Question 370
A production hardening ticket was raised after this confirmed observation: The SMTP server expands distribution-list membership for outside requesters, revealing the addresses of employees who are supposed to remain private. Which action best targets the risk?
- Restrict share listing and access through SMB permissions and segmentation
- Restrict SMTP EXPN and directory-list visibility to authorized users
- Protect routing management interfaces and authenticate peer sessions
- Disable anonymous enumeration and review guest or null-session policies
Explanation
Correct Answer
B:A restricted expansion policy preserves legitimate mail flow while avoiding needless disclosure of group membership to external peers. That correction is linked to the fact that SMTP EXPN may reveal distribution-list membership and addresses when the gateway permits expansion to untrusted requesters.
Incorrect Answers
A:Share and NTFS permissions plus network isolation reduce unauthorized resource browsing even when SMB must remain available to staff; this is relevant to a separate SMB share enumeration scenario, rather than the identified exposure; the tested fault instead involves SMTP EXPN group expansion.
C:Restricting management access and securing routing neighbors reduces unwanted disclosure and unauthorized route-policy changes; that safeguard does not directly close the SMTP EXPN group expansion route highlighted by the test.
D:Explicitly limiting unauthenticated SMB and RPC access prevents account and share disclosure while preserving required authenticated service use; the proposed improvement would make sense for SMB null-session exposure but not as the main fix here; the tested fault instead involves SMTP EXPN group expansion.
Question 371
During a documented lab review, an analyst notes: A switch receives thousands of frames with different spoofed source MACs and begins behaving abnormally under table pressure. What mechanism should be recorded?
- MAC address table flooding
- MACsec link encryption
- DHCP starvation
- LLMNR name-resolution poisoning
Explanation
Correct Answer
A:CAM table flooding attempts to exhaust switch learning resources; some switches may flood unknown unicast frames more broadly when entries are unavailable. On affected systems, it is useful to apply switch port security and MAC learning limits; per-port learned-address limits reduce the ability of one physical connection to poison the forwarding table with fictitious sources.
Incorrect Answers
B:MACsec protects Ethernet frames on a local link; it does not replace end-to-end application encryption across routers and other network hops; the events given do not establish this behavior but do support MAC address table flooding.
C:DHCP starvation consumes address leases by presenting many apparent clients so legitimate machines cannot obtain a normal lease; the reported conditions are characteristic of MAC address table flooding, not that path.
D:Link-Local Multicast Name Resolution can resolve names on the local segment without ordinary DNS; spoofed responses can redirect clients to hostile listeners; those prerequisites differ from the MAC address table flooding behavior in the record.
Question 372
The owner asks for a durable safeguard against the issue demonstrated here: A wireless router enables PIN enrollment by default even though employees use an established management system for securely onboarding all approved devices. What is the best response?
- Require PMF on compatible managed wireless networks
- Use spectrum monitoring and resilient channel or coverage planning
- Use a strong random passphrase or move to enterprise authentication
- Enable WPA3-SAE and current firmware without unsafe transition settings
- Use validated enterprise server certificates and rogue-AP detection
- Disable unnecessary WPS PIN enrollment and enforce secure onboarding
Explanation
Correct Answer
F:Removing the vulnerable setup mechanism closes a parallel authentication path that can undermine an otherwise strong WPA2 password. The underlying condition is that some WPS PIN implementations expose an effectively split PIN validation process and weak rate controls, making this enrollment method attackable.
Incorrect Answers
A:Protected management frames reduce spoofed deauthentication and disassociation attacks, though they do not prevent radio-frequency jamming; the exposure here is WPS PIN weakness, which calls for another protective mechanism.
B:RF monitoring identifies interference patterns and alternative coverage or channels restore service without misdiagnosing the outage as a password issue; the action is aimed at wireless jamming; it leaves the central WPS PIN weakness condition unresolved.
C:High-entropy secrets resist offline guesses, while per-user enterprise credentials remove the single shared passphrase from the whole fleet; this is relevant to a separate WPA2-Personal weak passphrase scenario, rather than the identified exposure; the tested fault instead involves WPS PIN weakness.
D:Modern authentication strengthens password exchange, while configuration and software updates address downgrade and implementation risks; the tested weakness is WPS PIN weakness, not the WPA3-SAE authentication configuration addressed here.
E:Clients that verify the authentication server identity are less likely to trust a lookalike AP offering the same SSID; that safeguard does not directly close the WPS PIN weakness route highlighted by the test.
Question 373
The post-assessment action plan cites this evidence: Several employees who regularly browse a trade association forum encounter a newly injected third-party script that redirects them to hostile content. Which corrective measure should be prioritized?
- Verify sensitive requests through a separate trusted communication channel
- Use number matching and phishing-resistant authentication with prompt anomaly alerts
- Display and verify actual destinations before authenticating from QR links
- Apply browser isolation or hardening and monitor third-party script behavior
Explanation
Correct Answer
D:Client-side controls and update hygiene reduce damage from compromised familiar sites that cannot be safely treated as automatically trustworthy. It directly addresses this mechanism: watering-hole attacks compromise a site commonly visited by a target population, delivering malicious content through a trusted browsing habit.
