CVE-2026-7888 (GCVE-0-2026-7888)
Vulnerability from cvelistv5 – Published: 2026-06-03 18:10 – Updated: 2026-09-11 19:04
VLAI
EPSS
VEX
Title
Concrete CMS below 9.5.3 is vulnerable to PHP Object Injection via unserialize() calls in the Workflow, Form block, and File/Set components that lack the allowed_classes restriction.
Summary
Concrete CMS below 9.5.3 is vulnerable to PHP Object Injection via unserialize()
calls in the Workflow, Form block, and File/Set components that lack the
allowed_classes restriction. The Form block and File/Set sinks were addressed in
9.5.2; the Workflow component sinks were addressed in 9.5.3. An unauthenticated
attacker may trigger arbitrary PHP object instantiation if a malicious serialized
payload has been placed in the database. Thanks XananasX7 and Sanjorn Keeratirungsan
(dizconnect) for independently reporting the original components, and sh4d0byss for
reporting the Workflow component wasn't fixed in 9.5.2. The Concrete CMS security team gave this
vulnerability a CVSS v.4.0 score of 8.4 with vector CVSS:4.0/AV:L/AC:L/AT:N/PR:H/UI:N/
VC:H/VI:H/VA:H/SC:N/SI:N/SA:N.
Severity
SSVC
Exploitation: none
Automatable: no
Technical Impact: total
CISA Coordinator · CISA-ADP (v2.0.3)
Decision recorded 2026-06-03 19:07 UTC
CWE
- CWE-502 - Deserialization of untrusted data
Assigner
References
1 reference
| URL | Tags |
|---|---|
| https://documentation.concretecms.org/9-x/develop… | release-notes |
Impacted products
1 product
| Vendor | Product | Version | CPE status | |
|---|---|---|---|---|
| Concrete CMS | Concrete CMS |
Affected:
5.0 , ≤ 9.5.2
(git)
|
guessed |
{
"containers": {
"adp": [
{
"metrics": [
{
"other": {
"content": {
"id": "CVE-2026-7888",
"options": [
{
"Exploitation": "none"
},
{
"Automatable": "no"
},
{
"Technical Impact": "total"
}
],
"role": "CISA Coordinator",
"timestamp": "2026-06-03T19:07:44.886735Z",
"version": "2.0.3"
},
"type": "ssvc"
}
}
],
"providerMetadata": {
"dateUpdated": "2026-06-03T19:07:56.723Z",
"orgId": "134c704f-9b21-4f2e-91b3-4a467353bcc0",
"shortName": "CISA-ADP"
},
"title": "CISA ADP Vulnrichment"
}
],
"cna": {
"affected": [
{
"collectionURL": "https://github.com/concretecms/concretecms",
"defaultStatus": "unaffected",
"product": "Concrete CMS",
"repo": "https://github.com/concretecms/concretecms",
"vendor": "Concrete CMS",
"versions": [
{
"lessThanOrEqual": "9.5.2",
"status": "affected",
"version": "5.0",
"versionType": "git"
}
]
}
],
"credits": [
{
"lang": "en",
"type": "remediation developer",
"value": "XananasX7"
},
{
"lang": "en",
"type": "finder",
"value": "Sanjorn Keeratirungsan (dizconnect)"
},
{
"lang": "en",
"type": "finder",
"value": "sh4d0byss"
}
],
"descriptions": [
{
"lang": "en",
"supportingMedia": [
{
"base64": false,
"type": "text/html",
"value": "Concrete CMS below 9.5.3 is vulnerable to PHP Object Injection via unserialize()\u003cbr\u003ecalls in the Workflow, Form block, and File/Set components that lack the\u003cbr\u003eallowed_classes restriction. The Form block and File/Set sinks were addressed in\u003cbr\u003e9.5.2; the Workflow component sinks were addressed in 9.5.3. An unauthenticated\u003cbr\u003eattacker may trigger arbitrary PHP object instantiation if a malicious serialized\u003cbr\u003epayload has been placed in the database. Thanks XananasX7 and Sanjorn Keeratirungsan\u003cbr\u003e(dizconnect) for independently reporting the original components, and sh4d0byss for\u003cbr\u003ereporting the Workflow component wasn\u0027t fixed in 9.5.2. The Concrete CMS security team gave this\u003cbr\u003evulnerability a CVSS v.4.0 score of 8.4 with vector CVSS:4.0/AV:L/AC:L/AT:N/PR:H/UI:N/\u003cbr\u003eVC:H/VI:H/VA:H/SC:N/SI:N/SA:N."
