CVE-2026-45119 (GCVE-0-2026-45119)
Vulnerability from cvelistv5 – Published: 2026-08-18 15:49 – Updated: 2026-08-19 14:41
VLAI
EPSS
VEX
Title
MyBB: ACP UTF-8 Conversion CSRF
Summary
MyBB is free and open source forum software. Prior to 1.8.40, the Admin CP UTF-8 Conversion module does not validate certain requests correctly, allowing same-site attackers to alter table encoding and deny service with a specially crafted URL. The do=all control flow in admin/modules/tools/system_health.php performs ALTER TABLE operations, column rewrite phases, and fulltext index rebuilds on GET requests for the database table named by the table parameter without request verification. The uniquely identifying implementation details include GET requests without request verification. This issue is fixed in version 1.8.40.
Severity
4.6 (Medium)
SSVC
Exploitation: none
Automatable: no
Technical Impact: partial
CISA Coordinator · CISA-ADP (v2.0.3)
Decision recorded 2026-08-19 14:40 UTC
CWE
- CWE-352 - Cross-Site Request Forgery (CSRF)
Assigner
References
4 references
| URL | Tags |
|---|---|
| https://github.com/mybb/mybb/security/advisories/… | x_refsource_CONFIRM |
| https://github.com/mybb/mybb/commit/70d445d14c835… | x_refsource_MISC |
| https://github.com/mybb/mybb/releases/tag/mybb_1840 | x_refsource_MISC |
| https://mybb.com/versions/1.8.40 | x_refsource_MISC |
{
"containers": {
"adp": [
{
"metrics": [
{
"other": {
"content": {
"id": "CVE-2026-45119",
"options": [
{
"Exploitation": "none"
},
{
"Automatable": "no"
},
{
"Technical Impact": "partial"
}
],
"role": "CISA Coordinator",
"timestamp": "2026-08-19T14:40:56.896930Z",
"version": "2.0.3"
},
"type": "ssvc"
}
}
],
"providerMetadata": {
"dateUpdated": "2026-08-19T14:41:09.985Z",
"orgId": "134c704f-9b21-4f2e-91b3-4a467353bcc0",
"shortName": "CISA-ADP"
},
"title": "CISA ADP Vulnrichment"
}
],
"cna": {
"affected": [
{
"product": "mybb",
"vendor": "mybb",
"versions": [
{
"status": "affected",
"version": "\u003c 1.8.40"
}
]
}
],
"descriptions": [
{
"lang": "en",
"value": "MyBB is free and open source forum software. Prior to 1.8.40, the Admin CP UTF-8 Conversion module does not validate certain requests correctly, allowing same-site attackers to alter table encoding and deny service with a specially crafted URL. The do=all control flow in admin/modules/tools/system_health.php performs ALTER TABLE operations, column rewrite phases, and fulltext index rebuilds on GET requests for the database table named by the table parameter without request verification. The uniquely identifying implementation details include GET requests without request verification. This issue is fixed in version 1.8.40."
}
],
"metrics": [
{
"cvssV3_1": {
"attackComplexity": "LOW",
"attackVector": "NETWORK",
"availabilityImpact": "LOW",
"baseScore": 4.6,
"baseSeverity": "MEDIUM",
"confidentialityImpact": "NONE",
"integrityImpact": "LOW",
"privilegesRequired": "LOW",
"scope": "UNCHANGED",
"userInteraction": "REQUIRED",
"vectorString": "CVSS:3.1/AV:N/AC:L/PR:L/UI:R/S:U/C:N/I:L/A:L",
"version": "3.1"
}
}
],
"problemTypes": [
{
"descriptions": [
{
"cweId": "CWE-352",
"description": "CWE-352: Cross-Site Request Forgery (CSRF)",
"lang": "en",
"type": "CWE"
}
]
}
],
"providerMetadata": {
"dateUpdated": "2026-08-18T15:49:14.763Z",
"orgId": "a0819718-46f1-4df5-94e2-005712e83aaa",
"shortName": "GitHub_M"
},
"references": [
{
"name": "https://github.com/mybb/mybb/security/advisories/GHSA-p48q-4vgf-q7x8",
"tags": [
"x_refsource_CONFIRM"
],
"url": "https://github.com/mybb/mybb/security/advisories/GHSA-p48q-4vgf-q7x8"
},
