CVE-2026-23989VulnerabilityPublished 6 Feb 2026

CVE-2026-23989: opencloud-eu reva · Incorrect Authorization

Affects opencloud-eu revaSource CVE Database V5

Not known to be exploited · CVSS 8.2 High : upgrade to 2.42.3 or 2.40.3 soon.

Data as of 26 Oct 2026, 06:26 UTC

CVSS 3.1 base score

8.2High

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

EPSS: 0.3% chance of exploitation in 30 days – higher than 22% of CVEsExploit Prediction Scoring System: the likelihood attackers will use this flaw soon.
Patch: Available – fixed in 2.42.3, 2.40.3

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

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

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: 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: 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 on the impacted component.
Availability: None: There is no impact to availability within the impacted component.

Definitions: FIRST CVSS v3.1 specification.

Exploitation evidence

Disclosed: evidence found.
CVE published 6 Feb 2026
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 2026-10-26.

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

Upgrade reva to 2.42.3 or 2.40.3; opencloud-eu/reva to 2.40.3.

Affected software

Product	Affected	Fixed in
opencloud-eureva	Affected <2.40.3 >=2.41.0 <2.42.3	Fixed in 2.42.3 2.40.3
GitHubopencloud-eu/reva`pkg:github/opencloud-eu/reva`Other threats	Affected <2.40.3	Fixed in 2.40.3

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

AI-suggested

European organizations should immediately verify their Reva versions and upgrade to 2.40.3 or 2.42.3 or later to remediate the vulnerability. In environments where immediate patching is not feasible, organizations should restrict network access to the archiver service and GRPC endpoints to trusted internal networks only, using firewall rules or network segmentation. Implement strict monitoring and logging of public link creation and archiving activities to detect anomalous behavior indicative of exploitation attempts. Review and minimize the use of public links, applying the principle of least privilege to resource sharing. Employ additional access controls such as multi-factor authentication and IP whitelisting where possible to reduce unauthorized access risks. Conduct regular security audits and vulnerability scans focusing on OpenCloud components. Finally, educate users about the risks of public link sharing and enforce policies to limit exposure.

Description

REVA is an interoperability platform. Prior to 2.42.3 and 2.40.3, a bug in the GRPC authorization middleware of the "Reva" component of OpenCloud allows a malicious user to bypass the scope verification of a public link. By exploiting this via the the "archiver" service this can be leveraged to create an archive (zip or tar-file) containing all resources that this creator of the public link has access to. This vulnerability is fixed in 2.42.3 and 2.40.3.

Impact

For European organizations, this vulnerability poses a significant risk of unauthorized data disclosure. Since Reva is an interoperability platform used to share and manage resources across cloud environments, exploitation could lead to leakage of sensitive corporate or personal data, violating data protection regulations such as GDPR. The ability to archive all accessible resources via a public link bypasses intended access controls, increasing the risk of intellectual property theft, exposure of confidential business information, or personal data breaches. This could result in reputational damage, regulatory fines, and operational disruption. Organizations using affected versions of Reva in sectors like finance, healthcare, government, or critical infrastructure are particularly at risk due to the sensitivity of their data and the potential impact of unauthorized access. The network-based exploitability and lack of required privileges make this vulnerability attractive to remote attackers, increasing the urgency for mitigation.

CWE-863Incorrect Authorization (opens in a new tab)
Class weaknessLikelihood of exploit: HighCWE Top 25 (2025): #17OWASP Top 10 A01:2025: Broken Access Control (opens in a new tab)
The product performs an authorization check when an actor attempts to access a resource or perform an action, but it does not correctly perform the check.
Architecture and Design
Divide the product into anonymous, normal, privileged, and administrative areas. Reduce the attack surface by carefully mapping roles with data and functionality. Use role-based access control (RBAC) to enforce the roles at the appropriate boundaries.
Architecture and Design
Ensure that access control checks are performed related to the business logic. These checks may be different than the access control checks that are applied to more generic resources such as files, connections, processes, memory, and database records.
Architecture and Design · Libraries or Frameworks
Use a vetted library or framework that does not allow this weakness to occur or provides constructs that make this weakness easier to avoid.
OWASP Cheat Sheets
Authorization (opens in a new tab)
OWASP ASVS 4.0.3
V8.3.8 (opens in a new tab)
V13.4.2 (opens in a new tab)
V7.2.2 (opens in a new tab)
From MITRE CWE, MITRE CAPEC and OWASP (Top 10, OpenCRE).

References

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Exploitation evidence

What to do

Affected software

Description

AI analysisMachine-generated, updated 6 Feb 2026, 19:14 UTC

WeaknessesCWE-863

Technical details

References

Community reviews

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