}
],
"value": "Concrete CMS below 9.5.3 is vulnerable to PHP Object Injection via unserialize()\ncalls in the Workflow, Form block, and File/Set components that lack the\nallowed_classes restriction. The Form block and File/Set sinks were addressed in\n9.5.2; the Workflow component sinks were addressed in 9.5.3. An unauthenticated\nattacker may trigger arbitrary PHP object instantiation if a malicious serialized\npayload has been placed in the database. Thanks XananasX7 and Sanjorn Keeratirungsan\n(dizconnect) for independently reporting the original components, and sh4d0byss for\nreporting the Workflow component wasn\u0027t fixed in 9.5.2. The Concrete CMS security team gave this\nvulnerability a CVSS v.4.0 score of 8.4 with vector CVSS:4.0/AV:L/AC:L/AT:N/PR:H/UI:N/\nVC:H/VI:H/VA:H/SC:N/SI:N/SA:N."
}
],
"impacts": [
{
"capecId": "CAPEC-586",
"descriptions": [
{
"lang": "en",
"value": "CAPEC-586 Object Injection"
}
]
}
],
"metrics": [
{
"cvssV4_0": {
"Automatable": "NOT_DEFINED",
"Recovery": "NOT_DEFINED",
"Safety": "NOT_DEFINED",
"attackComplexity": "LOW",
"attackRequirements": "NONE",
"attackVector": "LOCAL",
"baseScore": 8.4,
"baseSeverity": "HIGH",
"exploitMaturity": "NOT_DEFINED",
"privilegesRequired": "HIGH",
"providerUrgency": "NOT_DEFINED",
"subAvailabilityImpact": "NONE",
"subConfidentialityImpact": "NONE",
"subIntegrityImpact": "NONE",
"userInteraction": "NONE",
"valueDensity": "NOT_DEFINED",
"vectorString": "CVSS:4.0/AV:L/AC:L/AT:N/PR:H/UI:N/VC:H/VI:H/VA:H/SC:N/SI:N/SA:N",
"version": "4.0",
"vulnAvailabilityImpact": "HIGH",
"vulnConfidentialityImpact": "HIGH",
"vulnIntegrityImpact": "HIGH",
"vulnerabilityResponseEffort": "NOT_DEFINED"
},
"format": "CVSS",
"scenarios": [
{
"lang": "en",
"value": "GENERAL"
}
]
}
],
"problemTypes": [
{
"descriptions": [
{
"cweId": "CWE-502",
"description": "CWE-502 Deserialization of untrusted data",
"lang": "en",
"type": "CWE"
}
]
}
],
"providerMetadata": {
"dateUpdated": "2026-09-11T19:04:23.786Z",
"orgId": "ff5b8ace-8b95-4078-9743-eac1ca5451de",
"shortName": "ConcreteCMS"
},
"references": [
{
"tags": [
"release-notes"
],
"url": "https://documentation.concretecms.org/9-x/developers/introduction/version-history/952-release-notes"
}
],
"source": {
"advisory": "https://hackerone.com/reports/3756743",
"defect": [
"HackerOne"
],
"discovery": "EXTERNAL"
},
"title": "Concrete CMS below 9.5.3 is vulnerable to PHP Object Injection via unserialize() calls in the Workflow, Form block, and File/Set components that lack the allowed_classes restriction.",
"x_generator": {
"engine": "Vulnogram 1.0.2"
}
}
},
"cveMetadata": {
"assignerOrgId": "ff5b8ace-8b95-4078-9743-eac1ca5451de",
"assignerShortName": "ConcreteCMS",
"cveId": "CVE-2026-7888",
"datePublished": "2026-06-03T18:10:10.917Z",
"dateReserved": "2026-05-05T20:23:08.863Z",
"dateUpdated": "2026-09-11T19:04:23.786Z",
"state": "PUBLISHED"
},
"dataType": "CVE_RECORD",
"dataVersion": "5.2",
"vulnerability-lookup:meta": {
"epss": {
"cve": "CVE-2026-7888",
"date": "2026-09-16",
"epss": "0.00155",
"percentile": "0.05063"
},
