CVE-2023-2593VulnerabilityPublished 30 Jul 2025Updated 20 Nov 2025

CVE-2023-2593: Infinite Loop

Source CVE Database V5

Not known to be exploited · CVSS 5.9 Medium.

Data as of 26 Oct 2026, 06:26 UTC

CVSS 3.1 base score

5.9Medium

How severe the flaw is on the 0–10 CVSS scale.

EPSS: 0.7% chance of exploitation in 30 days – higher than 55% of CVEsExploit Prediction Scoring System: the likelihood attackers will use this flaw soon.

CVSS:3.1/AV:N/AC:H/PR:N/UI:N/S:U/C:N/I:N/A:H

Attack Vector: Network
Attack Complexity: High
Privileges Required: None
User Interaction: None
Scope: Unchanged
Confidentiality: None
Integrity: None
Availability: High

Bold values are the worst case: easiest to exploit or largest impact.

Attack Vector: Network: The vulnerable component is bound to the network stack and the set of possible attackers extends beyond the other options listed, up to and including the entire Internet. Such a vulnerability is often termed 'remotely exploitable' and can be thought of as an attack being exploitable at the protocol level one or more network hops away (e.g., across one or more routers).
Attack Complexity: High: A successful attack depends on conditions beyond the attacker's control. That is, a successful attack cannot be accomplished at will, but requires the attacker to invest in some measurable amount of effort in preparation or execution against the vulnerable component before a successful attack can be expected. For example, a successful attack may require an attacker to: gather knowledge about the environment in which the vulnerable target/component exists; prepare the target environment to improve exploit reliability; or inject themselves into the logical network path between the target and the resource requested by the victim in order to read and/or modify network communications (e.g., a man in the middle attack).
Privileges Required: None: The attacker is unauthorized prior to attack, and therefore does not require any access to settings or files to carry out an attack.
User Interaction: None: The vulnerable system can be exploited without any interaction from any user.
Scope: Unchanged: An exploited vulnerability can only affect resources managed by the same security authority. In this case, the vulnerable component and the impacted component are either the same, or both are managed by the same security authority.
Confidentiality: None: There is no loss of confidentiality within the impacted component.
Integrity: None: There is no loss of integrity within the impacted component.
Availability: High: There is total loss of availability, resulting in the attacker being able to fully deny access to resources in the impacted component; this loss is either sustained (while the attacker continues to deliver the attack) or persistent (the condition persists even after the attack has completed). Alternatively, the attacker has the ability to deny some availability, but the loss of availability presents a direct, serious consequence to the impacted component (e.g., the attacker cannot disrupt existing connections, but can prevent new connections; the attacker can repeatedly exploit a vulnerability that, in each instance of a successful attack, leaks a only small amount of memory, but after repeated exploitation causes a service to become completely unavailable).

Definitions: FIRST CVSS v3.1 specification.

Exploitation evidence

Disclosed: evidence found.
CVE published 30 Jul 2025
Detectable: no evidence on record.
No public nuclei template indexed
Weaponised: no evidence on record.
No public exploit code indexed in Metasploit or Exploit-DB
Exploited in the wildExploited: no evidence on record.
Not in CISA KEV and no source reports exploitation
Observed by OffSeq MirageSeen by Mirage: no evidence on record.
No attack traffic recorded by OffSeq Mirage sensors

A missing step is not evidence of safety. Sources: cve.org (opens in a new tab), the Metasploit, Exploit-DB and nuclei-templates index as of 2026-10-26.

Disclosed: The CVE record is public on cve.org. Its publication is t = 0.
Detectable: A public nuclei template can find exposed instances, for defenders and attackers alike.
Weaponised: Public exploit code exists in Metasploit or Exploit-DB, or CISA SSVC reports a public proof of concept.
Exploited in the wild: CISA KEV lists it, CISA SSVC rates exploitation active, or a source reports attacks.
Observed by OffSeq Mirage: OffSeq Mirage honeypot sensors recorded attack traffic for this CVE, or found exposed hosts without attack traffic.

Moments are spaced evenly, not to scale; a dashed line marks a gap of six months or more. Deltas count from t = 0. Sources that give only a date (CISA KEV, Exploit-DB, or a time of exactly 00:00Z) read “same day” rather than hours. Metasploit modules carry the flaw’s disclosure date, not their release date, and nuclei templates carry no date, so both appear above but not on the timeline.

