ECCouncil 312-50v13 (Certified Ethical Hacker v13) Practice Test 27

Question 260

The asset owner wants to stop the verified condition recurring: An API gateway waits for claimed large upload bodies sent at a trickle, exhausting worker slots despite the clients transmitting no substantial data. What is the most targeted improvement?

  1. Normalize cache keys and rate-limit expensive uncached operations
  2. Implement anti-spoofing filtering at source networks
  3. Use upstream filtering and volumetric DDoS mitigation
  4. Update NTP software and disable unnecessary monitoring commands
  5. Set request-body timeouts and minimum transfer rates
  6. Tune state limits and apply connection-rate controls before the firewall

Explanation

Correct Answer

E:

Body-read deadlines prevent many idle upload sessions from indefinitely consuming server processing capacity. The underlying condition is that slow POST attacks exhaust server resources during body receipt, distinct from attacks that hold connections open through incomplete headers.

Incorrect Answers

A:

Cache configuration and request controls reduce origin amplification from meaningless parameter variations while preserving valid user queries; that safeguard does not directly close the slow HTTP POST route highlighted by the test.

B:

Source-validation filters block forged victim addresses that make reflection possible, regardless of whether the protocol magnifies packet size; the proposed improvement would make sense for reflection without amplification but not as the main fix here; the tested fault instead involves slow HTTP POST.

C:

Provider-level controls drop unwanted volume before the limited access link becomes saturated, unlike an application-only request throttle; the specific root cause belongs to slow HTTP POST, beyond this control's intended scope.

D:

Patched and restricted control interfaces remove the oversized response path while preserving legitimate network time service; that change targets NTP amplification, while the confirmed weakness involves slow HTTP POST.

F:

Protection must preserve session-table capacity at the device handling flows; scaling application workers alone leaves this bottleneck intact; the measure addresses a different trust boundary from the slow HTTP POST finding.

Question 261

The post-assessment action plan cites this evidence: A suspicious sample has almost no readable strings or recognizable imports until it is executed in isolation and reveals a decrypted payload in memory. Which corrective measure should be prioritized?

  1. Combine static indicators with isolated dynamic observation
  2. Enable Secure Boot and verify boot integrity measurements
  3. Use integrity monitoring and execution controls on trusted binaries
  4. Investigate process ancestry and enforce endpoint response policy

Explanation

Correct Answer

A:

A controlled sandbox can expose unpacked behavior and runtime imports while avoiding conclusions based only on unusual file entropy. The underlying condition is that executable packers transform or encapsulate code and reveal it during execution; packing can serve legitimate distribution or malware evasion.

Incorrect Answers

B:

Signature-based boot validation and attestation make unauthorized boot-chain modifications more difficult to execute unnoticed; the required correction concerns packed executable analysis, so this is not the targeted control.

C:

File verification and controlled execution help identify infected hosts and interrupt propagation through modified application files; its security benefit applies principally to file-infecting virus, not the defect described; the tested fault instead involves packed executable analysis.

D:

Parent-child telemetry reveals unusual execution chains and supports containment of suspicious behavior across multiple different payload hashes; the exposure here is packed executable analysis, which calls for another protective mechanism.

Question 262

Consider this event from a scoped security assessment: A heavily throttled perimeter reports alternating open and filtered states for the same known service in successive scans. Which explanation fits the observed evidence?

  1. TCP NULL scan
  2. UDP service discovery
  3. Rate-limited scan results
  4. Firewall port-state ambiguity

Explanation

Correct Answer

C:

Scan rate and retransmission timing influence responses when devices enforce thresholds; an apparent missing port may be a rate-limit artifact. A targeted mitigation is to reduce authorized probe rates and correlate results with perimeter logs; controlled timing improves reproducibility and avoids mistaking defensive drops or transient congestion for a change in service configuration.

Incorrect Answers

A:

NULL scanning sends a zero-flag TCP segment and infers states from implementation-dependent responses; it is not a universally reliable port test; the scenario identifies rate-limited scan results, which has a different triggering condition.

B:

A UDP scan often cannot distinguish open from filtered ports when no response arrives; ICMP port-unreachable usually indicates the probed port is closed; the defining symptom in the prompt is associated with rate-limited scan results instead.

D:

Filtered results describe the scanner's network vantage point; ACLs, stateful inspection, and packet loss can hide a listener without stopping its local process; the reported conditions are characteristic of rate-limited scan results, not that path.

Question 263

The approved test uncovered this weakness: A web application lets an unauthenticated guest start a session that persists with the exact same bearer identifier after password login, allowing someone who knew the earlier identifier to reuse it. Which control would reduce the relevant exposure without relying on obscurity?

  1. Expire inactive sessions server-side and reauthenticate after the threshold
  2. Use HttpOnly cookies plus contextual output encoding
  3. Generate long unpredictable session identifiers using a cryptographic RNG
  4. Regenerate session identifiers after successful authentication

Explanation

Correct Answer

D:

Changing the session token at the privilege transition invalidates any previously planted identifier without requiring the victim to notice tampering. The safeguard responds to the underlying issue: session fixation works when a preauthentication identifier is accepted as an authenticated session, allowing the person who already knows that identifier to reuse it.

