GHSA-5957-c7qm-m469

Suggest an improvement
Source
https://github.com/advisories/GHSA-5957-c7qm-m469
Import Source
https://github.com/github/advisory-database/blob/main/advisories/github-reviewed/2026/11/GHSA-5957-c7qm-m469/GHSA-5957-c7qm-m469.json
JSON Data
https://api.osv.dev/v1/vulns/GHSA-5957-c7qm-m469
Aliases
  • CVE-2026-126068
Published
2026-11-10T21:28:16Z
Modified
2026-11-10T21:45:04Z
Severity
  • 3.7 (Low) CVSS_V3 - CVSS:3.1/AV:N/AC:H/PR:N/UI:N/S:U/C:N/I:L/A:N CVSS Calculator
Summary
Action Mailbox: Possible signature replay in Action Mailbox Mailgun ingress
Details

Impact

The Action Mailbox Mailgun ingress authenticates a request with an HMAC of the timestamp and token parameters concatenated without a separator, and ActionMailbox::Ingresses::Mailgun::InboundEmailsController::Authenticator#recent? rejects only timestamps more than 2 minutes in the past. Because the signature does not fix the boundary between the two values, a captured signed request can be presented with a timestamp far in the future, which the ingress then accepts indefinitely. An attacker who obtains one signed Mailgun webhook request, but not the signing key, could submit arbitrary inbound email that Action Mailbox processes as genuine, possibly leading to forged messages attributed to the sender of the attacker's choosing.

Applications that receive inbound email through the Action Mailbox Mailgun ingress are affected.

Details

The fixed releases also reject a Mailgun request whose timestamp is more than 2 minutes ahead of the server's clock, as they already did for one more than 2 minutes behind it. An application whose clock runs more than 2 minutes behind Mailgun's will now reject genuine webhooks and should synchronize its clock.

Releases

The fixed releases are available at the normal locations.

Patches for those who cannot upgrade at once:

Credit

This issue was responsibly reported by HackerOne researcher davutselcuk.

Database specific 
{
    "cwe_ids": [
        "CWE-294"
    ],
    "github_reviewed": true,
    "github_reviewed_at": "2026-11-10T21:28:16Z",
    "nvd_published_at": null,
    "severity": "LOW"
}
References

Affected packages

RubyGems / actionmailbox

Package

Name
actionmailbox
Purl
pkg:gem/actionmailbox

Affected ranges

Type
ECOSYSTEM
Events
Introduced
8.1.0.beta1
Fixed
8.1.4.1

Affected versions

8.*
8.1.0.beta1
8.1.0.rc1
8.1.0
8.1.1
8.1.2
8.1.2.1
8.1.3
8.1.3.1
8.1.4

Database specific

source 
"https://github.com/github/advisory-database/blob/main/advisories/github-reviewed/2026/11/GHSA-5957-c7qm-m469/GHSA-5957-c7qm-m469.json"

RubyGems / actionmailbox

Package

Name
actionmailbox
Purl
pkg:gem/actionmailbox

Affected ranges

Type
ECOSYSTEM
Events
Introduced
0 Unknown introduced version / All previous versions are affected
Fixed
8.0.5.2

Affected versions

0.*
0.1.0
6.*
6.0.0.beta1
6.0.0.beta2
6.0.0.beta3
6.0.0.rc1
6.0.0.rc2
6.0.0
6.0.1.rc1
6.0.1
6.0.2.rc1
6.0.2.rc2
6.0.2
6.0.2.1
6.0.2.2
6.0.3.rc1
6.0.3
6.0.3.1
6.0.3.2
6.0.3.3
6.0.3.4
6.0.3.5
6.0.3.6
6.0.3.7
6.0.4
6.0.4.1
6.0.4.2
6.0.4.3
6.0.4.4
6.0.4.5
6.0.4.6
6.0.4.7
6.0.4.8
6.0.5
6.0.5.1
6.0.6
6.0.6.1
6.1.0.rc1
6.1.0.rc2
6.1.0
6.1.1
6.1.2
6.1.2.1
6.1.3
6.1.3.1
6.1.3.2
6.1.4
6.1.4.1
6.1.4.2
6.1.4.3
6.1.4.4
6.1.4.5
6.1.4.6
6.1.4.7
6.1.5
6.1.5.1
6.1.6
6.1.6.1
6.1.7
6.1.7.1
6.1.7.2
6.1.7.3
6.1.7.4
6.1.7.5
6.1.7.6
6.1.7.7
6.1.7.8
6.1.7.9
6.1.7.10
7.*
7.0.0.alpha1
7.0.0.alpha2
7.0.0.rc1
7.0.0.rc2
7.0.0.rc3
7.0.0
7.0.1
7.0.2
7.0.2.1
7.0.2.2
7.0.2.3
7.0.2.4
7.0.3
7.0.3.1
7.0.4
7.0.4.1
7.0.4.2
7.0.4.3
7.0.5
7.0.5.1
7.0.6
7.0.7
7.0.7.1
7.0.7.2
7.0.8
7.0.8.1
7.0.8.2
7.0.8.3
7.0.8.4
7.0.8.5
7.0.8.6
7.0.8.7
7.0.10
7.1.0.beta1
7.1.0.rc1
7.1.0.rc2
7.1.0
7.1.1
7.1.2
7.1.3
7.1.3.1
7.1.3.2
7.1.3.3
7.1.3.4
7.1.4
7.1.4.1
7.1.4.2
7.1.5
7.1.5.1
7.1.5.2
7.1.6
7.2.0.beta1
7.2.0.beta2
7.2.0.beta3
7.2.0.rc1
7.2.0
7.2.1
7.2.1.1
7.2.1.2
7.2.2
7.2.2.1
7.2.2.2
7.2.3
7.2.3.1
7.2.3.2
7.2.4
8.*
8.0.0.beta1
8.0.0.rc1
8.0.0.rc2
8.0.0
8.0.0.1
8.0.1
8.0.2
8.0.2.1
8.0.3
8.0.4
8.0.4.1
8.0.5
8.0.5.1

Database specific

source 
"https://github.com/github/advisory-database/blob/main/advisories/github-reviewed/2026/11/GHSA-5957-c7qm-m469/GHSA-5957-c7qm-m469.json"