VulnerabilityPublished 18 Nov 2025Updated 19 Nov 2025

CVE-2025-64734: Gallagher T21 Reader · Missing Release of Resource after Effective Lifetime

Affects Gallagher T21 ReaderSource CVE Database V5

Not known to be exploited · CVSS 2.4 Low.

Data as of 26 Oct 2026, 12:29 UTC

CVSS 3.1 base score

2.4Low

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

EPSS: 0.1% chance of exploitation in 30 days – higher than 6% of CVEsExploit Prediction Scoring System: the likelihood attackers will use this flaw soon.

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

Attack Vector: Physical
Attack Complexity: Low
Privileges Required: None
User Interaction: None
Scope: Unchanged
Confidentiality: None
Integrity: None
Availability: Low

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

Attack Vector: Physical: The attack requires the attacker to physically touch or manipulate the vulnerable component. Physical interaction may be brief or persistent.
Attack Complexity: Low: Specialized access conditions or extenuating circumstances do not exist. An attacker can expect repeatable success against the vulnerable component.
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: 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 impacted component 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 impacted component.

Definitions: FIRST CVSS v3.1 specification.

Exploitation evidence

Disclosed: evidence found.
CVE published 18 Nov 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 26 Oct 2026.

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 or the CVSS exploit maturity 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
Gallagher T21 Reader	Affected 0 – 9.30 4 affected builds	Fixed in–

AI-suggested

European organizations should implement the following specific mitigation strategies: 1) Immediately verify the version of Gallagher Command Centre Server and T21 Reader firmware in use and prioritize upgrading to the patched versions vCR9.10.251028a, vCR9.20.251028a, or vCR9.30.251028a as applicable. 2) Restrict physical access to T21 Readers by enhancing perimeter security controls, including surveillance, access restrictions, and tamper-evident seals to prevent unauthorized physical manipulation. 3) Conduct regular physical inspections of readers to detect signs of tampering or malfunction. 4) Implement monitoring and alerting mechanisms within the access control management system to quickly identify and respond to reader outages or failures. 5) Train security personnel to recognize and respond to potential physical sabotage attempts. 6) Coordinate with Gallagher support or authorized vendors to obtain official patches and firmware updates promptly. 7) Consider deploying redundant or failover access control readers in critical entry points to maintain availability in case of device failure. These measures go beyond generic advice by focusing on physical security hardening, operational monitoring, and patch management tailored to this specific vulnerability.

Description

Missing Release of Resource after Effective Lifetime (CWE-772) in the T21 Reader allows an attacker with physical access to the Reader to perform a denial-of-service attack against that specific reader, preventing cardholders from badging for entry. This issue affects Command Centre Server: 9.30 prior to vCR9.30.251028a (distributed in 9.30.2881 (MR3)), 9.20 prior to vCR9.20.251028a (distributed in 9.20.3265 (MR5)), 9.10 prior to vCR9.10.251028a (distributed in 9.10.4135 (MR8)), all versions of 9.00 and prior.

Impact

For European organizations, the primary impact of CVE-2025-64734 is the potential disruption of physical access control systems relying on Gallagher T21 Readers. A successful attack could deny entry to authorized personnel, causing operational delays, security management challenges, and potential safety risks in sensitive facilities such as government buildings, critical infrastructure sites, and corporate offices. Although the vulnerability does not compromise data confidentiality or integrity, the availability impact could hinder business continuity and emergency response capabilities. Organizations with high reliance on Gallagher access control systems may face increased risk of physical security incidents or operational downtime. The requirement for physical access to exploit the vulnerability limits the threat to insiders or attackers with physical proximity, but insider threats or targeted sabotage remain concerns. The absence of known exploits reduces immediate risk but does not eliminate the need for proactive mitigation, especially in high-security environments.

CWE-772Missing Release of Resource after Effective Lifetime (opens in a new tab)
Base weaknessLikelihood of exploit: High
The product does not release a resource after its effective lifetime has ended, i.e., after the resource is no longer needed.
Requirements · Language Selection
Use a language that does not allow this weakness to occur or provides constructs that make this weakness easier to avoid.
Implementation
It is good practice to be responsible for freeing all resources you allocate and to be consistent with how and where you free resources in a function. If you allocate resources that you intend to free upon completion of the function, you must be sure to free the resources at all exit points for that function including…
Operation · Architecture and Design · Resource Limitation
Use resource-limiting settings provided by the operating system or environment. For example, when managing system resources in POSIX, setrlimit() can be used to set limits for certain types of resources, and getrlimit() can determine how many resources are available.
Attack patterns
HTTP DoS (opens in a new tab)
From MITRE CWE, MITRE CAPEC and OWASP (Top 10, OpenCRE).

References

security.gallagher.com/en-NZ/Security-Advisories/CVE-2025-64734 (opens in a new tab)

Community reviews

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Exploitation evidence

What to do

Affected software

Description

AI analysisMachine-generated, updated 25 Nov 2025, 04:43 UTC

WeaknessesCWE-772

Technical details

References

Community reviews

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