"nvd": "{\"cve\":{\"id\":\"CVE-2026-7888\",\"sourceIdentifier\":\"ff5b8ace-8b95-4078-9743-eac1ca5451de\",\"published\":\"2026-06-03T19:16:38.910\",\"lastModified\":\"2026-09-11T20:18:54.320\",\"vulnStatus\":\"Deferred\",\"cveTags\":[],\"descriptions\":[{\"lang\":\"en\",\"value\":\"Concrete CMS below 9.5.3 is vulnerable to PHP Object Injection via unserialize()\\ncalls in the Workflow, Form block, and File/Set components that lack the\\nallowed_classes restriction. The Form block and File/Set sinks were addressed in\\n9.5.2; the Workflow component sinks were addressed in 9.5.3. An unauthenticated\\nattacker may trigger arbitrary PHP object instantiation if a malicious serialized\\npayload has been placed in the database. Thanks XananasX7 and Sanjorn Keeratirungsan\\n(dizconnect) for independently reporting the original components, and sh4d0byss for\\nreporting the Workflow component wasn\u0027t fixed in 9.5.2. The Concrete CMS security team gave this\\nvulnerability a CVSS v.4.0 score of 8.4 with vector CVSS:4.0/AV:L/AC:L/AT:N/PR:H/UI:N/\\nVC:H/VI:H/VA:H/SC:N/SI:N/SA:N.\"},{\"lang\":\"es\",\"value\":\"Concrete CMS anterior a 9.5.2 es vulnerable a la Inyecci\u00f3n de objetos PHP a trav\u00e9s de llamadas a unserialize() en los componentes Workflow, Form block y File/Set que carecen de la restricci\u00f3n allowed_classes. Un atacante no autenticado puede desencadenar la instanciaci\u00f3n arbitraria de objetos PHP si se ha colocado una carga \u00fatil serializada maliciosa en la base de datos. Gracias a XananasX7 y Sanjorn Keeratirungsan (dizconnect) por informar ambos de forma independiente. El equipo de seguridad de Concrete CMS otorg\u00f3 a esta vulnerabilidad una puntuaci\u00f3n CVSS v.4.0 de 8.4 con el vector CVSS:4.0/AV:L/AC:L/AT:N/PR:H/UI:N/VC:H/VI:H/VA:H/SC:N/SI:N/SA:N.\"}],\"affected\":[{\"source\":\"ff5b8ace-8b95-4078-9743-eac1ca5451de\",\"affectedData\":[{\"vendor\":\"Concrete CMS\",\"product\":\"Concrete CMS\",\"defaultStatus\":\"unaffected\",\"collectionURL\":\"https://github.com/concretecms/concretecms\",\"repo\":\"https://github.com/concretecms/concretecms\",\"versions\":[{\"version\":\"5.0\",\"lessThanOrEqual\":\"9.5.2\",\"versionType\":\"git\",\"status\":\"affected\"}]}]}],\"metrics\":{\"cvssMetricV40\":[{\"source\":\"ff5b8ace-8b95-4078-9743-eac1ca5451de\",\"type\":\"Secondary\",\"cvssData\":{\"version\":\"4.0\",\"vectorString\":\"CVSS:4.0/AV:L/AC:L/AT:N/PR:H/UI:N/VC:H/VI:H/VA:H/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\",\"baseScore\":8.4,\"baseSeverity\":\"HIGH\",\"attackVector\":\"LOCAL\",\"attackComplexity\":\"LOW\",\"attackRequirements\":\"NONE\",\"privilegesRequired\":\"HIGH\",\"userInteraction\":\"NONE\",\"vulnConfidentialityImpact\":\"HIGH\",\"vulnIntegrityImpact\":\"HIGH\",\"vulnAvailabilityImpact\":\"HIGH\",\"subConfidentialityImpact\":\"NONE\",\"subIntegrityImpact\":\"NONE\",\"subAvailabilityImpact\":\"NONE\",\"exploitMaturity\":\"NOT_DEFINED\",\"confidentialityRequirement\":\"NOT_DEFINED\",\"integrityRequirement\":\"NOT_DEFINED\",\"availabilityRequirement\":\"NOT_DEFINED\",\"modifiedAttackVector\":\"NOT_DEFINED\",\"modifiedAttackComplexity\":\"NOT_DEFINED\",\"modifiedAttackRequirements\":\"NOT_DEFINED\",\"modifiedPrivilegesRequired\":\"NOT_DEFINED\",\"modifiedUserInteraction\":\"NOT_DEFINED\",\"modifiedVulnConfidentialityImpact\":\"NOT_DEFINED\",\"modifiedVulnIntegrityImpact\":\"NOT_DEFINED\",\"modifiedVulnAvailabilityImpact\":\"NOT_DEFINED\",\"modifiedSubConfidentialityImpact\":\"NOT_DEFINED\",\"modifiedSubIntegrityImpact\":\"NOT_DEFINED\",\"modifiedSubAvailabilityImpact\":\"NOT_DEFINED\",\"Safety\":\"NOT_DEFINED\",\"Automatable\":\"NOT_DEFINED\",\"Recovery\":\"NOT_DEFINED\",\"valueDensity\":\"NOT_DEFINED\",\"vulnerabilityResponseEffort\":\"NOT_DEFINED\",\"providerUrgency\":\"NOT_DEFINED\"}}],\"ssvcV203\":[{\"source\":\"134c704f-9b21-4f2e-91b3-4a467353bcc0\",\"ssvcData\":{\"timestamp\":\"2026-06-03T19:07:44.886735Z\",\"id\":\"CVE-2026-7888\",\"options\":[{\"exploitation\":\"none\"},{\"automatable\":\"no\"},{\"technicalImpact\":\"total\"}],\"role\":\"CISA