VulnerabilityPublished 3 Jun 2025

CVE-2025-24015: denoland deno · Improper Verification of Cryptographic Signature

Affects denoland denoSource CVE Database V5

Public exploit available · CVSS 7.7 High · fixed in 2.1.7 : patch denoland deno as a priority.

Data as of 26 Oct 2026, 14:05 UTC

CVSS 4.0 base score

7.7High

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

EPSS: 0.2% chance of exploitation in 30 days – higher than 19% of CVEsExploit Prediction Scoring System: the likelihood attackers will use this flaw soon.
Patch: Available – fixed in 2.1.7

CVSS:4.0/AV:N/AC:L/AT:N/PR:N/UI:N/VC:N/VI:H/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: High
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: 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.
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 3 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

Affected software

Product	Affected	Fixed in
GitHubdenoland/deno`pkg:github/denoland/deno`Other threats	Affected =1.46.0 <=2.1.6	Fixed in–

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 assess their use of Deno runtime versions between 1.46.0 and 2.1.6. The primary mitigation is to upgrade all affected Deno instances to version 2.1.7 or later, where the authentication tag verification issue is patched. Until upgrades can be performed, organizations should consider disabling or avoiding the use of AES-GCM encryption within Deno or implement additional application-level integrity checks as a temporary safeguard. Security teams should audit cryptographic usage in their codebases to identify reliance on AES-GCM and verify that authentication tags are properly validated. Incorporating cryptographic libraries with proven and tested implementations or fallback mechanisms may reduce risk. Monitoring network traffic and application logs for anomalies related to encrypted data manipulation can help detect exploitation attempts. Additionally, organizations should review their incident response plans to handle potential data integrity breaches. Vendor communication channels and security advisories from denoland should be monitored for further updates or exploit disclosures. Finally, developers should be trained on the importance of cryptographic validation and the risks of improper implementation to prevent similar issues in the future.

Description

Deno is a JavaScript, TypeScript, and WebAssembly runtime. Versions 1.46.0 through 2.1.6 have an issue that affects AES-256-GCM and AES-128-GCM in Deno in which the authentication tag is not being validated. This means tampered ciphertexts or incorrect keys might not be detected, which breaks the guarantees expected from AES-GCM. Older versions of Deno correctly threw errors in such cases, as does Node.js. Without authentication tag verification, AES-GCM degrades to essentially CTR mode, removing integrity protection. Authenticated data set with set_aad is also affected, as it is incorporated into the GCM hash (ghash) but this too is not validated, rendering AAD checks ineffective. Version 2.1.7 includes a patch that addresses this issue.

Impact

For European organizations using Deno in their development or production environments, this vulnerability poses a significant risk to data integrity and authenticity. Applications relying on AES-GCM encryption for securing sensitive data, communications, or tokens may be vulnerable to undetected ciphertext tampering or key misuse. This could lead to unauthorized data manipulation, injection of malicious payloads, or bypassing of security controls that depend on cryptographic assurances. Since Deno is often used in modern web services, microservices, and serverless functions, the impact could extend to critical business applications, APIs, and cloud-native deployments. The lack of authentication tag verification undermines trust in encrypted data, potentially exposing organizations to data corruption, fraud, or compliance violations related to data protection regulations such as GDPR. Moreover, attackers could exploit this flaw remotely without authentication or user interaction, increasing the threat surface. While no active exploits are known, the high severity and ease of exploitation warrant urgent attention. The impact on confidentiality is moderate since encryption still occurs, but integrity and authenticity are severely compromised, which can have cascading effects on application logic and security.

CWE-347Improper Verification of Cryptographic Signature (opens in a new tab)
Base weaknessOWASP Top 10 A04:2025: Cryptographic Failures (opens in a new tab)
The product does not verify, or incorrectly verifies, the cryptographic signature for data.
OWASP Cheat Sheets
XML Security (opens in a new tab)
REST Security (opens in a new tab)
JSON Web Token for Java (opens in a new tab)
REST Assessment (opens in a new tab)
Cross-Site Request Forgery Prevention (opens in a new tab)
OWASP ASVS 4.0.3
V13.3.2 (opens in a new tab)
V3.5.3 (opens in a new tab)
V13.2.6 (opens in a new tab)
Attack patterns
Padding Oracle Crypto Attack (opens in a new tab)
Signature Spoofing by Improper Validation (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 4 Jul 2025, 19:56 UTC

WeaknessesCWE-347

Technical details

References

Community reviews

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