Critical
Group-Office: Authenticated Remote Code Execution via PHP Insecure Deserialization in `AbstractSettingsCollection`
Type: advisorySources: OSV
Group-Office is an enterprise customer relationship management and groupware tool. Prior to versions 6.8.156, 25.0.90, and 26.0.12, a vulnerability in the AbstractSettingsCollection model leads to insecure deserialization when these settings are loaded. By injecting a serialized FileCookieJar object into a setting string, an authenticated attacker can achieve Arbitrary File Write, leading directly to Remote Code Execution (RCE) on the server. This issue has been patched in versions 6.8.156, 25.0.90, and 26.0.12.
- Products
- Not specified
- Affected versions
- Not specified
- Fixed versions
- Not specified
- CVEs
- CVE-2026-34838
- Confirmed fixed CVEs
- Not specified
- Updated in this feed
- 8 Nov 2026, 01:59 UTC · Revision 1
Source evidence
Group-Office: Authenticated Remote Code Execution via PHP Insecure Deserialization in `AbstractSettingsCollection`
core-osv · Original sourcePublished 2 Apr 2026, 19:15 UTC
Group-Office is an enterprise customer relationship management and groupware tool. Prior to versions 6.8.156, 25.0.90, and 26.0.12, a vulnerability in the AbstractSettingsCollection model leads to insecure deserialization when these settings are loaded. By injecting a serialized FileCookieJar object into a setting string, an authenticated attacker can achieve Arbitrary File Write, leading directly to Remote Code Execution (RCE) on the server. This issue has been patched in versions 6.8.156, 25.0.90, and 26.0.12.
osv:CVE-2026-34838
Complete source record
{
"id": "2fe410b71b6df9c073e7b32ea5e8ee78ac79ad9c2645ae1f31798e072393e36d",
"url": "https://osv.dev/vulnerability/CVE-2026-34838",
"method": "structured",
"payload": {
"kind": "advisory",
"title": "Group-Office: Authenticated Remote Code Execution via PHP Insecure Deserialization in `AbstractSettingsCollection`",
"summary": "Group-Office is an enterprise customer relationship management and groupware tool. Prior to versions 6.8.156, 25.0.90, and 26.0.12, a vulnerability in the AbstractSettingsCollection model leads to insecure deserialization when these settings are loaded. By injecting a serialized FileCookieJar object into a setting string, an authenticated attacker can achieve Arbitrary File Write, leading directly to Remote Code Execution (RCE) on the server. This issue has been patched in versions 6.8.156, 25.0.90, and 26.0.12.",
"evidence": "osv:CVE-2026-34838",
"products": [],
"severity": "critical",
"structured": {
"id": "CVE-2026-34838",
"aliases": [
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"GHSA-h22j-frrf-5vxq"
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"score": "CVSS:3.1/AV:N/AC:L/PR:L/UI:N/S:C/C:H/I:H/A:H"
}
],
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{
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"repo": "https://github.com/intermesh/groupoffice",
"type": "GIT",
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],
"modified": "2026-10-28T02:30:53.133846734Z",
"provider": "osv",
"references": [
"https://github.com/Intermesh/groupoffice/releases/tag/v25.0.90",
"https://github.com/Intermesh/groupoffice/releases/tag/v26.0.12",
"https://github.com/Intermesh/groupoffice/releases/tag/v6.8.156",
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"https://nvd.nist.gov/vuln/detail/CVE-2026-34838"
],
"provider_metadata": {
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"cna_assigner": "GitHub_M",
"osv_generated_from": "https://github.com/CVEProject/cvelistV5/tree/main/cves/2026/34xxx/CVE-2026-34838.json"
}
},
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"evidence": "/id"
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},
"source_id": "core-osv",
"document_id": 521575,
"published_at": "2026-04-02T19:15:40.591+00:00"
}