CVE-2021-46872 (GCVE-0-2021-46872)
Vulnerability from cvelistv5 – Published: 2023-01-13 00:00 – Updated: 2025-04-07 19:13
VLAI
EPSS
VEX
Summary
An issue was discovered in Nim before 1.6.2. The RST module of the Nim language stdlib, as used in NimForum and other products, permits the javascript: URI scheme and thus can lead to XSS in some applications. (Nim versions 1.6.2 and later are fixed; there may be backports of the fix to some earlier versions. NimForum 2.2.0 is fixed.)
Severity
6.1 (Medium)
SSVC
Exploitation: none
Automatable: no
Technical Impact: partial
CISA Coordinator · CISA-ADP (v2.0.3)
Decision recorded 2025-04-07 19:12 UTC
CWE
- n/a
- CWE-79 - Improper Neutralization of Input During Web Page Generation ('Cross-site Scripting')
Assigner
References
{
"containers": {
"adp": [
{
"providerMetadata": {
"dateUpdated": "2024-08-04T05:17:42.923Z",
"orgId": "af854a3a-2127-422b-91ae-364da2661108",
"shortName": "CVE"
},
"references": [
{
"tags": [
"x_transferred"
],
"url": "https://github.com/nim-lang/nimforum"
},
{
"tags": [
"x_transferred"
],
"url": "https://forum.nim-lang.org/t/8852"
},
{
"tags": [
"x_transferred"
],
"url": "https://github.com/nim-lang/Nim/pull/19134"
},
{
"tags": [
"x_transferred"
],
"url": "https://github.com/nim-lang/Nim/compare/v1.6.0...v1.6.2"
},
{
"tags": [
"x_transferred"
],
"url": "https://github.com/nim-lang/Nim/commit/46275126b89218e64844eee169e8ced05dd0e2d7"
}
],
"title": "CVE Program Container"
},
{
"metrics": [
{
"cvssV3_1": {
"attackComplexity": "LOW",
"attackVector": "NETWORK",
"availabilityImpact": "NONE",
"baseScore": 6.1,
"baseSeverity": "MEDIUM",
"confidentialityImpact": "LOW",
"integrityImpact": "LOW",
"privilegesRequired": "NONE",
"scope": "CHANGED",
"userInteraction": "REQUIRED",
"vectorString": "CVSS:3.1/AV:N/AC:L/PR:N/UI:R/S:C/C:L/I:L/A:N",
"version": "3.1"
}
},
{
"other": {
"content": {
"id": "CVE-2021-46872",
"options": [
{
"Exploitation": "none"
},
{
"Automatable": "no"
},
{
"Technical Impact": "partial"
}
],
"role": "CISA Coordinator",
"timestamp": "2025-04-07T19:12:45.568123Z",
"version": "2.0.3"
},
"type": "ssvc"
}
}
],
"problemTypes": [
{
"descriptions": [
{
"cweId": "CWE-79",
"description": "CWE-79 Improper Neutralization of Input During Web Page Generation (\u0027Cross-site Scripting\u0027)",
"lang": "en",
"type": "CWE"
}
]
}
],
"providerMetadata": {
"dateUpdated": "2025-04-07T19:13:15.282Z",
"orgId": "134c704f-9b21-4f2e-91b3-4a467353bcc0",
"shortName": "CISA-ADP"
},
"title": "CISA ADP Vulnrichment"
}
],
"cna": {
"affected": [
{
"product": "n/a",
"vendor": "n/a",
"versions": [
{
"status": "affected",
"version": "n/a"
}
]
}
],
"descriptions": [
{
"lang": "en",
"value": "An issue was discovered in Nim before 1.6.2. The RST module of the Nim language stdlib, as used in NimForum and other products, permits the javascript: URI scheme and thus can lead to XSS in some applications. (Nim versions 1.6.2 and later are fixed; there may be backports of the fix to some earlier versions. NimForum 2.2.0 is fixed.)"
