CVE-2026-21697 (GCVE-0-2026-21697)
Vulnerability from cvelistv5 – Published: 2026-01-07 22:29 – Updated: 2026-01-08 20:37
VLAI
EPSS
VEX
Title
axios4go's Race Condition in Shared HTTP Client Allows Proxy Configuration Leak
Summary
axios4go is a Go HTTP client library. Prior to version 0.6.4, a race condition vulnerability exists in the shared HTTP client configuration. The global `defaultClient` is mutated during request execution without synchronization, directly modifying the shared `http.Client`'s `Transport`, `Timeout`, and `CheckRedirect` properties. Impacted applications include that that use axios4go with concurrent requests (multiple goroutines, `GetAsync`, `PostAsync`, etc.), those where different requests use different proxy configurations, and those that handle sensitive data (authentication credentials, tokens, API keys). Version 0.6.4 fixes this issue.
Severity
SSVC
Exploitation: none
Automatable: yes
Technical Impact: partial
CISA Coordinator · CISA-ADP (v2.0.3)
Decision recorded 2026-01-08 20:37 UTC
CWE
- CWE-362 - Concurrent Execution using Shared Resource with Improper Synchronization ('Race Condition')
Assigner
References
3 references
| URL | Tags |
|---|---|
| https://github.com/rezmoss/axios4go/security/advi… | x_refsource_CONFIRM |
| https://github.com/rezmoss/axios4go/commit/b65160… | x_refsource_MISC |
| https://github.com/rezmoss/axios4go/releases/tag/v0.6.4 | x_refsource_MISC |
Impacted products
{
"containers": {
"adp": [
{
"metrics": [
{
"other": {
"content": {
"id": "CVE-2026-21697",
"options": [
{
"Exploitation": "none"
},
{
"Automatable": "yes"
},
{
"Technical Impact": "partial"
}
],
"role": "CISA Coordinator",
"timestamp": "2026-01-08T20:37:08.423675Z",
"version": "2.0.3"
},
"type": "ssvc"
}
}
],
"providerMetadata": {
"dateUpdated": "2026-01-08T20:37:17.978Z",
"orgId": "134c704f-9b21-4f2e-91b3-4a467353bcc0",
"shortName": "CISA-ADP"
},
"title": "CISA ADP Vulnrichment"
}
],
"cna": {
"affected": [
{
"product": "axios4go",
"vendor": "rezmoss",
"versions": [
{
"status": "affected",
"version": "\u003c 0.6.4"
}
]
}
],
"descriptions": [
{
"lang": "en",
"value": "axios4go is a Go HTTP client library. Prior to version 0.6.4, a race condition vulnerability exists in the shared HTTP client configuration. The global `defaultClient` is mutated during request execution without synchronization, directly modifying the shared `http.Client`\u0027s `Transport`, `Timeout`, and `CheckRedirect` properties. Impacted applications include that that use axios4go with concurrent requests (multiple goroutines, `GetAsync`, `PostAsync`, etc.), those where different requests use different proxy configurations, and those that handle sensitive data (authentication credentials, tokens, API keys). Version 0.6.4 fixes this issue."
