CVE-2025-6279VulnerabilityPublished 19 Jun 2025Updated 23 Jun 2025

CVE-2025-6279: Upsonic · Deserialization

Affects UpsonicSource CVE Database V5

Not known to be exploited · CVSS 5.1 Medium.

Data as of 25 Oct 2026, 19:02 UTC

CVSS 4.0 base score

5.1Medium

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

EPSS: 0.5% chance of exploitation in 30 days – higher than 43% of CVEsExploit Prediction Scoring System: the likelihood attackers will use this flaw soon.

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

Base metrics

Attack Vector: Adjacent
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

Threat metrics

Exploit Maturity: POC

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

Attack Vector: Adjacent: The vulnerable system is bound to a protocol stack, but the attack is limited at the protocol level to a logically adjacent topology. This can mean an attack must be launched from the same shared proximity (e.g., Bluetooth, NFC, or IEEE 802.11) or logical network (e.g., local IP subnet), or from within a secure or otherwise limited administrative domain (e.g., MPLS, secure VPN within an administrative network zone).
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.
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 19 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 2026-10-25.

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
GitHubupsonic/Upsonic`pkg:github/upsonic/Upsonic`Other threats	Affected =0.55.0 =0.55.1 =0.55.2 =0.55.3 =0.55.4 =0.55.5 =0.55.6	Fixed in–

Check your own hosts for these packages with threat-finder (opens in a new tab), our free open-source scanner.

AI-suggested

1. Upgrade Upsonic to version 0.55.7 or later where this vulnerability is patched. If an upgrade is not immediately possible, implement strict network segmentation to limit adjacent network access to systems running vulnerable Upsonic versions. 2. Employ application-layer filtering or input validation to detect and block malicious serialized data inputs targeting the cloudpickle.loads function. 3. Monitor network traffic and application logs for unusual deserialization activity or anomalies related to the /tools/add_tool endpoint. 4. Restrict privileges of users and services interacting with Upsonic to the minimum necessary to reduce the impact of potential exploitation. 5. Consider deploying runtime application self-protection (RASP) or endpoint detection and response (EDR) solutions capable of detecting deserialization attacks. 6. Conduct regular security assessments and penetration testing focusing on deserialization vulnerabilities in internal applications. 7. Educate development and operations teams about secure deserialization practices and the risks of using unsafe deserialization functions like cloudpickle.loads with untrusted input.

Description

A vulnerability, which was classified as critical, has been found in Upsonic up to 0.55.6. This issue affects the function cloudpickle.loads of the file /tools/add_tool of the component Pickle Handler. The manipulation leads to deserialization. The exploit has been disclosed to the public and may be used.

Impact

For European organizations using Upsonic versions up to 0.55.6, this vulnerability presents a moderate risk. Upsonic is typically used in environments requiring data serialization and deserialization, possibly in data processing or automation workflows. Exploitation could lead to unauthorized code execution, data manipulation, or service disruption, impacting confidentiality, integrity, and availability of critical systems. While the attack vector requires adjacent network access and low privileges, the lack of required user interaction lowers the barrier for exploitation in internal or segmented network environments. European organizations with sensitive data or critical infrastructure relying on Upsonic could face operational disruptions or data breaches if this vulnerability is exploited. The absence of known active exploits reduces immediate risk, but public disclosure increases the likelihood of future exploitation attempts. Given the medium severity and potential for lateral movement within networks, organizations should prioritize remediation to prevent escalation and protect sensitive assets.

References

Community reviews

Loading reviews…

Exploitation evidence

What to do

Affected software

Description

AI analysisMachine-generated, updated 23 Jun 2025, 19:40 UTC

Technical details

References

Community reviews

Related threats