What to do

AI-suggested

1. Monitor vendor advisories and apply official Linux kernel patches promptly once released to address CVE-2023-2593. 2. Implement network-level rate limiting and connection throttling to reduce the risk of resource exhaustion from excessive TCP connection attempts. 3. Deploy intrusion detection and prevention systems (IDS/IPS) with signatures or heuristics to detect anomalous TCP connection patterns indicative of exploitation attempts. 4. Harden network perimeter defenses by restricting unnecessary inbound TCP traffic and employing firewall rules to limit exposure of vulnerable services. 5. Use kernel hardening features and resource limits (e.g., cgroups) to contain the impact of potential infinite loops and memory leaks. 6. Conduct regular system and network monitoring to identify unusual CPU or memory usage spikes that may indicate exploitation attempts. 7. Prepare incident response plans that include steps for mitigating DoS conditions caused by kernel resource exhaustion. 8. Consider deploying redundant systems and failover mechanisms to maintain service availability during attack scenarios. 9. Engage with Linux distribution maintainers and security communities to stay informed about patch availability and best practices.

Description

CVE-2023-2593 is a medium-severity vulnerability in the Linux kernel related to TCP connection handling. It involves an infinite loop caused by a loop with an unreachable exit condition, leading to memory not being released after its effective lifetime. An unauthenticated attacker can exploit this flaw remotely to cause a denial of service (DoS) by exhausting system resources. The vulnerability does not impact confidentiality or integrity but severely affects availability. Exploitation requires network access but no authentication or user interaction. No known exploits are currently reported in the wild. The vulnerability affects Linux kernel versions prior to the patch and is relevant to systems heavily reliant on Linux servers. European organizations using Linux-based infrastructure, especially in countries with high Linux adoption in critical sectors, are at risk. Mitigation involves applying kernel patches once available, monitoring network traffic for abnormal connection patterns, and implementing rate limiting on TCP connections. Countries like Germany, France, the Netherlands, and the UK are likely most affected due to their extensive use of Linux in enterprise and government environments.

Impact

For European organizations, the primary impact of CVE-2023-2593 is the risk of denial of service attacks against Linux-based servers and network infrastructure. This can lead to service outages, degraded performance, and potential disruption of critical business operations, especially in sectors like finance, telecommunications, government, and cloud service providers that heavily rely on Linux systems. The unavailability of services can affect customer trust, regulatory compliance (such as GDPR mandates on service continuity), and operational efficiency. Since the vulnerability requires no authentication and can be exploited remotely, it increases the attack surface for threat actors aiming to disrupt services. The medium severity score reflects that while confidentiality and integrity are not compromised, the availability impact can be significant, particularly for high-traffic servers. Organizations with large-scale Linux deployments or those exposed to public networks are at higher risk. The lack of known exploits in the wild currently reduces immediate threat but does not eliminate future exploitation possibilities. The infinite loop can also complicate incident response and recovery due to resource exhaustion.

Summary

CVE-2023-2593 is a vulnerability identified in the Linux kernel's TCP connection handling subsystem. The flaw arises from a loop construct with an unreachable exit condition, effectively creating an infinite loop scenario during the processing of new TCP connections. This infinite loop prevents the release of allocated memory after its intended lifetime, causing resource exhaustion. The vulnerability can be triggered remotely by an unauthenticated attacker who sends crafted TCP connection requests, leading to a denial of service (DoS) condition by depleting kernel memory and CPU resources. The CVSS v3.1 score of 5.9 reflects a medium severity, with the vector indicating network attack vector (AV:N), high attack complexity (AC:H), no privileges required (PR:N), no user interaction (UI:N), unchanged scope (S:U), no impact on confidentiality or integrity (C:N/I:N), and high impact on availability (A:H). The vulnerability affects Linux kernel versions prior to the patch and is particularly concerning for servers and network devices running Linux that handle large volumes of TCP connections. Although no known exploits are reported in the wild, the potential for DoS attacks makes it a significant concern for operational continuity. The infinite loop and memory leak combination can degrade system performance and cause crashes, impacting service availability.

References

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