil
AI · answers from this pageWorkers AI (Llama 3.3). Can be wrong: check the cited source.
Severity, decoded
CVSS 4.0Exploitable over the network, with no privileges and no user interaction, leading to low impact on confidentiality.
How the score is built
- Attack vectorAn attacker can reach it over the internet; no access to your network needed.Network
- Attack complexityNo built-in defences have to be bypassed; the attack works reliably.Low
- Attack requirementsThe attack works without any special deployment or timing conditions.None
- Privileges requiredNo account or login is needed.None
- User interactionNo one has to click or open anything; the attack works on its own.None
- Confidentiality impact (vulnerable system)An attacker can read some data, but has no control over what they get.Low
- Integrity impact (vulnerable system)Data cannot be changed by the attacker.None
- Availability impact (vulnerable system)The component keeps working normally.None
- Confidentiality impact (other systems)Other systems' data is not exposed.None
- Integrity impact (other systems)Other systems' data cannot be changed.None
- Availability impact (other systems)Other systems keep working normally.None
CVSS:4.0/AV:N/AC:L/AT:N/PR:N/UI:N/VC:L/VI:N/VA:N/SC:N/SI:N/SA:NCISA has seen no public exploit and no attacks.
Attackers can script the attack end to end and hit many targets at once.
A successful attack gives limited control over the affected software or limited access to its data.
Public exploits
1 found- NucleiCVE-2026-86206.yamldetection template, replayed in our lab
Links are to third-party code: never run it outside an isolated lab.
Timeline
- 2026-09-05CVE publishedCVE List
- 2026-10-21F5 ships a ruleN-central Authentication Bypass
- 2026-11-02Our test: OWASP Core Rule Set let it throughparanoia level 1, anomaly threshold 5, default CRS settings
- 2026-11-02Our test: OWASP Core Rule Set let it throughparanoia level 2, anomaly threshold 5, default CRS settings
Vendor statements
QuotedCloudflareWAF Managed Rules
We found no public statement from this vendor naming this CVE. That is not proof of no protection: generic rules may still catch it. Each row gives the rule ID and its default action. The feed starts in January 2025, so older rules are missing.
AWSAWS WAF Managed Rules
We found no public statement from this vendor naming this CVE. That is not proof of no protection: generic rules may still catch it. AWS often describes a vulnerability without naming its CVE (for example "Log4j"). We count only entries that name the CVE, so AWS coverage is understated.
Microsoft AzureFront Door and Application Gateway WAF (DRS)
We found no public statement from this vendor naming this CVE. That is not proof of no protection: generic rules may still catch it. The rule tables name CVEs but carry no dates, so Azure is left out of every time-to-rule figure.
Google CloudCloud Armor preconfigured WAF rules
We found no public statement from this vendor naming this CVE. That is not proof of no protection: generic rules may still catch it. Google names few CVEs: the release notes start in May 2024 and the rules reference lists CVEs without dates. Its cve-canary rules are opt-in.
FastlyNext-Gen WAF virtual patches
The CVE predates the oldest entry in this vendor's public feed, so a rule may exist that we cannot see.
F5Attack signatures (Distributed Cloud WAF)
First rule 2026-10-21, 46 days after the CVE was published.
Added: signature 200013233 "N-central Authentication Bypass" (Authentication/Authorization Attacks, risk Medium), systems: Java Servlets/JSP. References: CVE-2026-86206, CVE-2026-86207.
AkamaiApp & API Protector (Adaptive Security Engine)
This vendor publishes no machine-readable rule changelog we can check.
OWASP CRSCore Rule Set (open source, used inside many WAFs)
We found no public statement from this vendor naming this CVE. That is not proof of no protection: generic rules may still catch it. CRS rarely names CVEs: it relies on generic detections. Our own lab measures what it actually blocks.
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