CVE-2025-9019VulnerabilityPublished 15 Aug 2025

CVE-2025-9019: tcpreplay · Heap-based Buffer Overflow

Affects tcpreplaySource CVE Database V5

Not known to be exploited · CVSS 2.3 Low · fixed in 4.5.2 : update tcpreplay when convenient.

Data as of 26 Oct 2026, 06:26 UTC

CVSS 4.0 base score

2.3Low

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

EPSS: 1.0% chance of exploitation in 30 days – higher than 65% of CVEsExploit Prediction Scoring System: the likelihood attackers will use this flaw soon.
Patch: Available – fixed in 4.5.2

CVSS:4.0/AV:N/AC:H/AT:N/PR:N/UI:P/VC:N/VI:N/VA:L/SC:N/SI:N/SA:N/E:P

Base metrics

Attack Vector: Network
Attack Complexity: High
Attack Requirements: None
Privileges Required: None
User Interaction: Passive
Vulnerable system confidentiality: None
Vulnerable system integrity: None
Vulnerable system availability: Low
Subsequent system confidentiality: None
Subsequent system integrity: None
Subsequent system availability: None

Threat metrics

Exploit Maturity: POC

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

Attack Vector: Network: The vulnerable system is bound to the network stack and the set of possible attackers extends beyond the other options listed below, 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: The successful attack depends on the evasion or circumvention of security-enhancing techniques in place that would otherwise hinder the attack. These include: Evasion of exploit mitigation techniques, for example, circumvention of address space randomization (ASLR) or data execution prevention (DEP) must be performed for the attack to be successful; Obtaining target-specific secrets. The attacker must gather some target-specific secret before the attack can be successful. A secret is any piece of information that cannot be obtained through any amount of reconnaissance. To obtain the secret the attacker must perform additional attacks or break otherwise secure measures (e.g. knowledge of a secret key may be needed to break a crypto channel). This operation must be performed for each attacked target.
Attack Requirements: None: The successful attack does not depend on the deployment and execution conditions of the vulnerable system. The attacker can expect to be able to reach the vulnerability and execute the exploit under all or most instances of the vulnerability.
Privileges Required: None: The attacker is unauthorized prior to attack, and therefore does not require any access to settings or files of the vulnerable system to carry out an attack.
User Interaction: Passive: Successful exploitation of this vulnerability requires limited interaction by the targeted user with the vulnerable system and the attacker’s payload. These interactions would be considered involuntary and do not require that the user actively subvert protections built into the vulnerable system.
Vulnerable system confidentiality: None: There is no loss of confidentiality within the Vulnerable System.
Vulnerable system integrity: None: There is no loss of integrity within the Vulnerable System.
Vulnerable system availability: Low: Performance is reduced or there are interruptions in resource availability. Even if repeated exploitation of the vulnerability is possible, the attacker does not have the ability to completely deny service to legitimate users. The resources in the Vulnerable System are either partially available all of the time, or fully available only some of the time, but overall there is no direct, serious consequence to the Vulnerable System.
Subsequent system confidentiality: None: There is no loss of confidentiality within the Subsequent System or all confidentiality impact is constrained to the Vulnerable System.
Subsequent system integrity: None: There is no loss of integrity within the Subsequent System or all integrity impact is constrained to the Vulnerable System.
Subsequent system availability: None: There is no impact to availability within the Subsequent System or all availability impact is constrained to the Vulnerable System.
Exploit Maturity: POC: Based on threat intelligence sources each of the following must apply: · Proof-of-concept is publicly available · No knowledge of reported attempts to exploit this vulnerability · No knowledge of publicly available solutions used to simplify attempts to exploit the vulnerability

Definitions: FIRST CVSS v4.0 specification.

Exploitation evidence

Disclosed: evidence found.
CVE published 15 Aug 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

Affected software

Product	Affected	Fixed in
tcpreplay	Affected =4.5.1	Fixed in–

AI-suggested

The primary mitigation is to upgrade tcpreplay to version 4.5.2 or later, where the vulnerability has been fixed. Organizations should audit their environments to identify any instances of tcpreplay 4.5.1 or earlier and prioritize patching or upgrading those systems. If upgrading is not immediately possible, restricting network access to systems running tcpreplay, especially limiting exposure to untrusted networks, can reduce attack surface. Employing network segmentation and firewall rules to isolate testing environments is recommended. Additionally, monitoring logs and network traffic for unusual activity related to tcpreplay usage can help detect potential exploitation attempts. Security teams should also review and harden user interaction workflows involving tcpreplay to minimize the risk of exploitation. Finally, maintaining an up-to-date inventory of network testing tools and applying security patches promptly will help prevent similar vulnerabilities from being exploited.

Description

A vulnerability has been found in tcpreplay 4.5.1. This vulnerability affects the function mask_cidr6 of the file cidr.c of the component tcpprep. The manipulation leads to heap-based buffer overflow. The attack can be initiated remotely. The complexity of an attack is rather high. The exploitation appears to be difficult. The exploit has been disclosed to the public and may be used. The researcher is able to reproduce this with the latest official release 4.5.1 and the current master branch. The code maintainer cannot reproduce this for 4.5.2-beta1. In his reply the maintainer explains that "[i]n that case, this is a duplicate that was fixed in 4.5.2."

Impact

For European organizations, the impact of this vulnerability is generally low but context-dependent. Organizations using tcpreplay 4.5.1 for network testing, security research, or traffic replay could face risks of service disruption or potential exploitation leading to arbitrary code execution if attackers chain this vulnerability with others. Since tcpreplay is not typically deployed in production environments but rather in controlled testing or research settings, the risk to critical infrastructure or business operations is limited. However, organizations in sectors with high reliance on network security testing, such as telecommunications, cybersecurity firms, and research institutions, could be more affected. The remote attack vector and lack of required privileges mean that exposed systems running vulnerable versions could be targeted by remote attackers, especially if the tool is accessible over a network. The low CVSS score and absence of known exploits in the wild reduce immediate urgency but do not eliminate the need for remediation. European organizations should consider the potential for indirect impacts, such as disruption of security testing workflows or exploitation in multi-stage attacks.

References

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Exploitation evidence

What to do

Affected software

Description

AI analysisMachine-generated, updated 15 Aug 2025, 12:33 UTC

Technical details

References

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