{
"name": "https://github.com/mybb/mybb/commit/70d445d14c8350cc014be66f7874611abef70ab4",
"tags": [
"x_refsource_MISC"
],
"url": "https://github.com/mybb/mybb/commit/70d445d14c8350cc014be66f7874611abef70ab4"
},
{
"name": "https://github.com/mybb/mybb/releases/tag/mybb_1840",
"tags": [
"x_refsource_MISC"
],
"url": "https://github.com/mybb/mybb/releases/tag/mybb_1840"
},
{
"name": "https://mybb.com/versions/1.8.40",
"tags": [
"x_refsource_MISC"
],
"url": "https://mybb.com/versions/1.8.40"
}
],
"source": {
"advisory": "GHSA-p48q-4vgf-q7x8",
"discovery": "UNKNOWN"
},
"title": "MyBB: ACP UTF-8 Conversion CSRF"
}
},
"cveMetadata": {
"assignerOrgId": "a0819718-46f1-4df5-94e2-005712e83aaa",
"assignerShortName": "GitHub_M",
"cveId": "CVE-2026-45119",
"datePublished": "2026-08-18T15:49:14.763Z",
"dateReserved": "2026-05-08T20:08:17.207Z",
"dateUpdated": "2026-08-19T14:41:09.985Z",
"state": "PUBLISHED"
},
"dataType": "CVE_RECORD",
"dataVersion": "5.2",
"vulnerability-lookup:meta": {
"epss": {
"cve": "CVE-2026-45119",
"date": "2026-08-24",
"epss": "0.00128",
"percentile": "0.02698"
},
"nvd": "{\"cve\":{\"id\":\"CVE-2026-45119\",\"sourceIdentifier\":\"security-advisories@github.com\",\"published\":\"2026-08-18T16:17:06.773\",\"lastModified\":\"2026-08-19T15:17:02.790\",\"vulnStatus\":\"Received\",\"cveTags\":[],\"descriptions\":[{\"lang\":\"en\",\"value\":\"MyBB is free and open source forum software. Prior to 1.8.40, the Admin CP UTF-8 Conversion module does not validate certain requests correctly, allowing same-site attackers to alter table encoding and deny service with a specially crafted URL. The do=all control flow in admin/modules/tools/system_health.php performs ALTER TABLE operations, column rewrite phases, and fulltext index rebuilds on GET requests for the database table named by the table parameter without request verification. The uniquely identifying implementation details include GET requests without request verification. This issue is fixed in version 1.8.40.\"}],\"affected\":[{\"source\":\"security-advisories@github.com\",\"affectedData\":[{\"vendor\":\"mybb\",\"product\":\"mybb\",\"versions\":[{\"version\":\"\u003c 1.8.40\",\"status\":\"affected\"}]}]}],\"metrics\":{\"cvssMetricV31\":[{\"source\":\"security-advisories@github.com\",\"type\":\"Secondary\",\"cvssData\":{\"version\":\"3.1\",\"vectorString\":\"CVSS:3.1/AV:N/AC:L/PR:L/UI:R/S:U/C:N/I:L/A:L\",\"baseScore\":4.6,\"baseSeverity\":\"MEDIUM\",\"attackVector\":\"NETWORK\",\"attackComplexity\":\"LOW\",\"privilegesRequired\":\"LOW\",\"userInteraction\":\"REQUIRED\",\"scope\":\"UNCHANGED\",\"confidentialityImpact\":\"NONE\",\"integrityImpact\":\"LOW\",\"availabilityImpact\":\"LOW\"},\"exploitabilityScore\":2.1,\"impactScore\":2.5}],\"ssvcV203\":[{\"source\":\"134c704f-9b21-4f2e-91b3-4a467353bcc0\",\"ssvcData\":{\"timestamp\":\"2026-08-19T14:40:56.896930Z\",\"id\":\"CVE-2026-45119\",\"options\":[{\"exploitation\":\"none\"},{\"automatable\":\"no\"},{\"technicalImpact\":\"partial\"}],\"role\":\"CISA Coordinator\",\"version\":\"2.0.3\"}}]},\"weaknesses\":[{\"source\":\"security-advisories@github.com\",\"type\":\"Secondary\",\"description\":[{\"lang\":\"en\",\"value\":\"CWE-352\"}]}],\"references\":[{\"url\":\"https://github.com/mybb/mybb/commit/70d445d14c8350cc014be66f7874611abef70ab4\",\"source\":\"security-advisories@github.com\"},{\"url\":\"https://github.com/mybb/mybb/releases/tag/mybb_1840\",\"source\":\"security-advisories@github.com\"},{\"url\":\"https://github.com/mybb/mybb/security/advisories/GHSA-p48q-4vgf-q7x8\",\"source\":\"security-advisories@github.com\"},{\"url\":\"https://mybb.com/versions/1.8.40\",\"source\":\"security-advisories@github.com\"}]}}",