Coordinator\",\"version\":\"2.0.3\"}}]},\"weaknesses\":[{\"source\":\"ff5b8ace-8b95-4078-9743-eac1ca5451de\",\"type\":\"Secondary\",\"description\":[{\"lang\":\"en\",\"value\":\"CWE-502\"}]}],\"references\":[{\"url\":\"https://documentation.concretecms.org/9-x/developers/introduction/version-history/952-release-notes\",\"source\":\"ff5b8ace-8b95-4078-9743-eac1ca5451de\"}]}}",
"redhat_vex": {
"current_release_date": "2026-06-05T19:22:33+00:00",
"cve": "CVE-2026-7888",
"id": "CVE-2026-7888",
"initial_release_date": "2026-01-01T00:00:00+00:00",
"product_status:known_not_affected": "1",
"source": "Red Hat CSAF VEX",
"status": "final",
"title": "Concrete CMS below 9.5.2 is vulnerable to PHP Object Injection via unserialize() calls in the Workflow, Form block, and File/Set components that lack the allowed_classes restriction.",
"url": "https://security.access.redhat.com/data/csaf/v2/vex/2026/cve-2026-7888.json",
"version": "3"
},
"vulnrichment": {
"containers": "{\"adp\": [{\"title\": \"CISA ADP Vulnrichment\", \"metrics\": [{\"other\": {\"type\": \"ssvc\", \"content\": {\"id\": \"CVE-2026-7888\", \"role\": \"CISA Coordinator\", \"options\": [{\"Exploitation\": \"none\"}, {\"Automatable\": \"no\"}, {\"Technical Impact\": \"total\"}], \"version\": \"2.0.3\", \"timestamp\": \"2026-06-03T19:07:44.886735Z\"}}}], \"providerMetadata\": {\"orgId\": \"134c704f-9b21-4f2e-91b3-4a467353bcc0\", \"shortName\": \"CISA-ADP\", \"dateUpdated\": \"2026-06-03T19:07:52.022Z\"}}], \"cna\": {\"title\": \"Concrete CMS below 9.5.3 is vulnerable to PHP Object Injection via unserialize() calls in the Workflow, Form block, and File/Set components that lack the allowed_classes restriction.\", \"source\": {\"defect\": [\"HackerOne\"], \"advisory\": \"https://hackerone.com/reports/3756743\", \"discovery\": \"EXTERNAL\"}, \"credits\": [{\"lang\": \"en\", \"type\": \"remediation developer\", \"value\": \"XananasX7\"}, {\"lang\": \"en\", \"type\": \"finder\", \"value\": \"Sanjorn Keeratirungsan (dizconnect)\"}, {\"lang\": \"en\", \"type\": \"finder\", \"value\": \"sh4d0byss\"}], \"impacts\": [{\"capecId\": \"CAPEC-586\", \"descriptions\": [{\"lang\": \"en\", \"value\": \"CAPEC-586 Object Injection\"}]}], \"metrics\": [{\"format\": \"CVSS\", \"cvssV4_0\": {\"Safety\": \"NOT_DEFINED\", \"version\": \"4.0\", \"Recovery\": \"NOT_DEFINED\", \"baseScore\": 8.4, \"Automatable\": \"NOT_DEFINED\", \"attackVector\": \"LOCAL\", \"baseSeverity\": \"HIGH\", \"valueDensity\": \"NOT_DEFINED\", \"vectorString\": \"CVSS:4.0/AV:L/AC:L/AT:N/PR:H/UI:N/VC:H/VI:H/VA:H/SC:N/SI:N/SA:N\", \"exploitMaturity\": \"NOT_DEFINED\", \"providerUrgency\": \"NOT_DEFINED\", \"userInteraction\": \"NONE\", \"attackComplexity\": \"LOW\", \"attackRequirements\": \"NONE\", \"privilegesRequired\": \"HIGH\", \"subIntegrityImpact\": \"NONE\", \"vulnIntegrityImpact\": \"HIGH\", \"subAvailabilityImpact\": \"NONE\", \"vulnAvailabilityImpact\": \"HIGH\", \"subConfidentialityImpact\": \"NONE\", \"vulnConfidentialityImpact\": \"HIGH\", \"vulnerabilityResponseEffort\": \"NOT_DEFINED\"}, \"scenarios\": [{\"lang\": \"en\", \"value\": \"GENERAL\"}]}], \"affected\": [{\"repo\": \"https://github.com/concretecms/concretecms\", \"vendor\": \"Concrete