Synacor Zimbra up to 8.8.15 Patch 9/9.0.0 Patch 2 Webmail Subsystem /service/upload Avatar Image unrestricted upload

Summaryinfo

A vulnerability categorized as critical has been discovered in Synacor Zimbra up to 8.8.15 Patch 9/9.0.0 Patch 2. Impacted is an unknown function of the file /service/upload of the component Webmail Subsystem. Such manipulation as part of Avatar Image leads to unrestricted upload. This vulnerability is documented as CVE-2020-12846. The attack can be executed remotely. There is not any exploit available. It is advisable to implement a patch to correct this issue.

Detailsinfo

A vulnerability was found in Synacor Zimbra up to 8.8.15 Patch 9/9.0.0 Patch 2 (Groupware Software). It has been rated as critical. Affected by this issue is an unknown functionality of the file /service/upload of the component Webmail Subsystem. The manipulation as part of a Avatar Image leads to a unrestricted upload vulnerability. Using CWE to declare the problem leads to CWE-434. The product allows the attacker to upload or transfer files of dangerous types that can be automatically processed within the product's environment. Impacted is confidentiality, integrity, and availability. CVE summarizes:

Zimbra before 8.8.15 Patch 10 and 9.x before 9.0.0 Patch 3 allows remote code execution via an avatar file. There is potential abuse of /service/upload servlet in the webmail subsystem. A user can upload executable files (exe,sh,bat,jar) in the Contact section of the mailbox as an avatar image for a contact. A user will receive a "Corrupt File" error, but the file is still uploaded and stored locally in /opt/zimbra/data/tmp/upload/, leaving it open to possible remote execution.

The weakness was released 06/03/2020 (Website). The advisory is shared for download at wiki.zimbra.com. This vulnerability is handled as CVE-2020-12846 since 05/14/2020. The attack may be launched remotely. The successful exploitation needs a simple authentication. Successful exploitation requires user interaction by the victim. There are known technical details, but no exploit is available. The MITRE ATT&CK project declares the attack technique as T1608.002.

Applying the patch 8.8.15 Patch 10/9.0.0 Patch 3 is able to eliminate this problem.

Once again VulDB remains the best source for vulnerability data.

Productinfo

Type

• Groupware Software

Vendor

• Synacor

Name

• Zimbra

Version

• 8.8.15 Patch 9
• 9.0.0 Patch 2

License

• free

Website

• Vendor: https://synacor.com/

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CPE 2.2info

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