}
],
"metrics": [
{
"cvssV4_0": {
"attackComplexity": "LOW",
"attackRequirements": "PRESENT",
"attackVector": "NETWORK",
"baseScore": 8.2,
"baseSeverity": "HIGH",
"privilegesRequired": "NONE",
"subAvailabilityImpact": "NONE",
"subConfidentialityImpact": "NONE",
"subIntegrityImpact": "NONE",
"userInteraction": "NONE",
"vectorString": "CVSS:4.0/AV:N/AC:L/AT:P/PR:N/UI:N/VC:N/VI:H/VA:N/SC:N/SI:N/SA:N",
"version": "4.0",
"vulnAvailabilityImpact": "NONE",
"vulnConfidentialityImpact": "NONE",
"vulnIntegrityImpact": "HIGH"
}
}
],
"problemTypes": [
{
"descriptions": [
{
"cweId": "CWE-362",
"description": "CWE-362: Concurrent Execution using Shared Resource with Improper Synchronization (\u0027Race Condition\u0027)",
"lang": "en",
"type": "CWE"
}
]
}
],
"providerMetadata": {
"dateUpdated": "2026-01-07T22:29:57.393Z",
"orgId": "a0819718-46f1-4df5-94e2-005712e83aaa",
"shortName": "GitHub_M"
},
"references": [
{
"name": "https://github.com/rezmoss/axios4go/security/advisories/GHSA-cmj9-27wj-7x47",
"tags": [
"x_refsource_CONFIRM"
],
"url": "https://github.com/rezmoss/axios4go/security/advisories/GHSA-cmj9-27wj-7x47"
},
{
"name": "https://github.com/rezmoss/axios4go/commit/b651604c64e66a115ab90cdab358b0181d74a842",
"tags": [
"x_refsource_MISC"
],
"url": "https://github.com/rezmoss/axios4go/commit/b651604c64e66a115ab90cdab358b0181d74a842"
},
{
"name": "https://github.com/rezmoss/axios4go/releases/tag/v0.6.4",
"tags": [
"x_refsource_MISC"
],
"url": "https://github.com/rezmoss/axios4go/releases/tag/v0.6.4"
}
],
"source": {
"advisory": "GHSA-cmj9-27wj-7x47",
"discovery": "UNKNOWN"
},
"title": "axios4go\u0027s Race Condition in Shared HTTP Client Allows Proxy Configuration Leak"
}
},
"cveMetadata": {
"assignerOrgId": "a0819718-46f1-4df5-94e2-005712e83aaa",
"assignerShortName": "GitHub_M",
"cveId": "CVE-2026-21697",
"datePublished": "2026-01-07T22:29:57.393Z",
"dateReserved": "2026-01-02T18:45:27.397Z",
"dateUpdated": "2026-01-08T20:37:17.978Z",
"state": "PUBLISHED"
},
"dataType": "CVE_RECORD",
"dataVersion": "5.2",
"vulnerability-lookup:meta": {
"epss": {
"cve": "CVE-2026-21697",
"date": "2026-09-19",
"epss": "0.00413",
"percentile": "0.35303"
},
"nvd": {
"cve": {
"affected": [
{
"affectedData": [
{
"product": "axios4go",
"vendor": "rezmoss",
"versions": [
{
"status": "affected",
"version": "\u003c 0.6.4"
}
]
}
],
"source": "security-advisories@github.com"
}
],
"configurations": [
{
"nodes": [
{
"cpeMatch": [
{
"criteria": "cpe:2.3:a:rezmoss:axios4go:*:*:*:*:*:go:*:*",
"matchCriteriaId": "53BFBFF7-32A9-4C6A-B563-6CABA5301DE5",
"versionEndExcluding": "0.6.4",
"vulnerable": true
}
],
"negate": false,
"operator": "OR"
}
]
}
],
"cveTags": [],
"descriptions": [
{
"lang": "en",
"value": "axios4go is a Go HTTP client library. Prior to version 0.6.4, a race condition vulnerability exists in the shared HTTP client configuration. The global `defaultClient` is mutated during request execution without synchronization, directly modifying the shared `http.Client`\u0027s `Transport`, `Timeout`, and `CheckRedirect` properties. Impacted applications include that that use axios4go with concurrent requests (multiple goroutines, `GetAsync`, `PostAsync`, etc.), those where different requests use different proxy configurations, and those that handle sensitive data (authentication credentials, tokens, API keys). Version 0.6.4 fixes this issue."
},
{
"lang": "es",
"value": "axios4go es una biblioteca cliente HTTP de Go. Antes de la versi\u00f3n 0.6.4, existe una vulnerabilidad de condici\u00f3n de carrera en la configuraci\u00f3n compartida del cliente HTTP. El `defaultClient` global se muta durante la ejecuci\u00f3n de la solicitud sin sincronizaci\u00f3n, modificando directamente las propiedades `Transport`, `Timeout` y `CheckRedirect` del `http.Client` compartido. Las aplicaciones afectadas incluyen aquellas que usan axios4go con solicitudes concurrentes (m\u00faltiples goroutines, `GetAsync`, `PostAsync`, etc.), aquellas donde diferentes solicitudes usan diferentes configuraciones de proxy, y aquellas que manejan datos sensibles (credenciales de autenticaci\u00f3n, tokens, claves API). La versi\u00f3n 0.6.4 corrige este problema."
