VulnerabilityPublished 5 May 2026

CVE-2026-42033: Axios · Prototype Pollution Gadgets - Response Tampering, Data Exfiltration, and Request Hijacking

Affects axiosSource GCVE Database

Not known to be exploited · CVSS 7.4 High : upgrade to 1.15.1 soon.

Data as of 27 Oct 2026, 01:30 UTC

CVSS 3.1 base score

7.4High

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

Patch: Available – fixed in 1.15.1, 0.31.1

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

Attack Vector: Network
Attack Complexity: High
Privileges Required: None
User Interaction: None
Scope: Unchanged
Confidentiality: High
Integrity: High
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: High: A successful attack depends on conditions beyond the attacker's control. That is, a successful attack cannot be accomplished at will, but requires the attacker to invest in some measurable amount of effort in preparation or execution against the vulnerable component before a successful attack can be expected. For example, a successful attack may require an attacker to: gather knowledge about the environment in which the vulnerable target/component exists; prepare the target environment to improve exploit reliability; or inject themselves into the logical network path between the target and the resource requested by the victim in order to read and/or modify network communications (e.g., a man in the middle attack).
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: 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: None: There is no impact to availability within the impacted component.

Definitions: FIRST CVSS v3.1 specification.

Exploitation evidence

Disclosed: evidence found.
CVE published 5 May 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 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 axios to 1.15.1; axios to 0.31.1.

Affected software

Product	Affected	Fixed in
npmaxios	Affected >=1.0.0 <1.15.1	Fixed in 1.15.1
npmaxios	Affected <0.31.1	Fixed in 0.31.1

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

AI-suggested

A patch is available and should be applied by upgrading axios to version 1.15.1 or later, or 0.31.1 or later. Since the vulnerability depends on prototype pollution from other dependencies, ensure all dependencies such as lodash are also updated to versions that fix prototype pollution vectors (e.g., lodash >= 4.17.21). No other mitigations are indicated by the vendor advisory.

Description

Axios versions from 1.0.0 up to 1.15.0 and versions below 0.31.1 are vulnerable to prototype pollution gadgets that allow attackers to tamper with JSON responses and hijack HTTP requests. This occurs when Object.prototype is polluted by a co-dependency, enabling attackers to intercept and modify JSON responses or hijack HTTP transport to access request credentials and data. The vulnerability arises because axios merges configuration objects without guarding against inherited properties, allowing polluted prototype properties to influence behavior such as JSON parsing via a malicious parseReviver function. A fix is available in versions 1.15.1 and 0.31.1.

Impact

An attacker who can cause prototype pollution in the same process as axios can exploit this vulnerability to silently intercept and modify all JSON responses before the application processes them, potentially exfiltrating sensitive data. Additionally, the attacker can hijack the underlying HTTP transport, gaining access to request credentials, headers, and body data. This compromises confidentiality and integrity of data handled by axios in affected versions.

Summary

This vulnerability (CVE-2026-42033) affects axios when Object.prototype is polluted by a co-dependency with keys that axios reads without hasOwnProperty checks. The merged config object inherits from Object.prototype, and keys absent from own properties fall through to the prototype chain. Specifically, the parseReviver property is accessed during JSON.parse of response data without being an own property, allowing an attacker-controlled function on Object.prototype to intercept and modify every JSON response or hijack HTTP requests. The vulnerability requires prior prototype pollution from another package (e.g., lodash < 4.17.21). Confirmed gadgets include response tampering and request hijacking. The affected versions are >=1.0.0 <1.15.1 and <0.31.1, with fixes in 1.15.1 and 0.31.1. The CVSS 3.1 score is 7.4 (High) with network attack vector, high complexity, no privileges required, no user interaction, and high confidentiality and integrity impact.

CWE-1321Improperly Controlled Modification of Object Prototype Attributes ('Prototype Pollution') (opens in a new tab)
Variant weakness
The product receives input from an upstream component that specifies attributes that are to be initialized or updated in an object, but it does not properly control modifications of attributes of the object prototype.
Implementation
By freezing the object prototype first (for example, Object.freeze(Object.prototype)), modification of the prototype becomes impossible.
Architecture and Design
By blocking modifications of attributes that resolve to object prototype, such as proto or prototype, this weakness can be mitigated.
Implementation · Input Validation
When handling untrusted objects, validating using a schema can be used.
OWASP Cheat Sheets
Mass Assignment (opens in a new tab)
OWASP ASVS 4.0.3
V5.1.2 (opens in a new tab)
Attack patterns
Accessing Functionality Not Properly Constrained by ACLs (opens in a new tab)
Exploiting Incorrectly Configured Access Control Security Levels (opens in a new tab)
Manipulating User-Controlled Variables (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 27 Oct 2026, 01:30 UTC

WeaknessesCWE-1321

Technical details

References

Community reviews

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