CVE-2026-106558 (GCVE-0-2026-106558)
Vulnerability from cvelistv5
Published
2026-10-07 14:45
Modified
2026-10-10 02:27
Severity ?
VLAI Severity ?
EPSS score ?
CWE
- CWE-502 - Deserialization of Untrusted Data
Summary
Backstage is an open framework for building developer portals. Prior to 1.14.8, 1.15.6, and 2.0.1, the @backstage/plugin-techdocs-node package improperly validated mapping-style markdown_extensions configuration. An authenticated attacker who can register or influence an SCM-backed documentation source may bypass TechDocs sanitization and cause Python objects to be imported and instantiated in the generator runtime, leading to arbitrary code execution. Earlier fixes in versions 1.14.6 and 1.15.4 did not fully address the supported mapping representation of markdown_extensions. Impact is greatest when documentation generation runs with backend credentials, filesystem access, or internal network access. This issue is fixed in versions 1.14.8, 1.15.6, and 2.0.1.
References
| URL | Tags | |
|---|---|---|
|
|
||
Impacted products
| Vendor | Product | Version | |||||||
|---|---|---|---|---|---|---|---|---|---|
| backstage | backstage |
Version: < 1.50.7 Version: >= 1.51.0-next.0, < 1.54.9 Version: >= 1.55.0-next.0, < 1.55.2 |
|||||||
|
|||||||||
{
"containers": {
"adp": [
{
"metrics": [
{
"other": {
"content": {
"id": "CVE-2026-106558",
"options": [
{
"Exploitation": "none"
},
{
"Automatable": "no"
},
{
"Technical Impact": "total"
}
],
"role": "CISA Coordinator",
"timestamp": "2026-10-10T02:27:02.807453Z",
"version": "2.0.3"
},
"type": "ssvc"
}
}
],
"providerMetadata": {
"dateUpdated": "2026-10-10T02:27:17.131Z",
"orgId": "134c704f-9b21-4f2e-91b3-4a467353bcc0",
"shortName": "CISA-ADP"
},
"title": "CISA ADP Vulnrichment"
}
],
"cna": {
"affected": [
{
"product": "backstage",
"vendor": "backstage",
"versions": [
{
"status": "affected",
"version": "\u003c 1.50.7"
},
{
"status": "affected",
"version": "\u003e= 1.51.0-next.0, \u003c 1.54.9"
},
{
"status": "affected",
"version": "\u003e= 1.55.0-next.0, \u003c 1.55.2"
}
]
},
{
"product": "plugin-techdocs-node",
"vendor": "@backstage",
"versions": [
{
"status": "affected",
"version": "\u003c 1.14.8"
},
{
"status": "affected",
"version": "\u003e= 1.15.0, \u003c 1.15.6"
},
{
"status": "affected",
"version": "\u003e= 2.0.0, \u003c 2.0.1"
}
]
}
],
"descriptions": [
{
"lang": "en",
"value": "Backstage is an open framework for building developer portals. Prior to 1.14.8, 1.15.6, and 2.0.1, the @backstage/plugin-techdocs-node package improperly validated mapping-style markdown_extensions configuration. An authenticated attacker who can register or influence an SCM-backed documentation source may bypass TechDocs sanitization and cause Python objects to be imported and instantiated in the generator runtime, leading to arbitrary code execution. Earlier fixes in versions 1.14.6 and 1.15.4 did not fully address the supported mapping representation of markdown_extensions. Impact is greatest when documentation generation runs with backend credentials, filesystem access, or internal network access. This issue is fixed in versions 1.14.8, 1.15.6, and 2.0.1."