Incorrect Answers

A:

Server-enforced expiry prevents a copied or unattended token from remaining valid merely because client JavaScript failed to close the page; that change targets idle session timeout, while the confirmed weakness involves session fixation.

B:

HttpOnly blocks JavaScript cookie reads, while output encoding addresses the script execution source; neither control alone covers all session attacks; it would improve XSS-mediated cookie theft, not directly correct the reported session fixation issue.

C:

High-entropy tokens resist guessing; rate limiting is useful but cannot compensate for a trivially enumerable identifier space; the measure addresses a different trust boundary from the session fixation finding.

Question 264

The testing team seeks a specific preventive recommendation for this finding: A multiregion backend distributes the same database password inside container startup arguments, creating numerous plaintext copies despite access to a centralized credential vault. What should be implemented?

  1. Restrict metadata access and harden metadata token requirements
  2. Block public access and apply explicit identity-based bucket policies
  3. Store secrets in a managed vault and use workload identity retrieval
  4. Continuously assess configurations against preventive policy guardrails

Explanation

Correct Answer

C:

Centralized access policy and audit trails separate secret handling from source code, enabling rotation without distributing plaintext credentials in artifacts. The specific weakness being corrected is that application secret material embedded in code spreads across source control, build logs, and deployments, making controlled rotation and access auditing harder.

Incorrect Answers

A:

Workload network controls and hardened metadata APIs reduce credential retrieval from unintended server-side request paths; the exposure here is cloud secret management, which calls for another protective mechanism.

B:

Least-privilege resource policies and public-access guardrails stop anonymous reads while preserving approved application retrieval; the action is aimed at public object storage exposure; it leaves the central cloud secret management condition unresolved.

D:

Policy-as-code, change review, and recurring checks detect or block unsafe states after initial deployment; the tested weakness is cloud secret management, not the cloud posture drift configuration addressed here.

Question 265

An incident analyst is asked to classify this observed activity: Two compatible switches encrypt frames on a wired Ethernet link to prevent passive visibility along that physical segment. Which concept is the closest match?

  1. Promiscuous-mode capture
  2. MACsec link encryption
  3. LLMNR name-resolution poisoning
  4. MAC address table flooding

Explanation

Correct Answer

B:

MACsec protects Ethernet frames on a local link; it does not replace end-to-end application encryption across routers and other network hops. A targeted mitigation is to enable MACsec on supported links carrying sensitive internal traffic; layer-2 encryption reduces interception on the protected physical path while higher-layer TLS still protects data beyond those MACsec peers.

Incorrect Answers

A:

Promiscuous mode lets an interface pass additional received frames to capture software; a modern switched network still limits which frames physically reach that port; the reported conditions are characteristic of MACsec link encryption, not that path.

C:

Link-Local Multicast Name Resolution can resolve names on the local segment without ordinary DNS; spoofed responses can redirect clients to hostile listeners; this would classify another type of evidence, whereas the actual finding shows MACsec link encryption.

D:

CAM table flooding attempts to exhaust switch learning resources; some switches may flood unknown unicast frames more broadly when entries are unavailable; the relevant mechanism in the observed workflow is MACsec link encryption instead.

Question 266

The asset owner wants to stop the verified condition recurring: A branch switch still accepts the default read community used by several inventory tools; any device on the user VLAN can retrieve interface configuration data. What is the most targeted improvement?

  1. Apply directory ACLs and avoid anonymous broad searches
  2. Restrict rpcbind access to networks that need RPC services
  3. Patch time services and restrict diagnostic control queries
  4. Restrict share listing and access through SMB permissions and segmentation
  5. Use SNMPv3 with authentication, privacy, and management ACLs

Explanation

Correct Answer

E:

SNMPv3 protects management exchanges, while device and network restrictions reduce exposure of sensitive interface and configuration details. That correction is linked to the fact that SNMPv1/v2c community strings act as shared access tokens and do not provide encryption or strong authentication of management traffic.

Incorrect Answers

A:

Object and attribute permissions constrain information exposure more precisely than relying on a directory server's network obscurity; the required correction concerns SNMP default community, so this is not the targeted control.

B:

Management network controls suppress unnecessary program enumeration and narrow exposure of related RPC daemons; its security benefit applies principally to rpcbind service inventory, not the defect described; the tested fault instead involves SNMP default community.

C:

Current versions and access restrictions prevent unnecessary query disclosures while leaving time synchronization available to approved clients; the exposure here is SNMP default community, which calls for another protective mechanism.

D:

Share and NTFS permissions plus network isolation reduce unauthorized resource browsing even when SMB must remain available to staff; the action is aimed at SMB share enumeration; it leaves the central SNMP default community condition unresolved.