"vulnrichment": {
"containers": "{\"adp\": [{\"title\": \"CISA ADP Vulnrichment\", \"metrics\": [{\"other\": {\"type\": \"ssvc\", \"content\": {\"id\": \"CVE-2026-45119\", \"role\": \"CISA Coordinator\", \"options\": [{\"Exploitation\": \"none\"}, {\"Automatable\": \"no\"}, {\"Technical Impact\": \"partial\"}], \"version\": \"2.0.3\", \"timestamp\": \"2026-08-19T14:40:56.896930Z\"}}}], \"providerMetadata\": {\"orgId\": \"134c704f-9b21-4f2e-91b3-4a467353bcc0\", \"shortName\": \"CISA-ADP\", \"dateUpdated\": \"2026-08-19T14:41:04.400Z\"}}], \"cna\": {\"title\": \"MyBB: ACP UTF-8 Conversion CSRF\", \"source\": {\"advisory\": \"GHSA-p48q-4vgf-q7x8\", \"discovery\": \"UNKNOWN\"}, \"metrics\": [{\"cvssV3_1\": {\"scope\": \"UNCHANGED\", \"version\": \"3.1\", \"baseScore\": 4.6, \"attackVector\": \"NETWORK\", \"baseSeverity\": \"MEDIUM\", \"vectorString\": \"CVSS:3.1/AV:N/AC:L/PR:L/UI:R/S:U/C:N/I:L/A:L\", \"integrityImpact\": \"LOW\", \"userInteraction\": \"REQUIRED\", \"attackComplexity\": \"LOW\", \"availabilityImpact\": \"LOW\", \"privilegesRequired\": \"LOW\", \"confidentialityImpact\": \"NONE\"}}], \"affected\": [{\"vendor\": \"mybb\", \"product\": \"mybb\", \"versions\": [{\"status\": \"affected\", \"version\": \"\u003c 1.8.40\"}]}], \"references\": [{\"url\": \"https://github.com/mybb/mybb/security/advisories/GHSA-p48q-4vgf-q7x8\", \"name\": \"https://github.com/mybb/mybb/security/advisories/GHSA-p48q-4vgf-q7x8\", \"tags\": [\"x_refsource_CONFIRM\"]}, {\"url\": \"https://github.com/mybb/mybb/commit/70d445d14c8350cc014be66f7874611abef70ab4\", \"name\": \"https://github.com/mybb/mybb/commit/70d445d14c8350cc014be66f7874611abef70ab4\", \"tags\": [\"x_refsource_MISC\"]}, {\"url\": \"https://github.com/mybb/mybb/releases/tag/mybb_1840\", \"name\": \"https://github.com/mybb/mybb/releases/tag/mybb_1840\", \"tags\": [\"x_refsource_MISC\"]}, {\"url\": \"https://mybb.com/versions/1.8.40\", \"name\": \"https://mybb.com/versions/1.8.40\", \"tags\": [\"x_refsource_MISC\"]}], \"descriptions\": [{\"lang\": \"en\", \"value\": \"MyBB is free and open source forum software. Prior to 1.8.40, the Admin CP UTF-8 Conversion module does not validate certain requests correctly, allowing same-site attackers to alter table encoding and deny service with a specially crafted URL. The do=all control flow in admin/modules/tools/system_health.php performs ALTER TABLE operations, column rewrite phases, and fulltext index rebuilds on GET requests for the database table named by the table parameter without request verification. The uniquely identifying implementation details include GET requests without request verification. This issue is fixed in version 1.8.40.\"}], \"problemTypes\": [{\"descriptions\": [{\"lang\": \"en\", \"type\": \"CWE\", \"cweId\": \"CWE-352\", \"description\": \"CWE-352: Cross-Site Request Forgery (CSRF)\"}]}], \"providerMetadata\": {\"orgId\": \"a0819718-46f1-4df5-94e2-005712e83aaa\", \"shortName\": \"GitHub_M\", \"dateUpdated\": \"2026-08-18T15:49:14.763Z\"}}}",
"cveMetadata": "{\"cveId\": \"CVE-2026-45119\", \"state\": \"PUBLISHED\", \"dateUpdated\": \"2026-08-19T14:41:09.985Z\", \"dateReserved\": \"2026-05-08T20:08:17.207Z\", \"assignerOrgId\": \"a0819718-46f1-4df5-94e2-005712e83aaa\", \"datePublished\": \"2026-08-18T15:49:14.763Z\", \"assignerShortName\": \"GitHub_M\"}",
"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.
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.
Loading…
Loading…