}
],
"id": "CVE-2026-21697",
"lastModified": "2026-06-17T10:18:56.770",
"metrics": {
"cvssMetricV31": [
{
"cvssData": {
"attackComplexity": "HIGH",
"attackVector": "NETWORK",
"availabilityImpact": "HIGH",
"baseScore": 8.1,
"baseSeverity": "HIGH",
"confidentialityImpact": "HIGH",
"integrityImpact": "HIGH",
"privilegesRequired": "NONE",
"scope": "UNCHANGED",
"userInteraction": "NONE",
"vectorString": "CVSS:3.1/AV:N/AC:H/PR:N/UI:N/S:U/C:H/I:H/A:H",
"version": "3.1"
},
"exploitabilityScore": 2.2,
"impactScore": 5.9,
"source": "nvd@nist.gov",
"type": "Primary"
}
],
"cvssMetricV40": [
{
"cvssData": {
"Automatable": "NOT_DEFINED",
"Recovery": "NOT_DEFINED",
"Safety": "NOT_DEFINED",
"attackComplexity": "LOW",
"attackRequirements": "PRESENT",
"attackVector": "NETWORK",
"availabilityRequirement": "NOT_DEFINED",
"baseScore": 8.2,
"baseSeverity": "HIGH",
"confidentialityRequirement": "NOT_DEFINED",
"exploitMaturity": "NOT_DEFINED",
"integrityRequirement": "NOT_DEFINED",
"modifiedAttackComplexity": "NOT_DEFINED",
"modifiedAttackRequirements": "NOT_DEFINED",
"modifiedAttackVector": "NOT_DEFINED",
"modifiedPrivilegesRequired": "NOT_DEFINED",
"modifiedSubAvailabilityImpact": "NOT_DEFINED",
"modifiedSubConfidentialityImpact": "NOT_DEFINED",
"modifiedSubIntegrityImpact": "NOT_DEFINED",
"modifiedUserInteraction": "NOT_DEFINED",
"modifiedVulnAvailabilityImpact": "NOT_DEFINED",
"modifiedVulnConfidentialityImpact": "NOT_DEFINED",
"modifiedVulnIntegrityImpact": "NOT_DEFINED",
"privilegesRequired": "NONE",
"providerUrgency": "NOT_DEFINED",
"subAvailabilityImpact": "NONE",
"subConfidentialityImpact": "NONE",
"subIntegrityImpact": "NONE",
"userInteraction": "NONE",
"valueDensity": "NOT_DEFINED",
"vectorString": "CVSS:4.0/AV:N/AC:L/AT:P/PR:N/UI:N/VC:N/VI:H/VA:N/SC:N/SI:N/SA:N/E:X/CR:X/IR:X/AR:X/MAV:X/MAC:X/MAT:X/MPR:X/MUI:X/MVC:X/MVI:X/MVA:X/MSC:X/MSI:X/MSA:X/S:X/AU:X/R:X/V:X/RE:X/U:X",
"version": "4.0",
"vulnAvailabilityImpact": "NONE",
"vulnConfidentialityImpact": "NONE",
"vulnIntegrityImpact": "HIGH",
"vulnerabilityResponseEffort": "NOT_DEFINED"
},
"source": "security-advisories@github.com",
"type": "Secondary"
}
],
"ssvcV203": [
{
"source": "134c704f-9b21-4f2e-91b3-4a467353bcc0",
"ssvcData": {
"id": "CVE-2026-21697",
"options": [
{
"exploitation": "none"
},
{
"automatable": "yes"
},
{
"technicalImpact": "partial"
}
],
"role": "CISA Coordinator",
"timestamp": "2026-01-08T20:37:08.423675Z",
"version": "2.0.3"
}
}
]
},
"published": "2026-01-07T23:15:50.533",
"references": [
{