Question 267

An incident analyst is asked to classify this observed activity: A registration API automatically binds every JSON property to an account object, allowing a caller to set a privileged role field. Which concept is the closest match?

  1. Broken function-level authorization
  2. Operating-system command injection
  3. Insecure direct object reference
  4. Mass assignment

Explanation

Correct Answer

D:

Mass assignment happens when client-controlled properties are mapped into sensitive model attributes without an allowed-field boundary. For a production safeguard, operators can use explicit allowlists or data-transfer objects for writable fields; server-side property controls keep privileged attributes out of general user update workflows regardless of submitted JSON keys.

Incorrect Answers

A:

Function-level authorization failure lets a user reach privileged operations by calling endpoints without the required role or policy checks; this would classify another type of evidence, whereas the actual finding shows mass assignment.

B:

Command injection arises when untrusted text is interpreted as operating-system command syntax rather than a literal argument or data value; the relevant mechanism in the observed workflow is mass assignment instead.

C:

IDOR occurs when an application trusts a supplied object reference without verifying that the current identity may access that specific record; those effects are not the mass assignment pattern evidenced by the assessment.

Question 268

The approved test uncovered this weakness: A customer-support search box includes user-controlled text in a rendered response without contextual encoding; opening a crafted URL executes code in another person's browser. Which control would reduce the relevant exposure without relying on obscurity?

  1. Avoid shell invocation and pass validated arguments to direct process APIs
  2. Use atomic transactions or unique constraints for one-time operations
  3. Require unpredictable anti-CSRF tokens for state-changing requests
  4. Encode untrusted values for the exact HTML or script output context

Explanation

Correct Answer

D:

Context-appropriate escaping prevents user-controlled text from becoming executable markup while preserving legitimate displayed search terms. It targets the actual failure mode: reflected XSS returns unsafely embedded input in the immediate server response; the payload does not need to be permanently stored by the application.

Incorrect Answers

A:

Separating executable selection from user data prevents shell parsing from transforming input into additional commands; it would improve operating-system command injection, not directly correct the reported reflected cross-site scripting issue.

B:

Database-enforced consistency prevents two workers from independently passing a stale eligibility check and duplicating a benefit; the measure addresses a different trust boundary from the reflected cross-site scripting finding.

C:

Per-session tokens and origin checks bind sensitive operations to legitimate application flows beyond the presence of browser cookies; the required correction concerns reflected cross-site scripting, so this is not the targeted control.

Question 269

The assessor must classify two separate observations: A user profile value is stored harmlessly at registration but later concatenated into an administrator's reporting query and changes its behavior. In another test, a JSON document-store API accepts an object with a $ne operator in the place of an expected account-name string, letting a supplied predicate alter a login lookup. Select TWO technical concepts that correspond to these observations.

  1. NoSQL operator injection
  2. Second-order SQL injection
  3. Error-based SQL injection
  4. Stacked query injection
  5. Overprivileged application database account

Explanation

Correct Answers

A:

NoSQL injection abuses interpretation of structured query operators rather than SQL text syntax; unvalidated input types can alter database predicates; its indicators are tied to the NoSQL operator injection record, not to the finding involving second-order SQL injection.

B:

Second-order injection occurs when previously stored untrusted data becomes executable SQL syntax in a later, different processing step; this supports one of the required classifications, distinct from the evidence for NoSQL operator injection.

Incorrect Answers

C:

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 second-order SQL injection, NoSQL operator injection instead.

D:

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 second-order SQL injection, NoSQL operator injection, not this separate mechanism.

E:

Excess database privileges increase impact after SQL injection or credential theft, allowing unwanted modifications beyond the legitimate query purpose; that behavior is distinct from the second-order SQL injection, NoSQL operator injection finding being classified.

Question 270

A defender analyzing an approved exercise sees this pattern: A Linux host regularly launches a suspicious shell script under a service account after an unexpected new crontab entry appears. Which mechanism is most consistent with it?

  1. Scheduled-task persistence
  2. Cron-job persistence
  3. Registry Run-key persistence
  4. SSH authorized-key persistence

Explanation

Correct Answer

B:

Cron executes scheduled commands under a designated user context, so a malicious job can survive session termination and run unattended. For a production safeguard, operators can audit crontabs and apply least privilege to scheduler files; trusted task baselines and restricted edit permissions make unauthorized scheduled execution easier to detect and harder to establish.

Incorrect Answers

A:

Scheduled tasks can execute code on triggers or schedules without keeping the original user session alive, making them a possible persistence mechanism; the case demonstrates cron-job persistence rather than the alternate mechanism.

C:

Run keys cause configured programs to launch during user logon; they can maintain user-context execution across reboots without replacing a system service; the test record points specifically to cron-job persistence, not this separate mechanism.

D:

SSH public-key authentication trusts allowed public keys in account configuration; adding an unapproved key can preserve remote access independent of password rotation; that behavior is distinct from the cron-job persistence finding being classified.

Certified Ethical Hacker v13 (312-50v13) Practice Tests