}
],
"problemTypes": [
{
"descriptions": [
{
"description": "n/a",
"lang": "en",
"type": "text"
}
]
}
],
"providerMetadata": {
"dateUpdated": "2023-01-13T00:00:00.000Z",
"orgId": "8254265b-2729-46b6-b9e3-3dfca2d5bfca",
"shortName": "mitre"
},
"references": [
{
"url": "https://github.com/nim-lang/nimforum"
},
{
"url": "https://forum.nim-lang.org/t/8852"
},
{
"url": "https://github.com/nim-lang/Nim/pull/19134"
},
{
"url": "https://github.com/nim-lang/Nim/compare/v1.6.0...v1.6.2"
},
{
"url": "https://github.com/nim-lang/Nim/commit/46275126b89218e64844eee169e8ced05dd0e2d7"
}
]
}
},
"cveMetadata": {
"assignerOrgId": "8254265b-2729-46b6-b9e3-3dfca2d5bfca",
"assignerShortName": "mitre",
"cveId": "CVE-2021-46872",
"datePublished": "2023-01-13T00:00:00.000Z",
"dateReserved": "2023-01-13T00:00:00.000Z",
"dateUpdated": "2025-04-07T19:13:15.282Z",
"state": "PUBLISHED"
},
"dataType": "CVE_RECORD",
"dataVersion": "5.1",
"vulnerability-lookup:meta": {
"epss": {
"cve": "CVE-2021-46872",
"date": "2026-10-14",
"epss": "0.00537",
"percentile": "0.43895"
},
"nvd": {
"cve": {
"affected": [
{
"affectedData": [
{
"product": "n/a",
"vendor": "n/a",
"versions": [
{
"status": "affected",
"version": "n/a"
}
]
}
],
"source": "cve@mitre.org"
}
],
"configurations": [
{
"nodes": [
{
"cpeMatch": [
{
"criteria": "cpe:2.3:a:nim-lang:nim:*:*:*:*:*:*:*:*",
"matchCriteriaId": "1693ADAF-84A1-4F3D-8C13-C6495A1D91D5",
"versionEndExcluding": "1.6.2",
"vulnerable": true
},
{
"criteria": "cpe:2.3:a:nim-lang:nimforum:*:*:*:*:*:nim:*:*",
"matchCriteriaId": "FE0421BD-56F6-4822-B2F4-B7B31071BC57",
"versionEndExcluding": "2.2.0",
"vulnerable": true
}
],
"negate": false,
"operator": "OR"
}
]
}
],
"cveTags": [],
"descriptions": [
{
"lang": "en",
"value": "An issue was discovered in Nim before 1.6.2. The RST module of the Nim language stdlib, as used in NimForum and other products, permits the javascript: URI scheme and thus can lead to XSS in some applications. (Nim versions 1.6.2 and later are fixed; there may be backports of the fix to some earlier versions. NimForum 2.2.0 is fixed.)"
},
{
"lang": "es",
"value": "Se descubri\u00f3 un problema en Nim antes de la versi\u00f3n 1.6.2. El m\u00f3dulo RST del lenguaje Nim stdlib, tal como se usa en NimForum y otros productos, permite el esquema javascript: URI y, por lo tanto, puede conducir a XSS en algunas aplicaciones. (Las versiones 1.6.2 y posteriores de Nim est\u00e1n corregidas; puede haber versiones anteriores de la soluci\u00f3n para algunas versiones anteriores. NimForum 2.2.0 est\u00e1 corregida)."