"source": "security-advisories@github.com",
"tags": [
"Patch"
],
"url": "https://github.com/rezmoss/axios4go/commit/b651604c64e66a115ab90cdab358b0181d74a842"
},
{
"source": "security-advisories@github.com",
"tags": [
"Product"
],
"url": "https://github.com/rezmoss/axios4go/releases/tag/v0.6.4"
},
{
"source": "security-advisories@github.com",
"tags": [
"Mitigation",
"Vendor Advisory"
],
"url": "https://github.com/rezmoss/axios4go/security/advisories/GHSA-cmj9-27wj-7x47"
}
],
"sourceIdentifier": "security-advisories@github.com",
"vulnStatus": "Analyzed",
"weaknesses": [
{
"description": [
{
"lang": "en",
"value": "CWE-362"
}
],
"source": "security-advisories@github.com",
"type": "Secondary"
}
]
}
},
"redhat_vex": {
"current_release_date": "2026-01-09T08:38:13+00:00",
"cve": "CVE-2026-21697",
"id": "CVE-2026-21697",
"initial_release_date": "2026-01-01T00:00:00+00:00",
"product_status:known_not_affected": "1",
"source": "Red Hat CSAF VEX",
"status": "final",
"title": "axios4go\u0027s Race Condition in Shared HTTP Client Allows Proxy Configuration Leak",
"url": "https://security.access.redhat.com/data/csaf/v2/vex/2026/cve-2026-21697.json",
"version": "3"
},
"vulnrichment": {
"containers": {
"adp": [
{
"metrics": [
{
"other": {
"content": {
"id": "CVE-2026-21697",
"options": [
{
"Exploitation": "none"
},
{
"Automatable": "yes"
},
{
"Technical Impact": "partial"
}
],
"role": "CISA Coordinator",
"timestamp": "2026-01-08T20:37:08.423675Z",
"version": "2.0.3"
},
"type": "ssvc"
}
}
],
"providerMetadata": {
"dateUpdated": "2026-01-08T20:37:12.742Z",
"orgId": "134c704f-9b21-4f2e-91b3-4a467353bcc0",
"shortName": "CISA-ADP"
},
"title": "CISA ADP Vulnrichment"
}
],
"cna": {
"affected": [
{
"product": "axios4go",
"vendor": "rezmoss",
"versions": [
{
"status": "affected",
"version": "\u003c 0.6.4"
}
]
}
],
"descriptions": [
{
"lang": "en",
"value": "axios4go is a Go HTTP client library. Prior to version 0.6.4, a race condition vulnerability exists in the shared HTTP client configuration. The global `defaultClient` is mutated during request execution without synchronization, directly modifying the shared `http.Client`\u0027s `Transport`, `Timeout`, and `CheckRedirect` properties. Impacted applications include that that use axios4go with concurrent requests (multiple goroutines, `GetAsync`, `PostAsync`, etc.), those where different requests use different proxy configurations, and those that handle sensitive data (authentication credentials, tokens, API keys). Version 0.6.4 fixes this issue."