Incorrect Answers
A:Independent confirmation prevents project-specific impersonation from being treated as proof that an email request was authorized; the proposed improvement would make sense for spear phishing but not as the main fix here; the tested fault instead involves watering-hole compromise.
B:Challenge context and stronger factors reduce blind approvals, while alerting and throttling expose the repetitive abuse pattern; the specific root cause belongs to watering-hole compromise, beyond this control's intended scope.
C:Destination validation and approved app-based entry points reduce credential submission to counterfeit sites reached through physical codes; that change targets QR-code phishing, while the confirmed weakness involves watering-hole compromise.
Question 374
The approved test uncovered this weakness: An external guest can retrieve organizational-unit members from a directory server without presenting credentials, despite a policy requiring authenticated directory clients. Which control would reduce the relevant exposure without relying on obscurity?
- Disable anonymous enumeration and review guest or null-session policies
- Require authenticated binds and restrict readable directory attributes
- Use SNMPv3 with authentication, privacy, and management ACLs
- Patch time services and restrict diagnostic control queries
Explanation
Correct Answer
B:Authentication and attribute-level authorization stop unauthenticated collection of membership information while retaining approved application queries. The specific weakness being corrected is that anonymous bind behavior depends on directory configuration; exposing membership attributes enables reconnaissance without granting an application login.
Incorrect Answers
A:Explicitly limiting unauthenticated SMB and RPC access prevents account and share disclosure while preserving required authenticated service use; the required correction concerns anonymous LDAP bind, so this is not the targeted control.
C:SNMPv3 protects management exchanges, while device and network restrictions reduce exposure of sensitive interface and configuration details; the exposure here is anonymous LDAP bind, which calls for another protective mechanism.
D:Current versions and access restrictions prevent unnecessary query disclosures while leaving time synchronization available to approved clients; the action is aimed at NTP control-query exposure; it leaves the central anonymous LDAP bind condition unresolved.
Question 375
A remediation meeting focuses on the following finding: A customer clicks Sign out from a shared terminal, yet an exported refresh token still obtains new access tokens from the identity endpoint afterward. Which proposed action best addresses its root cause?
- Mark authentication cookies Secure and require HTTPS throughout the site
- Verify issuer, audience, expiry, and signature for every consuming API
- Validate anti-CSRF tokens and request origin for state changes
- Invalidate server-side sessions and associated refresh tokens on logout
Explanation
Correct Answer
D:Backend revocation removes authorization from copies of the credential that exist outside the browser being logged out. That correction is linked to the fact that a logout operation that only clears client storage may leave a server-side session valid, permitting reuse of an earlier stolen bearer token.
Incorrect Answers
A:Transport restrictions and HTTPS redirect policy help prevent bearer tokens from leaking on non-TLS connections; the tested weakness is unrevoked logout token, not the secure cookie attribute configuration addressed here.
B:Recipient-specific validation stops a valid token minted for a different service from becoming a general-purpose cross-service credential; that safeguard does not directly close the unrevoked logout token route highlighted by the test.
C:Server-side request authenticity checks reject actions that merely carry automatically attached cookies without proof of authorized user intent; the proposed improvement would make sense for CSRF request forgery but not as the main fix here; the tested fault instead involves unrevoked logout token.
Question 376
The testing team seeks a specific preventive recommendation for this finding: Legacy programmable controllers become unstable when scanned, but operators still need an inventory of observed industrial protocols and device roles without active probes. What should be implemented?
- Use SPAN or TAP telemetry with coordinated asset-owner verification
- Enable supported DNP3 secure authentication and tightly manage control keys
- Disable unnecessary UPnP mapping or strictly constrain authorized clients
- Provision unique device certificates and lifecycle-aware revocation
Explanation
Correct Answer
A:Passive visibility maps many communicating devices while avoiding potentially disruptive scans against controllers with fragile protocol stacks. The technical basis for the recommendation is that passive OT discovery interprets mirrored network traffic and protocol messages without actively interrogating sensitive equipment, reducing assessment impact.
Incorrect Answers
B:Authenticated commands reduce spoofing of control operations, with segmentation still required for legacy devices and unsupported functions; the measure addresses a different trust boundary from the passive OT asset inventory finding.
C:Explicit port-forwarding policy prevents untrusted devices from silently publishing internal services through the edge gateway; the required correction concerns passive OT asset inventory, so this is not the targeted control.
D:Per-device credentials support accurate inventory, isolation, and renewal when only one endpoint is lost or retired; its security benefit applies principally to shared device identity, not the defect described; the tested fault instead involves passive OT asset inventory.
Question 377
Operations asks for a practical correction after the test found: Staff install business chat APKs delivered through unsolicited download links, bypassing the enterprise app marketplace and its mobile software approval workflow. What should the security team recommend?
