Cyber Resilience

CVE-2023-51316

DoS in Phpjabbers Bus Reservation System 1.1

Public PoCDoS
Published
20 February 2025
Modified
04 November 2025
Patch / advisory
CVSS Score v3.1 7.5
Click a component to see what it means
Raw vectorCVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:H
EPSS Score 0.0072 51th percentile
Risk Priority 59 floored blend · peak EPSS

Summary

CVE-2023-51316 is a high-severity Uncontrolled Resource Consumption (CWE-400) vulnerability in Phpjabbers Bus Reservation System. Its CVSS base score is 7.5 (High).

Operationally, exploitation aligns with the MITRE ATT&CK technique OS Exhaustion Flood (T1499.001); ranked in the top 49% of CVEs by exploit likelihood; it is not currently listed in the CISA KEV catalog; a public proof-of-concept is referenced.

The strongest mitigations our analysis identified map to SC-5 (Denial-of-service Protection) and SC-6 (Resource Availability) — see the control section below for these in your framework.

Deeper analysis AI-assisted summary

Synthesised by an AI model from the NVD description and linked references — a reading aid, not an authoritative source.

CVE-2023-51316 is a vulnerability stemming from a lack of rate limiting in the 'Forgot Password' feature of PHPJabbers Bus Reservation System version 1.1. This flaw enables attackers to trigger an excessive volume of email generation targeted at a legitimate user account, resulting in a denial-of-service (DoS) condition. The issue is classified under CWE-400 (Uncontrolled Resource Consumption) and carries a CVSS v3.1 base score of 7.5 (AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:H), indicating high severity primarily due to its impact on availability.

Unauthenticated attackers (PR:N) can exploit this vulnerability remotely over the network (AV:N) with low complexity and no user interaction required. By repeatedly submitting forgot password requests for a valid user, an attacker can overwhelm the system's email generation process, flooding the mail server or service with a large number of messages and causing resource exhaustion that disrupts service availability for the targeted user or the application as a whole.

Advisories detailing the vulnerability are available from Packet Storm Security, including exploit details at http://packetstormsecurity.com/files/176497/PHPJabbers-Bus-Reservation-System-1.1-Missing-Rate-Limiting.html and https://packetstorm.news/files/id/176497. The official product page at https://www.phpjabbers.com/bus-reservation-system/#sectionDemo provides demo access but no specific patch or mitigation guidance is referenced in the available disclosures. Security practitioners should implement rate limiting on forgot password endpoints and monitor email generation logs in affected deployments.

EU & UK References

Vulnerability Data

A lack of rate limiting in the 'Forgot Password' feature of PHPJabbers Bus Reservation System v1.1 allows attackers to send an excessive amount of email for a legitimate user, leading to a possible Denial of Service (DoS) via a large…

more

amount of generated e-mail messages.

CWE(s)

Related Threats

MITRE ATT&CK Enterprise Techniques

T1499.001 OS Exhaustion Flood Impact
Adversaries may launch a denial of service (DoS) attack targeting an endpoint's operating system (OS).
T1498 Network Denial of Service Impact
Adversaries may perform Network Denial of Service (DoS) attacks to degrade or block the availability of targeted resources to users.
T1499 Endpoint Denial of Service Impact
Adversaries may perform Endpoint Denial of Service (DoS) attacks to degrade or block the availability of services to users.
T1499.002 Service Exhaustion Flood Impact
Adversaries may target the different network services provided by systems to conduct a denial of service (DoS).
T1499.003 Application Exhaustion Flood Impact
Adversaries may target resource intensive features of applications to cause a denial of service (DoS), denying availability to those applications.
Derived from this CVE’s CWE(s) via the direct CWE→ATT&CK cross-walk.

CVEs Like This One

CVE-2023-53877Same product: Phpjabbers Bus Reservation System
CVE-2023-51314Same vendor: Phpjabbers
CVE-2023-4111Same product: Phpjabbers Bus Reservation System
CVE-2023-48840Same vendor: Phpjabbers
CVE-2023-51319Same product: Phpjabbers Bus Reservation System
CVE-2023-48833Same vendor: Phpjabbers
CVE-2023-51301Same vendor: Phpjabbers
CVE-2023-48834Same vendor: Phpjabbers
CVE-2023-51293Same vendor: Phpjabbers
CVE-2023-51318Same product: Phpjabbers Bus Reservation System

Affected Assets

phpjabbers
bus reservation system
1.1

Mitigating Controls

Mitigating Controls (NIST 800-53 r5) AI

SC-5 directly limits the effects of resource-exhaustion events that constitute uncontrolled consumption.

SC-6 enforces explicit allocation limits on resources, structurally preventing the weakness from occurring.

Process isolation confines resource consumption to separate domains, reducing blast radius without stopping the root flaw.

Mitigating Controls (NIST CSF 2.0) AI

Derived directly from the weakness types (CWEs) cited in the NVD entry via our AI-authored CWE→CSF cross-walk (authority under review) — links open the control.

PR.IR-04 mostly match
prevents

Explicitly requires monitoring and maintaining resource capacity, directly addressing uncontrolled consumption to preserve availability.

DE.CM-09 partial match
prevents

Continuous monitoring of computing resources can detect resource exhaustion but does not itself enforce allocation limits.

PR.IR-03 partial match
prevents

Resilience mechanisms such as avoiding single points of failure indirectly reduce impact of resource exhaustion.

PR.PS-01 partial match
prevents

Hardened configuration baselines can include resource quotas and limits that constrain consumption.

Mitigating Controls (ISO/IEC 27001:2022 Annex A) AI

Derived directly from the weakness types (CWEs) cited in the NVD entry via our AI-authored CWE→ISO cross-walk (authority under review) — links open the control.

finds

Resource-utilization monitoring and alerting on bottlenecks or overloads limits the impact of denial-of-service or resource-exhaustion attacks.

prevents

By continuously monitoring utilization, stress-testing peak loads, and maintaining documented plans to scale or throttle resources, the control directly limits an attacker’s ability to drive a system into uncontrolled resource exhaustion.

finds

Pre-agreed severity-based prioritization and resource allocation during incident triage reduce the likelihood that an attacker-induced resource exhaustion will overwhelm the organization before corrective action is taken.

mitigates

Business-continuity plans that include resource-management controls reduce the likelihood that an attacker can trigger uncontrolled resource consumption by forcing the system into a degraded or fallback state.

mitigates

Defining RTOs and capacity requirements for ICT services during business-impact analysis forces organizations to provision sufficient resources and throttling mechanisms, reducing the likelihood that an attacker can induce denial-of-service through uncontrolled resource consumption.

finds

Early notification of anomalous resource consumption or system malfunctions enables throttling or isolation before availability is lost.

References