CVE-2020-8866

mediumpriority · track · 39EPSS 0.096 · 95 %ileexploit · PoCEUUS

grimoire priorityP1 · Urgent

Exploitable?

Public exploit

2 exploits · PoC

Likely / severe?

9.58% (95th) EPSS

CVSS 4 · medium

Is it mine?

4 products

Check your exposure

Who says so?

3 sources

cnnvd · enisa_euvd · nvd

EPSS · scored 2026-10-28

This vulnerability allows remote attackers to create arbitrary files on affected installations of Horde Groupware Webmail Edition 5.2.22. Authentication is required to exploit this vulnerability. The specific flaw exists within add.php. The issue results from the lack of proper validation of user-supplied data, which can allow the upload of arbitrary files. An attacker can leverage this in conjunction with other vulnerabilities to execute code in the context of the www-data user. Was ZDI-CAN-10125.

cvss

Technical severity, 0–10. One row per scoring source.

6.5

010

base score 0–10 · higher = more severe · hover a vector to decode

v2.04mediumAV:N/AC:L/Au:S/C:N/I:P/A:Nprimary · NVD / NIST USexploitability 8 · impact 2.9

v3.16.5mediumCVSS:3.1/AV:N/AC:L/PR:L/UI:N/S:U/C:N/I:H/A:Nprimary · NVD / NIST USexploitability 2.8 · impact 3.6

v3.04.3mediumCVSS:3.0/AV:N/AC:L/PR:L/UI:N/S:U/C:N/I:L/A:Nsecondary · ENISA EU

v3.04.3mediumCVSS:3.0/AV:N/AC:L/PR:L/UI:N/S:U/C:N/I:L/A:Nsecondary · zdi-disclosures@trendmicro.comexploitability 2.8 · impact 1.4

v3.16.2mediumCVSS:3.1/AV:N/AC:L/PR:L/UI:N/S:U/C:N/I:H/A:N/E:Psecondary · CVSS-BT (t0sche)

weaknesses

The CWE weakness classes this flaw belongs to.

CWE-434USprimary

exploits (2)

Public proof-of-concept and weaponised exploit code.

EDB-48209Horde Groupware Webmail Edition 5.2.22 - PHP File InclusionPoC · exploit_db
EDB-48210Horde Groupware Webmail Edition 5.2.22 - PHAR LoadingPoC · exploit_db

affected products (4)

Products and version ranges known to be affected.

Horde Groupware Webmail Edition≤ 5.2.22enisa_euvdEU
debian debian linux= 8.0nvdUScpe:2.3:o:debian:debian_linux:*:*:*:*:*:*:*:*
horde groupware= 5.2.22nvdUScpe:2.3:a:horde:groupware:*:*:*:*:*:*:*:*
horde horde form< 2.0.20nvdUScpe:2.3:a:horde:horde_form:*:*:*:*:*:*:*:*

also known as (3)

Other names and identifiers for this entity.

sources

Which sources assert this record, and when.

cnnvd enisa_euvd nvd NVD CVE.org MITRE

published 2020-03-23modified 2026-06-17

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+5032 more

references (14)

External citations — patches, advisories, analysis.

scry

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