VulnerabilityPublished 25 Jun 2025

CVE-2025-6603: coldfunction qCUDA · Integer Overflow

Affects coldfunction qCUDASource CVE Database V5

Not known to be exploited · CVSS 4.8 Medium.

Data as of 26 Oct 2026, 09:16 UTC

CVSS 4.0 base score

4.8Medium

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

EPSS: 0.1% chance of exploitation in 30 days – higher than 5% of CVEsExploit Prediction Scoring System: the likelihood attackers will use this flaw soon.

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

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

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

Attack Vector: Local: The vulnerable system is not bound to the network stack and the attacker’s path is via read/write/execute capabilities. Either the attacker exploits the vulnerability by accessing the target system locally (e.g., keyboard, console), or through terminal emulation (e.g., SSH); or the attacker relies on User Interaction by another person to perform actions required to exploit the vulnerability (e.g., using social engineering techniques to trick a legitimate user into opening a malicious document).
Attack Complexity: Low: The attacker must take no measurable action to exploit the vulnerability. The attack requires no target-specific circumvention to exploit the vulnerability. An attacker can expect repeatable success against the vulnerable system.
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: Low: The attacker requires privileges that provide basic capabilities that are typically limited to settings and resources owned by a single low-privileged user. Alternatively, an attacker with Low privileges has the ability to access only non-sensitive resources.
User Interaction: None: The vulnerable system can be exploited without interaction from any human user, other than the attacker.
Vulnerable system confidentiality: Low: There is some loss of confidentiality. Access to some restricted information is obtained, but the attacker does not have control over what information is obtained, or the amount or kind of loss is limited. The information disclosure does not cause a direct, serious loss to the Vulnerable System.
Vulnerable system integrity: Low: Modification of data is possible, but the attacker does not have control over the consequence of a modification, or the amount of modification is limited. The data modification does not have a direct, serious impact to 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.

Definitions: FIRST CVSS v4.0 specification.

Exploitation evidence

Disclosed: evidence found.
CVE published 25 Jun 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 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. Restrict local access strictly: Implement robust access controls and monitoring to ensure only authorized personnel can access systems running qCUDA. 2. Employ least privilege principles: Limit user privileges on affected systems to reduce the risk of exploitation by low-privilege users. 3. Monitor for anomalous behavior: Use host-based intrusion detection systems (HIDS) to detect unusual memory or process behavior indicative of exploitation attempts. 4. Coordinate with vendor: Engage with coldfunction to obtain timely updates or patches, given the rolling release model complicates version tracking. 5. Implement application whitelisting and integrity checks: Prevent unauthorized modifications to qCUDA binaries or related components. 6. Isolate critical GPU-accelerated workloads: Use network segmentation and virtualization isolation to limit the blast radius of any potential exploit. 7. Prepare incident response plans: Ensure readiness to respond to potential exploitation, including forensic capabilities to analyze local attacks. 8. Regularly audit and update system configurations: Maintain up-to-date system hardening to reduce attack surface and prevent privilege escalation paths.

Description

A vulnerability was found in coldfunction qCUDA up to db0085400c2f2011eed46fbc04fdc0873141688e. It has been rated as problematic. Affected by this issue is the function qcow_make_empty of the file qCUDA/qcu-device/block/qcow.c. The manipulation of the argument s->l1_size leads to integer overflow. The attack needs to be approached locally. This product is using a rolling release to provide continious delivery. Therefore, no version details for affected nor updated releases are available.

Impact

For European organizations, the impact of CVE-2025-6603 depends largely on the deployment of coldfunction qCUDA within their infrastructure. Given that qCUDA is a specialized product likely related to GPU virtualization or acceleration, organizations in sectors such as high-performance computing, research institutions, and industries relying on GPU-accelerated workloads may be affected. The integer overflow could allow local attackers to escalate privileges or cause denial of service through memory corruption, potentially disrupting critical computational tasks or exposing sensitive data processed on affected systems. The requirement for local access limits remote exploitation, but insider threats or compromised accounts could leverage this vulnerability. The rolling release model and lack of clear patching information increase the risk window. European organizations with strict data protection regulations (e.g., GDPR) must consider the confidentiality risks, especially if qCUDA is used in environments processing personal or sensitive data. Operational continuity could also be impacted if the vulnerability is exploited to cause system crashes or instability.

References

Community reviews

Loading reviews…