}
],
"id": "CVE-2021-46872",
"lastModified": "2026-06-17T04:15:41.963",
"metrics": {
"cvssMetricV31": [
{
"cvssData": {
"attackComplexity": "LOW",
"attackVector": "NETWORK",
"availabilityImpact": "NONE",
"baseScore": 6.1,
"baseSeverity": "MEDIUM",
"confidentialityImpact": "LOW",
"integrityImpact": "LOW",
"privilegesRequired": "NONE",
"scope": "CHANGED",
"userInteraction": "REQUIRED",
"vectorString": "CVSS:3.1/AV:N/AC:L/PR:N/UI:R/S:C/C:L/I:L/A:N",
"version": "3.1"
},
"exploitabilityScore": 2.8,
"impactScore": 2.7,
"source": "nvd@nist.gov",
"type": "Primary"
},
{
"cvssData": {
"attackComplexity": "LOW",
"attackVector": "NETWORK",
"availabilityImpact": "NONE",
"baseScore": 6.1,
"baseSeverity": "MEDIUM",
"confidentialityImpact": "LOW",
"integrityImpact": "LOW",
"privilegesRequired": "NONE",
"scope": "CHANGED",
"userInteraction": "REQUIRED",
"vectorString": "CVSS:3.1/AV:N/AC:L/PR:N/UI:R/S:C/C:L/I:L/A:N",
"version": "3.1"
},
"exploitabilityScore": 2.8,
"impactScore": 2.7,
"source": "134c704f-9b21-4f2e-91b3-4a467353bcc0",
"type": "Secondary"
}
],
"ssvcV203": [
{
"source": "134c704f-9b21-4f2e-91b3-4a467353bcc0",
"ssvcData": {
"id": "CVE-2021-46872",
"options": [
{
"exploitation": "none"
},
{
"automatable": "no"
},
{
"technicalImpact": "partial"
}
],
"role": "CISA Coordinator",
"timestamp": "2025-04-07T19:12:45.568123Z",
"version": "2.0.3"
}
}
]
},
"published": "2023-01-13T06:15:10.940",
"references": [
{
"source": "cve@mitre.org",
"tags": [
"Issue Tracking",
"Vendor Advisory"
],
"url": "https://forum.nim-lang.org/t/8852"
},
{
"source": "cve@mitre.org",
"tags": [
"Patch",
"Third Party Advisory"
],
"url": "https://github.com/nim-lang/Nim/commit/46275126b89218e64844eee169e8ced05dd0e2d7"
},
{
"source": "cve@mitre.org",
"tags": [
"Third Party Advisory"
],
"url": "https://github.com/nim-lang/Nim/compare/v1.6.0...v1.6.2"
},
{
"source": "cve@mitre.org",
"tags": [
"Patch",
"Third Party Advisory"
],
"url": "https://github.com/nim-lang/Nim/pull/19134"
},
{
"source": "cve@mitre.org",
"tags": [
"Third Party Advisory"
],
"url": "https://github.com/nim-lang/nimforum"
},
{
"source": "af854a3a-2127-422b-91ae-364da2661108",
"tags": [
"Issue Tracking",
"Vendor Advisory"
],
"url": "https://forum.nim-lang.org/t/8852"
},
{
"source": "af854a3a-2127-422b-91ae-364da2661108",
"tags": [
"Patch",
"Third Party Advisory"
],
"url": "https://github.com/nim-lang/Nim/commit/46275126b89218e64844eee169e8ced05dd0e2d7"
},
{
"source": "af854a3a-2127-422b-91ae-364da2661108",
"tags": [
"Third Party Advisory"
],
"url": "https://github.com/nim-lang/Nim/compare/v1.6.0...v1.6.2"
},
{
"source": "af854a3a-2127-422b-91ae-364da2661108",
"tags": [
"Patch",
"Third Party Advisory"
],
"url": "https://github.com/nim-lang/Nim/pull/19134"
},
{
"source": "af854a3a-2127-422b-91ae-364da2661108",
"tags": [
"Third Party Advisory"
],
"url": "https://github.com/nim-lang/nimforum"
}
],
"sourceIdentifier": "cve@mitre.org",
"vulnStatus": "Modified",
"weaknesses": [
{
"description": [
{
"lang": "en",
"value": "CWE-79"
}
],
"source": "nvd@nist.gov",
"type": "Primary"
},
{
"description": [
{
"lang": "en",
"value": "CWE-79"
}
],
"source": "134c704f-9b21-4f2e-91b3-4a467353bcc0",
"type": "Secondary"
}
]
}
},
"redhat_vex": {
"current_release_date": "2025-05-29T05:01:18+00:00",
"cve": "CVE-2021-46872",
"id": "CVE-2021-46872",
"initial_release_date": "2021-01-01T00:00:00+00:00",
"product_status:known_not_affected": "1",
"source": "Red Hat CSAF VEX",
"status": "final",
"title": "CVE-2021-46872",
"url": "https://security.access.redhat.com/data/csaf/v2/vex/2021/cve-2021-46872.json",
"version": "3"
},
"vulnrichment": {
"containers": {
"adp": [
