VulnerabilityPublished 12 Mar 2026

CVE-2026-3967: Alfresco Activiti · Deserialization

Affects Alfresco ActivitiSource CVE Database V5

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Public exploit available · CVSS 5.3 Medium.

Data as of 30 Oct 2026, 11:52 UTC

CVSS 4.0 base score

5.3Medium

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

EPSS: 0.2% chance of exploitation in 30 days – higher than 16% of CVEsExploit Prediction Scoring System: the likelihood attackers will use this flaw soon.

CVSS:4.0/AV:N/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: Network
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: 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: 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 12 Mar 2026
Detectable: no evidence on record.
No public nuclei template indexed
Weaponized: evidence found.
CVSS exploit maturity: proof of concept public
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), CVSS vector, the Metasploit, Exploit-DB and nuclei-templates index as of 30 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.
Weaponized: A Metasploit exploit module or Exploit-DB entry exists (Metasploit scanner modules do not count), 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
AlfrescoActiviti	Affected 7.0 – 8.8.0 29 affected builds	Fixed in–
Mavenorg.activiti/activiti`pkg:maven/org.activiti/activiti`Other threats	Affected 7.0 – 8.8.0 29 affected builds	Fixed in–

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AI-suggested

Until an official patch is released, organizations should implement multiple layers of defense to mitigate CVE-2026-3967. First, restrict network access to Alfresco Activiti instances by enforcing strict firewall rules and network segmentation to limit exposure to trusted users and systems only. Second, implement input validation and filtering at the application or proxy level to detect and block suspicious serialized data payloads targeting the vulnerable deserialization function. Third, monitor logs and network traffic for anomalous activity indicative of exploitation attempts, such as unusual serialized object streams or unexpected process variable changes. Fourth, consider deploying runtime application self-protection (RASP) or endpoint detection and response (EDR) solutions capable of detecting deserialization attacks. Fifth, isolate Activiti environments from critical infrastructure and sensitive data stores to contain potential breaches. Finally, maintain an incident response plan specifically addressing deserialization vulnerabilities and prepare to apply patches promptly once available. Organizations should also engage with Alfresco support channels to track patch releases and advisories.

Description

CVE-2026-3967 is a medium severity deserialization vulnerability in Alfresco Activiti versions up to 7.19 and 8.8.0. The flaw exists in the deserialize/createObjectInputStream function within the Process Variable Serialization System, allowing remote attackers to exploit unsafe deserialization. No authentication or user interaction is required, and the vulnerability can be triggered remotely over the network. Although an exploit has been published, there are no known active exploits in the wild yet. The vendor has not responded to disclosure attempts, and no official patches are currently available. This vulnerability could lead to partial compromise of confidentiality, integrity, and availability of affected systems. Organizations using Alfresco Activiti should apply strict input validation, isolate vulnerable components, and monitor for suspicious activity until a patch is released.

Impact

The exploitation of CVE-2026-3967 can lead to unauthorized remote code execution or manipulation of process variables within Alfresco Activiti, potentially compromising the confidentiality, integrity, and availability of business process data. Organizations relying on Activiti for workflow automation and process management may face disruption of critical operations, data leakage, or unauthorized control over process execution. Given the vulnerability requires no authentication and can be triggered remotely, attackers can target exposed Activiti instances over the internet or internal networks. This could facilitate lateral movement within enterprise environments or serve as an entry point for broader attacks. The lack of vendor response and patches increases the window of exposure, raising the risk of exploitation especially in environments where Activiti is internet-facing or insufficiently segmented. While no active exploits in the wild are currently reported, the availability of a public exploit increases the likelihood of future attacks. The impact is particularly severe for organizations with sensitive workflows, regulated data, or high availability requirements.

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Exploitation evidence

What to do

Affected software

Description

AI analysisMachine-generated, updated 19 Mar 2026, 02:33 UTC

Technical details

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