- Restrict risky overlay and accessibility grants and monitor suspicious apps
- Enforce managed app sources and mobile threat defense
- Enforce HTTPS and prohibit cleartext network policies in app configuration
- Use device attestation and restrict access from unsupported rooted endpoints
Explanation
Correct Answer
B:Trusted distribution, signature checks, and endpoint policy reduce installation of repackaged applications from uncontrolled sites. That correction is linked to the fact that sideloading bypasses normal organizational app provenance workflows and can install modified packages if installation controls permit it.
Incorrect Answers
A:Platform safeguards and application controls reduce the ability of one app to draw deceptive credential forms over another; the action is aimed at mobile overlay credential theft; it leaves the central sideloaded APK risk condition unresolved.
C:TLS protects API exchanges in transit and platform policy stops accidental fallback to unencrypted endpoints; the tested weakness is sideloaded APK risk, not the cleartext mobile API traffic configuration addressed here.
D:Integrity checks and conditional access prevent high-trust applications from assuming ordinary platform protections remain intact on modified devices; that safeguard does not directly close the sideloaded APK risk route highlighted by the test.
Question 378
A control review considers a verified technical issue: A signed access token issued for a billing API is reused successfully against a different resource server because that server checks the signature but not the intended recipient. Which mitigation most directly addresses its cause?
- Verify issuer, audience, expiry, and signature for every consuming API
- Invalidate server-side sessions and associated refresh tokens on logout
- Keep session identifiers in secure cookies, not URLs
- Rotate the session token when authentication strength or privilege level changes
Explanation
Correct Answer
A:Recipient-specific validation stops a valid token minted for a different service from becoming a general-purpose cross-service credential. The underlying condition is that JWT audience claims identify the intended recipient; a valid signature alone does not authorize use of a token by every service trusting the issuer.
Incorrect Answers
B:Backend revocation removes authorization from copies of the credential that exist outside the browser being logged out; that change targets unrevoked logout token, while the confirmed weakness involves JWT audience validation.
C:Cookie-based storage with appropriate security attributes limits accidental token propagation through URLs and referring requests; it would improve session identifier in URL, not directly correct the reported JWT audience validation issue.
D:Regeneration limits fixation and stale-token reuse at the point where session authority increases; the measure addresses a different trust boundary from the JWT audience validation finding.
Question 379
A defender analyzing an approved exercise sees this pattern: During a sanctioned test, a database host unexpectedly performs a DNS lookup to an assessor-controlled domain after processing a malformed request. Which mechanism is most consistent with it?
- Error-based SQL injection
- Stacked query injection
- Time-based blind SQL injection
- Out-of-band SQL injection
Explanation
Correct Answer
D:Out-of-band SQL injection extracts evidence through a separate network channel, often DNS or HTTP, when direct response content cannot carry query results. This is why teams should restrict database outbound network paths and eliminate dynamic SQL concatenation; bound queries prevent injected operations; controlled egress reduces the chance that a database can contact arbitrary external receivers.
Incorrect Answers
A:Error-based SQL injection extracts information through database-generated errors when untrusted input alters SQL syntax and diagnostics reach the client; the observed evidence concerns out-of-band SQL injection instead.
B:Stacked SQL injection relies on executing additional statements in the same request, a capability controlled by database and connector behavior; the test record points specifically to out-of-band SQL injection, not this separate mechanism.
C:Time-based blind injection infers a condition through deliberate execution-time differences when application output conceals query results and errors; that behavior is distinct from the out-of-band SQL injection finding being classified.
Question 380
A production hardening ticket was raised after this confirmed observation: A mobile wallet opens a privileged screen from a custom URI issued by another app, trusting external deep-link arguments without a server-side authorization check. Which action best targets the risk?
- Review requested permissions and block unnecessary sensitive grants
- Deploy enterprise work profiles with controlled data-sharing rules
- Minimize exported components and enforce permissions for sensitive entry points
- Enforce HTTPS and prohibit cleartext network policies in app configuration
- Validate deep-link input and enforce authorization inside target activities
Explanation
Correct Answer
E:Server-side or in-app security checks stop external URLs from bypassing workflow restrictions through a trusted-looking app route. It targets the actual failure mode: deep links create cross-application entry points; intent-filter matching does not itself authorize the requested operation or validate untrusted parameters.
Incorrect Answers
A:Feature-based permission review limits unintended data collection and reduces blast radius when an app misbehaves; that safeguard does not directly close the deep-link validation route highlighted by the test.
B:Managed-profile restrictions limit casual copying of corporate records into personal apps while retaining separate personal device use; the proposed improvement would make sense for Android work profile isolation but not as the main fix here; the tested fault instead involves deep-link validation.
C:Explicit component exposure and caller checks prevent another application from invoking privileged behavior meant only for internal flows; the specific root cause belongs to deep-link validation, beyond this control's intended scope.
D:TLS protects API exchanges in transit and platform policy stops accidental fallback to unencrypted endpoints; that change targets cleartext mobile API traffic, while the confirmed weakness involves deep-link validation.