{
"providerMetadata": {
"dateUpdated": "2024-08-04T05:17:42.923Z",
"orgId": "af854a3a-2127-422b-91ae-364da2661108",
"shortName": "CVE"
},
"references": [
{
"tags": [
"x_transferred"
],
"url": "https://github.com/nim-lang/nimforum"
},
{
"tags": [
"x_transferred"
],
"url": "https://forum.nim-lang.org/t/8852"
},
{
"tags": [
"x_transferred"
],
"url": "https://github.com/nim-lang/Nim/pull/19134"
},
{
"tags": [
"x_transferred"
],
"url": "https://github.com/nim-lang/Nim/compare/v1.6.0...v1.6.2"
},
{
"tags": [
"x_transferred"
],
"url": "https://github.com/nim-lang/Nim/commit/46275126b89218e64844eee169e8ced05dd0e2d7"
}
],
"title": "CVE Program Container"
},
{
"metrics": [
{
"cvssV3_1": {
"attackComplexity": "LOW",
"attackVector": "NETWORK",
"availabilityImpact": "NONE",
"baseScore": 6.1,
"baseSeverity": "MEDIUM",
"confidentialityImpact": "LOW",
"integrityImpact": "LOW",
"privilegesRequired": "NONE",
"scope": "CHANGED",
"userInteraction": "REQUIRED",
"vectorString": "CVSS:3.1/AV:N/AC:L/PR:N/UI:R/S:C/C:L/I:L/A:N",
"version": "3.1"
}
},
{
"other": {
"content": {
"id": "CVE-2021-46872",
"options": [
{
"Exploitation": "none"
},
{
"Automatable": "no"
},
{
"Technical Impact": "partial"
}
],
"role": "CISA Coordinator",
"timestamp": "2025-04-07T19:12:45.568123Z",
"version": "2.0.3"
},
"type": "ssvc"
}
}
],
"problemTypes": [
{
"descriptions": [
{
"cweId": "CWE-79",
"description": "CWE-79 Improper Neutralization of Input During Web Page Generation (\u0027Cross-site Scripting\u0027)",
"lang": "en",
"type": "CWE"
}
]
}
],
"providerMetadata": {
"dateUpdated": "2025-04-07T19:13:11.130Z",
"orgId": "134c704f-9b21-4f2e-91b3-4a467353bcc0",
"shortName": "CISA-ADP"
},
"title": "CISA ADP Vulnrichment"
}
],
"cna": {
"affected": [
{
"product": "n/a",
"vendor": "n/a",
"versions": [
{
"status": "affected",
"version": "n/a"
}
]
}
],
"descriptions": [
{
"lang": "en",
"value": "An issue was discovered in Nim before 1.6.2. The RST module of the Nim language stdlib, as used in NimForum and other products, permits the javascript: URI scheme and thus can lead to XSS in some applications. (Nim versions 1.6.2 and later are fixed; there may be backports of the fix to some earlier versions. NimForum 2.2.0 is fixed.)"
}
],
"problemTypes": [
{
"descriptions": [
{
"description": "n/a",
"lang": "en",
"type": "text"
}
]
}
],
"providerMetadata": {
"dateUpdated": "2023-01-13T00:00:00.000Z",
"orgId": "8254265b-2729-46b6-b9e3-3dfca2d5bfca",
"shortName": "mitre"
},
"references": [
{
"url": "https://github.com/nim-lang/nimforum"
},
{
"url": "https://forum.nim-lang.org/t/8852"
},
{
"url": "https://github.com/nim-lang/Nim/pull/19134"
},
{
"url": "https://github.com/nim-lang/Nim/compare/v1.6.0...v1.6.2"
},
{
"url": "https://github.com/nim-lang/Nim/commit/46275126b89218e64844eee169e8ced05dd0e2d7"
}
]
}
},
"cveMetadata": {
"assignerOrgId": "8254265b-2729-46b6-b9e3-3dfca2d5bfca",
"assignerShortName": "mitre",
"cveId": "CVE-2021-46872",
"datePublished": "2023-01-13T00:00:00.000Z",
"dateReserved": "2023-01-13T00:00:00.000Z",
"dateUpdated": "2025-04-07T19:13:15.282Z",
"state": "PUBLISHED"
},
"dataType": "CVE_RECORD",
"dataVersion": "5.1"
}
}
}
Loading…
Loading…
Drag nodes to arrange them. Double-click a related vulnerability to open it, or a source to visit its link. The Physics button on the left tunes the layout and the simulation; the legend at the bottom left hides or shows nodes by kind and by sighting type.
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.
Vulnerability timeline
Sightings and recorded dates, grouped by day · UTC
Loading timeline…
Loading…
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.