VulnerabilityPublished 31 Mar 2026

CVE-2026-34532: parse-server · Incorrect Authorization

Affects parse-serverSource CVE Database V5

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Not known to be exploited · CVSS 9.1 Critical : upgrade to 9.7.0-alpha.11 or 8.6.67 as a priority.

Data as of 30 Oct 2026, 11:52 UTC

CVSS 4.0 base score

9.1Critical

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

Contested

Critical score, yet low EPSS after six months

EPSS: 0.2% chance of exploitation in 30 days – higher than 20% of CVEsExploit Prediction Scoring System: the likelihood attackers will use this flaw soon.
Patch: Available – fixed in 9.7.0-alpha.11, 8.6.67

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

Attack Vector: Network
Attack Complexity: Low
Attack Requirements: Present
Privileges Required: None
User Interaction: None
Vulnerable system confidentiality: High
Vulnerable system integrity: High
Vulnerable system availability: None
Subsequent system confidentiality: None
Subsequent system integrity: None
Subsequent system availability: None

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: Present: The successful attack depends on the presence of specific deployment and execution conditions of the vulnerable system that enable the attack. These include: a race condition must be won to successfully exploit the vulnerability (the successfulness of the attack is conditioned on execution conditions that are not under full control of the attacker, or the attack may need to be launched multiple times against a single target before being successful); the attacker must inject themselves into the logical network path between the target and the resource requested by the victim (e.g. vulnerabilities requiring an on-path attacker).
Privileges Required: None: The attacker is unauthorized prior to attack, and therefore does not require any access to settings or files of the vulnerable system to carry out an attack.
User Interaction: None: The vulnerable system can be exploited without interaction from any human user, other than the attacker.
Vulnerable system confidentiality: High: There is a total loss of confidentiality, resulting in all information within the Vulnerable System being divulged to the attacker. Alternatively, access to only some restricted information is obtained, but the disclosed information presents a direct, serious impact. For example, an attacker steals the administrator's password, or private encryption keys of a web server.
Vulnerable system 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 vulnerable system. Alternatively, only some files can be modified, but malicious modification would present a direct, serious consequence to the vulnerable system.
Vulnerable system availability: None: There is no impact to availability within 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.

Definitions: FIRST CVSS v4.0 specification.

Exploitation evidence

Disclosed: evidence found.
CVE published 31 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 parse-server to 9.7.0-alpha.11 or 8.6.67; parse-community/parse-server to 8.6.67.

Affected software

Product	Affected	Fixed in
parse-communityparse-server	Affected >=9.0.0 <9.7.0-alpha.11	Fixed in 9.7.0-alpha.11
parse-communityparse-server	Affected <8.6.67	Fixed in 8.6.67
npmparse-community/parse-server`pkg:npm/parse-community/parse-server`Other threats	Affected <8.6.67	Fixed in 8.6.67

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

AI-suggested

Organizations should immediately upgrade parse-server to version 8.6.67 or later, or to 9.7.0-alpha.11 or later, where the vulnerability is patched. In addition to upgrading, review all Cloud Functions and their validators to ensure they do not rely on vulnerable patterns such as function keyword declarations with plain object or arrow function validators. Implement strict input validation and URL sanitization to detect and block attempts to append prototype chain traversal strings like "prototype.constructor". Employ runtime application self-protection (RASP) or web application firewalls (WAFs) with custom rules to detect anomalous URL patterns targeting Cloud Functions. Conduct thorough security testing, including penetration testing focused on authorization bypass scenarios. Monitor logs for suspicious access patterns to Cloud Functions, especially those invoked without authentication. Finally, maintain an up-to-date inventory of parse-server versions deployed across environments to ensure timely patching.

Description

Parse Server is an open source backend that can be deployed to any infrastructure that can run Node.js. Prior to versions 8.6.67 and 9.7.0-alpha.11, an attacker can bypass Cloud Function validator access controls by appending "prototype.constructor" to the function name in the URL. When a Cloud Function handler is declared using the function keyword and its validator is a plain object or arrow function, the trigger store traversal resolves the handler through its own prototype chain while the validator store fails to mirror this traversal, causing all access control enforcement to be skipped. This allows unauthenticated callers to invoke Cloud Functions that are meant to be protected by validators such as requireUser, requireMaster, or custom validation logic. This issue has been patched in versions 8.6.67 and 9.7.0-alpha.11.

Impact

The vulnerability allows unauthenticated attackers to bypass critical access controls on Cloud Functions within parse-server, potentially leading to unauthorized execution of backend logic. This can result in unauthorized data access, modification, or deletion, compromising confidentiality and integrity of data managed by the affected applications. Since Cloud Functions often handle sensitive operations such as user authentication, data processing, or administrative tasks, exploitation could lead to privilege escalation, data breaches, or service manipulation. The lack of required authentication and user interaction lowers the barrier for attackers, increasing the likelihood of exploitation. Organizations relying on parse-server for backend services may face severe operational and reputational damage if this vulnerability is exploited, especially in environments handling sensitive or regulated data.

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 31 Mar 2026, 15:08 UTC

WeaknessesCWE-863

Technical details

References

Community reviews

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