VulnerabilityPublished 11 Mar 2026

CVE-2026-32101: @studiocms s3-storage · Incorrect Authorization

Affects @studiocms s3-storageSource CVE Database V5

Compare

Not known to be exploited · CVSS 7.6 High : upgrade to 0.3.1 soon.

Data as of 30 Oct 2026, 11:52 UTC

CVSS 3.1 base score

7.6High

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

EPSS: 0.1% chance of exploitation in 30 days – higher than 9% of CVEsExploit Prediction Scoring System: the likelihood attackers will use this flaw soon.
Patch: Available – fixed in 0.3.1

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

Attack Vector: Network
Attack Complexity: Low
Privileges Required: Low
User Interaction: None
Scope: Unchanged
Confidentiality: Low
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: Low: Specialized access conditions or extenuating circumstances do not exist. An attacker can expect repeatable success against the vulnerable component.
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: 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: 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 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 11 Mar 2026
Detectable: no evidence on record.
No public nuclei template indexed
Weaponized: 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 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

Upgrade @studiocms s3-storage to 0.3.1.

Affected software

Product	Affected	Fixed in
@studiocmss3-storage	Affected <0.3.1	Fixed in 0.3.1

AI-suggested

Organizations should immediately upgrade the @studiocms s3-storage manager to version 0.3.1 or later, where the authorization bypass is fixed by correctly awaiting the asynchronous isAuthorized() function. Until upgrading, restrict access to the CMS to trusted users only and monitor S3 bucket activity for unauthorized file operations. Implement additional access controls at the S3 bucket policy level to limit file operations to authorized service accounts. Conduct code reviews to ensure all asynchronous authorization checks are properly awaited in custom or forked versions. Employ runtime monitoring and alerting for anomalous file operations. Regularly audit user roles and permissions within StudioCMS to minimize the number of users with authenticated access. Consider isolating the CMS environment and S3 buckets behind network segmentation and VPNs to reduce exposure.

Description

CVE-2026-32101 is a high-severity authorization bypass vulnerability in the @studiocms s3-storage manager versions prior to 0.3.1. The flaw arises because the asynchronous isAuthorized() function is called without awaiting its Promise result, causing the authorization check to always pass. This allows any authenticated user with the lowest visitor role to perform unauthorized file operations such as upload, delete, rename, and list on the S3 bucket. The vulnerability affects server-side-rendered, Astro native, headless CMS deployments using vulnerable versions of the s3-storage manager. No user interaction is required beyond authentication, and the vulnerability is remotely exploitable over the network. The issue is fixed in version 0.3.1.

Impact

The vulnerability allows any authenticated user with minimal privileges to bypass authorization controls and manipulate files in the S3 bucket used by StudioCMS. This can lead to unauthorized data modification, deletion, or addition, undermining data integrity. Attackers could deface websites, inject malicious content, or disrupt service availability by deleting or renaming critical files. Confidentiality impact is limited since the attacker must be authenticated, but integrity and availability impacts are high. Organizations relying on StudioCMS for content delivery or storage could face reputational damage, data loss, and service disruption. The ease of exploitation and network accessibility increase the risk of widespread abuse if not promptly mitigated.

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

github.com/withstudiocms/studiocms/security/advisories/GHSA-mm78-fgq8-6pgr (opens in a new tab)

Community reviews

Loading reviews…

Exploitation evidence

What to do

Affected software

Description

AI analysisMachine-generated, updated 19 Mar 2026, 02:20 UTC

WeaknessesCWE-863

Technical details

References

Community reviews

Related threats