VulnerabilityPublished 4 Jun 2025

CVE-2025-48935: denoland deno · Incorrect Authorization

Affects denoland denoSource CVE Database V5

Public exploit available · CVSS 5.5 Medium : upgrade to 2.2.5 as a priority.

Data as of 26 Oct 2026, 10:12 UTC

CVSS 4.0 base score

5.5Medium

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.
Patch: Available – fixed in 2.2.5

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

Base metrics

Attack Vector: Network
Attack Complexity: Low
Attack Requirements: None
Privileges Required: None
User Interaction: None
Vulnerable system confidentiality: None
Vulnerable system integrity: Low
Vulnerable system availability: None
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: 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: None: There is no loss of confidentiality within 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: 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.
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 4 Jun 2025
Detectable: no evidence on record.
No public nuclei template indexed
Weaponised: 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 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

Upgrade denoland/deno to 2.2.5.

Affected software

Product	Affected	Fixed in
GitHubdenoland/deno`pkg:github/denoland/deno`Other threats	Affected >=2.2.0 <2.2.5	Fixed in 2.2.5

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 take the following specific actions to mitigate this vulnerability: 1) Identify all instances of Deno runtime in use, including development, testing, and production environments, with a focus on versions between 2.2.0 and 2.2.4 inclusive. 2) Upgrade all affected Deno installations to version 2.2.5 or later, which contains the patch that enforces proper permission checks on database attachment operations. 3) Review and audit permission configurations in Deno applications to ensure the principle of least privilege is applied, minimizing granted read/write permissions to only necessary resources. 4) Implement runtime monitoring and logging for database access operations within Deno applications to detect anomalous or unauthorized attachment attempts. 5) For environments where immediate patching is not feasible, consider restricting network access to Deno services and applying application-layer controls to limit execution of untrusted code. 6) Educate developers and DevOps teams about the importance of applying security patches promptly and verifying permission enforcement in Deno-based applications. 7) Incorporate this vulnerability into vulnerability management and incident response plans to ensure rapid detection and remediation if exploitation attempts occur.

Description

Deno is a JavaScript, TypeScript, and WebAssembly runtime. Starting in version 2.2.0 and prior to versions 2.2.5, it is possible to bypass Deno's permission read/write db permission check by using `ATTACH DATABASE` statement. Version 2.2.5 contains a patch for the issue.

Impact

For European organizations, the impact of this vulnerability depends largely on the extent to which Deno is used in their technology stacks, particularly in environments handling sensitive data or critical applications. Organizations using Deno to run backend services, APIs, or automation scripts that interact with databases could face unauthorized data access or modification risks if they run vulnerable versions. This could lead to data integrity issues, potential data leakage, or unauthorized data manipulation. Since Deno is often chosen for its security model, this vulnerability undermines that trust and could expose organizations to compliance risks, especially under GDPR where unauthorized data access must be prevented. The vulnerability could also be leveraged as part of a larger attack chain to escalate privileges or move laterally within a network if an attacker gains initial code execution. However, the medium severity and lack of known exploits suggest the immediate risk is moderate, but organizations should prioritize patching to maintain a strong security posture.

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

Community reviews

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Exploitation evidence

What to do

Affected software

Description

AI analysisMachine-generated, updated 7 Jul 2025, 02:42 UTC

WeaknessesCWE-863

Technical details

References

Community reviews

Related threats