VulnerabilityPublished 2 Oct 2025

CVE-2025-49090: Matrix specification · External Control of Critical State Data

Affects Matrix specificationSource CVE Database V5

Not known to be exploited · CVSS 7.1 High.

Data as of 26 Oct 2026, 17:16 UTC

CVSS 3.1 base score

7.1High

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

EPSS: 0.4% chance of exploitation in 30 days – higher than 40% of CVEsExploit Prediction Scoring System: the likelihood attackers will use this flaw soon.

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

Attack Vector: Network
Attack Complexity: High
Privileges Required: Low
User Interaction: None
Scope: Changed
Confidentiality: None
Integrity: High
Availability: Low

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

Attack Vector: Network: The vulnerable component is bound to the network stack and the set of possible attackers extends beyond the other options listed, 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: High: A successful attack depends on conditions beyond the attacker's control. That is, a successful attack cannot be accomplished at will, but requires the attacker to invest in some measurable amount of effort in preparation or execution against the vulnerable component before a successful attack can be expected. For example, a successful attack may require an attacker to: gather knowledge about the environment in which the vulnerable target/component exists; prepare the target environment to improve exploit reliability; or inject themselves into the logical network path between the target and the resource requested by the victim in order to read and/or modify network communications (e.g., a man in the middle attack).
Privileges Required: Low: The attacker is authorized with (i.e., requires) privileges that provide basic user capabilities that could normally affect only settings and files owned by a user. Alternatively, an attacker with Low privileges may have the ability to cause an impact only to non-sensitive resources.
User Interaction: None: The vulnerable system can be exploited without any interaction from any user.
Scope: Changed: An exploited vulnerability can affect resources beyond the security scope managed by the security authority of the vulnerable component. In this case, the vulnerable component and the impacted component are different and managed by different security authorities.
Confidentiality: None: There is no loss of confidentiality within the impacted component.
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: 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 2 Oct 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
Matrix Matrix specification	Affected =0	Fixed in–

AI-suggested

To mitigate CVE-2025-49090, European organizations should prioritize upgrading their Matrix implementations to version 1.16 or later, which includes the patched state resolution mechanism (room version 12 and State Resolution 2.1 or higher). Organizations should audit their current Matrix deployments to identify affected versions and room states. Network segmentation and strict access controls should be enforced to limit exposure of Matrix servers to untrusted networks. Monitoring and anomaly detection should be enhanced to identify unusual state changes or unauthorized state manipulations within Matrix rooms. Additionally, organizations should implement strict federation policies, limiting which external servers can participate in their Matrix rooms to reduce attack surface. For environments where immediate upgrading is not feasible, applying compensating controls such as enhanced logging, manual verification of critical state changes, and temporary restrictions on state-changing operations can reduce risk. Finally, organizations should stay informed about any emerging exploits or patches related to this vulnerability and apply updates promptly.

Description

The Matrix specification before 1.16 (i.e., with a room version before 12 and State Resolution before 2.1) has deficient state resolution.

Impact

For European organizations, the impact of CVE-2025-49090 can be substantial. Many European entities rely on Matrix-based communication platforms for secure, decentralized messaging and collaboration. Exploitation could allow attackers to alter the state of communication rooms, leading to misinformation, disruption of communication workflows, or unauthorized changes to permissions and membership states. This could undermine trust in communication channels, cause operational disruptions, and potentially lead to data integrity issues. Given the decentralized nature of Matrix, compromised state resolution could also propagate inconsistencies across federated servers, amplifying the impact. Critical sectors such as government agencies, financial institutions, healthcare providers, and large enterprises using Matrix for internal or external communications could face increased risks of espionage, sabotage, or data manipulation. The high attack complexity somewhat limits immediate exploitation, but the low privilege requirement and lack of user interaction mean that once an attacker overcomes complexity barriers, the attack could be stealthy and impactful.

CWE-642External Control of Critical State Data (opens in a new tab)
Class weaknessLikelihood of exploit: HighOWASP Top 10 A06:2025: Insecure Design (opens in a new tab)
The product stores security-critical state information about its users, or the product itself, in a location that is accessible to unauthorized actors.
Architecture and Design
Understand all the potential locations that are accessible to attackers. For example, some programmers assume that cookies and hidden form fields cannot be modified by an attacker, or they may not consider that environment variables can be modified before a privileged program is invoked.
Architecture and Design · Attack Surface Reduction
Store state information and sensitive data on the server side only.
Architecture and Design
Store state information on the server side only. Ensure that the system definitively and unambiguously keeps track of its own state and user state and has rules defined for legitimate state transitions.
OWASP Cheat Sheets
Secure Design Principles (opens in a new tab)
Attack patterns
Accessing/Intercepting/Modifying HTTP Cookies (opens in a new tab)
Exploitation of Trusted Identifiers (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

Affected software

Description

AI analysisMachine-generated, updated 2 Oct 2025, 18:42 UTC

WeaknessesCWE-642

Technical details

References

Community reviews

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