VulnerabilityPublished 2 Dec 2025Updated 26 Aug 2026

CVE-2025-59694: Improper Access Control for Volatile Memory Containing Boot Code

Source CVE Database V5

Not known to be exploited · CVSS 6.8 Medium · fixed in 13.6.12 : update affected systems when convenient.

Data as of 26 Oct 2026, 12:55 UTC

CVSS 3.1 base score

6.8Medium

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

EPSS: 0.3% chance of exploitation in 30 days – higher than 24% of CVEsExploit Prediction Scoring System: the likelihood attackers will use this flaw soon.
Patch: Available – fixed in 13.6.12

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

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

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: High: There is total loss of confidentiality, resulting in all resources within the impacted component being divulged to the attacker. Alternatively, access to only some restricted information is obtained, but the disclosed information presents a direct, serious impact.
Integrity: High: There is a total loss of integrity, or a complete loss of protection. For example, the attacker is able to modify any/all files protected by the impacted component. Alternatively, only some files can be modified, but malicious modification would present a direct, serious consequence to 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 2 Dec 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

AI-suggested

European organizations should immediately review and strengthen physical security controls around Entrust nShield HSM appliances to prevent unauthorized physical access, including secure data center access policies, surveillance, and tamper-evident seals. Implement strict access controls and monitoring for personnel with physical access to HSM hardware. Employ hardware inventory and firmware integrity verification tools to detect unauthorized firmware modifications. Coordinate with Entrust to obtain and apply any forthcoming firmware patches or updates addressing this vulnerability. Consider deploying hardware security modules with secure boot and firmware validation features that resist unauthorized firmware changes. Establish incident response plans that include procedures for detecting and responding to firmware tampering. Regularly audit and log all firmware upgrade activities and restrict firmware upgrade capabilities to trusted administrators. For critical systems, consider redundant HSM deployments and key backup strategies to maintain cryptographic operations if a device is compromised. Finally, educate staff about the risks of physical attacks and insider threats related to hardware security modules.

Description

The Chassis Management Board in Entrust nShield Connect XC, nShield 5c, and nShield HSMi through 13.6.11, or 13.7 (patched in 13.6.12 (LTS) and 13.9.0 (STS)), allows a physically proximate attacker to persistently modify firmware and influence the (insecurely configured) appliance boot process. To exploit this, the attacker must modify the firmware via JTAG or perform an upgrade to the chassis management board firmware. This is called F03.

Impact

For European organizations, the impact of CVE-2025-59694 is significant due to the critical role Entrust nShield HSMs play in securing cryptographic keys, digital signatures, and other sensitive operations. Successful exploitation could lead to unauthorized firmware control, allowing attackers to bypass cryptographic protections, extract keys, or manipulate cryptographic operations, thereby compromising data confidentiality and integrity. This could affect sectors such as finance, government, telecommunications, and critical infrastructure where Entrust HSMs are deployed. The requirement for physical access limits remote exploitation but raises concerns about insider threats, supply chain attacks, or attacks on data centers with inadequate physical security. The persistent nature of the firmware modification means that even after reboot or software updates, the compromised state could remain, complicating detection and remediation. The lack of available patches increases the urgency for organizations to implement compensating controls. Overall, this vulnerability threatens the foundational trust in cryptographic security for affected European entities, potentially leading to data breaches, regulatory non-compliance, and operational disruptions.

CWE-1274Improper Access Control for Volatile Memory Containing Boot Code (opens in a new tab)
Base weakness
The product conducts a secure-boot process that transfers bootloader code from Non-Volatile Memory (NVM) into Volatile Memory (VM), but it does not have sufficient access control or other protections for the Volatile Memory.
Architecture and Design
Ensure that the design of volatile-memory protections is enough to prevent modification from an adversary or untrusted code.
Testing
Test the volatile-memory protections to ensure they are safe from modification or untrusted code.
OWASP Cheat Sheets
Docker Security (opens in a new tab)
Third Party Javascript Management (opens in a new tab)
Virtual Patching (opens in a new tab)
OWASP ASVS 4.0.3
V1.4.4 (opens in a new tab)
V1.4.5 (opens in a new tab)
V1.10.1 (opens in a new tab)
Attack patterns
Infected Memory (opens in a new tab)
Exploitation of Improperly Configured or Implemented Memory Protections (opens in a new tab)
From MITRE CWE, MITRE CAPEC and OWASP (Top 10, OpenCRE).

References

Community reviews

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Exploitation evidence

What to do

Description

AI analysisMachine-generated, updated 9 Dec 2025, 16:46 UTC

WeaknessesCWE-1274

Technical details

References

Community reviews

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