CMS\", \"product\": \"Concrete CMS\", \"versions\": [{\"status\": \"affected\", \"version\": \"5.0\", \"versionType\": \"git\", \"lessThanOrEqual\": \"9.5.2\"}], \"collectionURL\": \"https://github.com/concretecms/concretecms\", \"defaultStatus\": \"unaffected\"}], \"references\": [{\"url\": \"https://documentation.concretecms.org/9-x/developers/introduction/version-history/952-release-notes\", \"tags\": [\"release-notes\"]}], \"x_generator\": {\"engine\": \"Vulnogram 1.0.2\"}, \"descriptions\": [{\"lang\": \"en\", \"value\": \"Concrete CMS below 9.5.3 is vulnerable to PHP Object Injection via unserialize()\\ncalls in the Workflow, Form block, and File/Set components that lack the\\nallowed_classes restriction. The Form block and File/Set sinks were addressed in\\n9.5.2; the Workflow component sinks were addressed in 9.5.3. An unauthenticated\\nattacker may trigger arbitrary PHP object instantiation if a malicious serialized\\npayload has been placed in the database. Thanks XananasX7 and Sanjorn Keeratirungsan\\n(dizconnect) for independently reporting the original components, and sh4d0byss for\\nreporting the Workflow component wasn\u0027t fixed in 9.5.2. The Concrete CMS security team gave this\\nvulnerability a CVSS v.4.0 score of 8.4 with vector CVSS:4.0/AV:L/AC:L/AT:N/PR:H/UI:N/\\nVC:H/VI:H/VA:H/SC:N/SI:N/SA:N.\", \"supportingMedia\": [{\"type\": \"text/html\", \"value\": \"Concrete CMS below 9.5.3 is vulnerable to PHP Object Injection via unserialize()\u003cbr\u003ecalls in the Workflow, Form block, and File/Set components that lack the\u003cbr\u003eallowed_classes restriction. The Form block and File/Set sinks were addressed in\u003cbr\u003e9.5.2; the Workflow component sinks were addressed in 9.5.3. An unauthenticated\u003cbr\u003eattacker may trigger arbitrary PHP object instantiation if a malicious serialized\u003cbr\u003epayload has been placed in the database. Thanks XananasX7 and Sanjorn Keeratirungsan\u003cbr\u003e(dizconnect) for independently reporting the original components, and sh4d0byss for\u003cbr\u003ereporting the Workflow component wasn\u0027t fixed in 9.5.2. The Concrete CMS security team gave this\u003cbr\u003evulnerability a CVSS v.4.0 score of 8.4 with vector CVSS:4.0/AV:L/AC:L/AT:N/PR:H/UI:N/\u003cbr\u003eVC:H/VI:H/VA:H/SC:N/SI:N/SA:N.\", \"base64\": false}]}], \"problemTypes\": [{\"descriptions\": [{\"lang\": \"en\", \"type\": \"CWE\", \"cweId\": \"CWE-502\", \"description\": \"CWE-502 Deserialization of untrusted data\"}]}], \"providerMetadata\": {\"orgId\": \"ff5b8ace-8b95-4078-9743-eac1ca5451de\", \"shortName\": \"ConcreteCMS\", \"dateUpdated\": \"2026-09-11T19:04:23.786Z\"}}}",
"cveMetadata": "{\"cveId\": \"CVE-2026-7888\", \"state\": \"PUBLISHED\", \"dateUpdated\": \"2026-09-11T19:04:23.786Z\", \"dateReserved\": \"2026-05-05T20:23:08.863Z\", \"assignerOrgId\": \"ff5b8ace-8b95-4078-9743-eac1ca5451de\", \"datePublished\": \"2026-06-03T18:10:10.917Z\", \"assignerShortName\": \"ConcreteCMS\"}",
"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…