}
],
"metrics": [
{
"cvssV3_1": {
"attackComplexity": "LOW",
"attackVector": "NETWORK",
"availabilityImpact": "HIGH",
"baseScore": 8.8,
"baseSeverity": "HIGH",
"confidentialityImpact": "HIGH",
"integrityImpact": "HIGH",
"privilegesRequired": "LOW",
"scope": "UNCHANGED",
"userInteraction": "NONE",
"vectorString": "CVSS:3.1/AV:N/AC:L/PR:L/UI:N/S:U/C:H/I:H/A:H",
"version": "3.1"
}
}
],
"problemTypes": [
{
"descriptions": [
{
"cweId": "CWE-502",
"description": "CWE-502: Deserialization of Untrusted Data",
"lang": "en",
"type": "CWE"
}
]
}
],
"providerMetadata": {
"dateUpdated": "2026-10-07T14:45:25.679Z",
"orgId": "a0819718-46f1-4df5-94e2-005712e83aaa",
"shortName": "GitHub_M"
},
"references": [
{
"name": "https://github.com/backstage/backstage/security/advisories/GHSA-qmw3-745m-w99g",
"tags": [
"x_refsource_CONFIRM"
],
"url": "https://github.com/backstage/backstage/security/advisories/GHSA-qmw3-745m-w99g"
},
{
"name": "https://github.com/backstage/backstage/commit/32723a0fe4e12ed80535fc65d5331765c55aa91b",
"tags": [
"x_refsource_MISC"
],
"url": "https://github.com/backstage/backstage/commit/32723a0fe4e12ed80535fc65d5331765c55aa91b"
},
{
"name": "https://github.com/backstage/backstage/commit/944edb51c8524d3664b18f2d57ba101b1c93b709",
"tags": [
"x_refsource_MISC"
],
"url": "https://github.com/backstage/backstage/commit/944edb51c8524d3664b18f2d57ba101b1c93b709"
},
{
"name": "https://github.com/backstage/backstage/commit/f18e9abcc6051491862b15e4fc60e69f8d52310c",
"tags": [
"x_refsource_MISC"
],
"url": "https://github.com/backstage/backstage/commit/f18e9abcc6051491862b15e4fc60e69f8d52310c"
},
{
"name": "https://github.com/backstage/backstage/releases/tag/v1.50.7",
"tags": [
"x_refsource_MISC"
],
"url": "https://github.com/backstage/backstage/releases/tag/v1.50.7"
},
{
"name": "https://github.com/backstage/backstage/releases/tag/v1.54.9",
"tags": [
"x_refsource_MISC"
],
"url": "https://github.com/backstage/backstage/releases/tag/v1.54.9"
},
{
"name": "https://github.com/backstage/backstage/releases/tag/v1.55.2",
"tags": [
"x_refsource_MISC"
],
"url": "https://github.com/backstage/backstage/releases/tag/v1.55.2"
}
],
"source": {
"advisory": "GHSA-qmw3-745m-w99g",
"discovery": "UNKNOWN"
},
"title": "Backstage: Improper validation of TechDocs MkDocs configuration"
}
},
"cveMetadata": {
"assignerOrgId": "a0819718-46f1-4df5-94e2-005712e83aaa",
"assignerShortName": "GitHub_M",
"cveId": "CVE-2026-106558",
"datePublished": "2026-10-07T14:45:25.679Z",
"dateReserved": "2026-10-06T20:31:59.017Z",
"dateUpdated": "2026-10-10T02:27:17.131Z",
"state": "PUBLISHED"
},
"dataType": "CVE_RECORD",
"dataVersion": "5.2",
"vulnerability-lookup:meta": {
"vulnrichment": {
"containers": "{\"adp\": [{\"title\": \"CISA ADP Vulnrichment\", \"metrics\": [{\"other\": {\"type\": \"ssvc\", \"content\": {\"id\": \"CVE-2026-106558\", \"role\": \"CISA Coordinator\", \"options\": [{\"Exploitation\": \"none\"}, {\"Automatable\": \"no\"}, {\"Technical Impact\": \"total\"}], \"version\": \"2.0.3\", \"timestamp\": \"2026-10-10T02:27:02.807453Z\"}}}], \"providerMetadata\": {\"orgId\": \"134c704f-9b21-4f2e-91b3-4a467353bcc0\", \"shortName\": \"CISA-ADP\", \"dateUpdated\": \"2026-10-10T02:27:11.696Z\"}}], \"cna\": {\"title\": \"Backstage: Improper validation of TechDocs MkDocs configuration\", \"source\": {\"advisory\": \"GHSA-qmw3-745m-w99g\", \"discovery\": \"UNKNOWN\"}, \"metrics\": [{\"cvssV3_1\": {\"scope\": \"UNCHANGED\", \"version\": \"3.1\", \"baseScore\": 8.8, \"attackVector\": \"NETWORK\", \"baseSeverity\": \"HIGH\", \"vectorString\": \"CVSS:3.1/AV:N/AC:L/PR:L/UI:N/S:U/C:H/I:H/A:H\", \"integrityImpact\": \"HIGH\", \"userInteraction\": \"NONE\", \"attackComplexity\": \"LOW\", \"availabilityImpact\": \"HIGH\", \"privilegesRequired\": \"LOW\", \"confidentialityImpact\": \"HIGH\"}}], \"affected\": [{\"vendor\": \"backstage\", \"product\": \"backstage\", \"versions\": [{\"status\": \"affected\", \"version\": \"\u003c 1.50.7\"}, {\"status\": \"affected\", \"version\": \"\u003e= 1.51.0-next.0, \u003c 1.54.9\"}, {\"status\": \"affected\", \"version\": \"\u003e= 1.55.0-next.0, \u003c 