}
],
"metrics": [
{
"cvssV4_0": {
"attackComplexity": "LOW",
"attackRequirements": "PRESENT",
"attackVector": "NETWORK",
"baseScore": 8.2,
"baseSeverity": "HIGH",
"privilegesRequired": "NONE",
"subAvailabilityImpact": "NONE",
"subConfidentialityImpact": "NONE",
"subIntegrityImpact": "NONE",
"userInteraction": "NONE",
"vectorString": "CVSS:4.0/AV:N/AC:L/AT:P/PR:N/UI:N/VC:N/VI:H/VA:N/SC:N/SI:N/SA:N",
"version": "4.0",
"vulnAvailabilityImpact": "NONE",
"vulnConfidentialityImpact": "NONE",
"vulnIntegrityImpact": "HIGH"
}
}
],
"problemTypes": [
{
"descriptions": [
{
"cweId": "CWE-362",
"description": "CWE-362: Concurrent Execution using Shared Resource with Improper Synchronization (\u0027Race Condition\u0027)",
"lang": "en",
"type": "CWE"
}
]
}
],
"providerMetadata": {
"dateUpdated": "2026-01-07T22:29:57.393Z",
"orgId": "a0819718-46f1-4df5-94e2-005712e83aaa",
"shortName": "GitHub_M"
},
"references": [
{
"name": "https://github.com/rezmoss/axios4go/security/advisories/GHSA-cmj9-27wj-7x47",
"tags": [
"x_refsource_CONFIRM"
],
"url": "https://github.com/rezmoss/axios4go/security/advisories/GHSA-cmj9-27wj-7x47"
},
{
"name": "https://github.com/rezmoss/axios4go/commit/b651604c64e66a115ab90cdab358b0181d74a842",
"tags": [
"x_refsource_MISC"
],
"url": "https://github.com/rezmoss/axios4go/commit/b651604c64e66a115ab90cdab358b0181d74a842"
},
{
"name": "https://github.com/rezmoss/axios4go/releases/tag/v0.6.4",
"tags": [
"x_refsource_MISC"
],
"url": "https://github.com/rezmoss/axios4go/releases/tag/v0.6.4"
}
],
"source": {
"advisory": "GHSA-cmj9-27wj-7x47",
"discovery": "UNKNOWN"
},
"title": "axios4go\u0027s Race Condition in Shared HTTP Client Allows Proxy Configuration Leak"
}
},
"cveMetadata": {
"assignerOrgId": "a0819718-46f1-4df5-94e2-005712e83aaa",
"assignerShortName": "GitHub_M",
"cveId": "CVE-2026-21697",
"datePublished": "2026-01-07T22:29:57.393Z",
"dateReserved": "2026-01-02T18:45:27.397Z",
"dateUpdated": "2026-01-08T20:37:17.978Z",
"state": "PUBLISHED"
},
"dataType": "CVE_RECORD",
"dataVersion": "5.2"
}
}
}
Loading…
Loading…
Experimental. This forecast is provided for visualization only and may change without notice. Do not use it for operational decisions.
Forecast uses a logistic model when the trend is rising, or an exponential decay model when the trend is falling. Fitted via linearized least squares.
Sightings
| Author | Source | Type | Date | Other |
|---|
Nomenclature
- Seen: The vulnerability was mentioned, discussed, or observed by the user.
- Confirmed: The vulnerability has been validated from an analyst's perspective.
- Published Proof of Concept: A public proof of concept is available for this vulnerability.
- Exploited: The vulnerability was observed as exploited by the user who reported the sighting.
- Patched: The vulnerability was observed as successfully patched by the user who reported the sighting.
- Not exploited: The vulnerability was not observed as exploited by the user who reported the sighting.
- Not confirmed: The user expressed doubt about the validity of the vulnerability.
- Not patched: The vulnerability was not observed as successfully patched by the user who reported the sighting.
Loading…
The MITRE ATT&CK techniques below are AI-generated suggestions, inferred from the description of the
vulnerability by the CIRCL/vulnerability-attack-technique-classification-roberta-base
model, served locally by ML-Gateway.
They have not been verified by an analyst and are provided for guidance only.
The approach is described in our paper Mapping CVEs to MITRE ATT&CK Techniques: A Curated Gold-Set Classifier and the Limits of LLM-Assisted Label Expansion.
Browse all ATT&CK techniques and the vulnerabilities related to each.
The approach is described in our paper Mapping CVEs to MITRE ATT&CK Techniques: A Curated Gold-Set Classifier and the Limits of LLM-Assisted Label Expansion.
Browse all ATT&CK techniques and the vulnerabilities related to each.
Loading…
Related by attack behaviour
Vulnerabilities whose description is nearest to this one in the vector space of the CIRCL/vulnerability-attack-technique-biencoder model. This is a similarity search over the bi-encoder space (plain cosine), not a classification, and it has no measured accuracy.
Loading…