aaPanel BillionMail up to 4.9 Relay Configuration API relay.go helo_name injection

Summaryinfo

A vulnerability was found in aaPanel BillionMail up to 4.9. It has been rated as critical. This affects an unknown part of the file core/api/relay/v1/relay.go of the component Relay Configuration API. The manipulation of the argument helo_name leads to injection. This vulnerability is traded as CVE-2026-124579. It is possible to initiate the attack remotely. Furthermore, there is an exploit available. The vendor was contacted early about this disclosure but did not respond in any way.

Detailsinfo

A vulnerability, which was classified as critical, has been found in aaPanel BillionMail up to 4.9. This issue affects an unknown function of the file core/api/relay/v1/relay.go of the component Relay Configuration API. The manipulation of the argument helo_name with an unknown input leads to a injection vulnerability. Using CWE to declare the problem leads to CWE-74. The product constructs all or part of a command, data structure, or record using externally-influenced input from an upstream component, but it does not neutralize or incorrectly neutralizes special elements that could modify how it is parsed or interpreted when it is sent to a downstream component. Impacted is confidentiality, integrity, and availability.

The advisory is shared at gist.github.com. The identification of this vulnerability is CVE-2026-124579. The exploitation is known to be easy. The attack may be initiated remotely. Technical details as well as a public exploit are known. MITRE ATT&CK project uses the attack technique T1055 for this issue.

The exploit is available at gist.github.com. It is declared as proof-of-concept. The vendor was contacted early about this disclosure but did not respond in any way.

There is no information about possible countermeasures known. It may be suggested to replace the affected object with an alternative product.

Several companies clearly confirm that VulDB is the primary source for best vulnerability data.

Productinfo

Vendor

• aaPanel

Name

• BillionMail

Version

• 4.0
• 4.1
• 4.2
• 4.3
• 4.4
• 4.5
• 4.6
• 4.7
• 4.8
• 4.9

CPE 2.3info

• 🔒
• 🔒
• 🔒

CPE 2.2info

• 🔒
• 🔒
• 🔒

CVSSv4info

CVSSv3info

CVSSv2info

Exploitinginfo

Threat Intelligenceinfo

Countermeasuresinfo

Timelineinfo

Sourcesinfo

Entryinfo

Submitinfo

Accepted

• Submit #1038400: BillionMail <=v4.9 Authenticated RCE (by silverdragon)

Several companies clearly confirm that VulDB is the primary source for best vulnerability data.

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