1.55.2\"}]}, {\"vendor\": \"@backstage\", \"product\": \"plugin-techdocs-node\", \"versions\": [{\"status\": \"affected\", \"version\": \"\u003c 1.14.8\"}, {\"status\": \"affected\", \"version\": \"\u003e= 1.15.0, \u003c 1.15.6\"}, {\"status\": \"affected\", \"version\": \"\u003e= 2.0.0, \u003c 2.0.1\"}]}], \"references\": [{\"url\": \"https://github.com/backstage/backstage/security/advisories/GHSA-qmw3-745m-w99g\", \"name\": \"https://github.com/backstage/backstage/security/advisories/GHSA-qmw3-745m-w99g\", \"tags\": [\"x_refsource_CONFIRM\"]}, {\"url\": \"https://github.com/backstage/backstage/commit/32723a0fe4e12ed80535fc65d5331765c55aa91b\", \"name\": \"https://github.com/backstage/backstage/commit/32723a0fe4e12ed80535fc65d5331765c55aa91b\", \"tags\": [\"x_refsource_MISC\"]}, {\"url\": \"https://github.com/backstage/backstage/commit/944edb51c8524d3664b18f2d57ba101b1c93b709\", \"name\": \"https://github.com/backstage/backstage/commit/944edb51c8524d3664b18f2d57ba101b1c93b709\", \"tags\": [\"x_refsource_MISC\"]}, {\"url\": \"https://github.com/backstage/backstage/commit/f18e9abcc6051491862b15e4fc60e69f8d52310c\", \"name\": \"https://github.com/backstage/backstage/commit/f18e9abcc6051491862b15e4fc60e69f8d52310c\", \"tags\": [\"x_refsource_MISC\"]}, {\"url\": \"https://github.com/backstage/backstage/releases/tag/v1.50.7\", \"name\": \"https://github.com/backstage/backstage/releases/tag/v1.50.7\", \"tags\": [\"x_refsource_MISC\"]}, {\"url\": \"https://github.com/backstage/backstage/releases/tag/v1.54.9\", \"name\": \"https://github.com/backstage/backstage/releases/tag/v1.54.9\", \"tags\": [\"x_refsource_MISC\"]}, {\"url\": \"https://github.com/backstage/backstage/releases/tag/v1.55.2\", \"name\": \"https://github.com/backstage/backstage/releases/tag/v1.55.2\", \"tags\": [\"x_refsource_MISC\"]}], \"descriptions\": [{\"lang\": \"en\", \"value\": \"Backstage is an open framework for building developer portals. Prior to 1.14.8, 1.15.6, and 2.0.1, the @backstage/plugin-techdocs-node package improperly validated mapping-style markdown_extensions configuration. An authenticated attacker who can register or influence an SCM-backed documentation source may bypass TechDocs sanitization and cause Python objects to be imported and instantiated in the generator runtime, leading to arbitrary code execution. Earlier fixes in versions 1.14.6 and 1.15.4 did not fully address the supported mapping representation of markdown_extensions. Impact is greatest when documentation generation runs with backend credentials, filesystem access, or internal network access. This issue is fixed in versions 1.14.8, 1.15.6, and 2.0.1.\"}], \"problemTypes\": [{\"descriptions\": [{\"lang\": \"en\", \"type\": \"CWE\", \"cweId\": \"CWE-502\", \"description\": \"CWE-502: Deserialization of Untrusted Data\"}]}], \"providerMetadata\": {\"orgId\": \"a0819718-46f1-4df5-94e2-005712e83aaa\", \"shortName\": \"GitHub_M\", \"dateUpdated\": \"2026-10-07T14:45:25.679Z\"}}}",
"cveMetadata": "{\"cveId\": \"CVE-2026-106558\", \"state\": \"PUBLISHED\", \"dateUpdated\": \"2026-10-10T02:27:17.131Z\", \"dateReserved\": \"2026-10-06T20:31:59.017Z\", \"assignerOrgId\": \"a0819718-46f1-4df5-94e2-005712e83aaa\", \"datePublished\": \"2026-10-07T14:45:25.679Z\", \"assignerShortName\": \"GitHub_M\"}",
"dataType": "CVE_RECORD",
"dataVersion": "5.2"
}
}
}
Loading…
Loading…
Sightings
| Author | Source | Type | Date |
|---|
Nomenclature
- Seen: The vulnerability was mentioned, discussed, or seen somewhere by the user.
- Confirmed: The vulnerability is confirmed from an analyst perspective.
- Published Proof of Concept: A public proof of concept is available for this vulnerability.
- Exploited: This vulnerability was exploited and seen by the user reporting the sighting.
- Patched: This vulnerability was successfully patched by the user reporting the sighting.
- Not exploited: This vulnerability was not exploited or seen by the user reporting the sighting.
- Not confirmed: The user expresses doubt about the veracity of the vulnerability.
- Not patched: This vulnerability was not successfully patched by the user reporting the sighting.
Loading…
Loading…