trustbuilder-appimage
The PKGBUILD downloads a prebuilt AppImage binary from download.trustbuilder.com, which is the vendor's own download subdomain (trustbuilder.com is the official product website listed in the url= field). The binary is extracted and executed during prepare() via --appimage-extract, and the AppImage itself is installed and symlinked as the user-facing executable. A sha256sum is provided, which pins the specific artifact. The concern is that this is a closed-source prebuilt binary from a vendor download host rather than a source build or an official distro mirror — if the host were compromised or the vendor pushed a silent update, the checksum would catch it only for the pinned version. The license field claims GPL but this is a proprietary authenticator product, which is suspicious but not necessarily malicious. Overall this fits the classic AUR AppImage pattern: a real supply-chain concern (executed binary from a vendor host, no source build) but not an active attack, so MEDIUM is appropriate.
Triggered rules
source_untrusted_domain
One or more source=() URLs point to a host outside the trusted allowlist (github.com, gitlab.com, codeberg.org, pypi.org, …).
-
PKGBUILD:16
source=("${_appimage}::https://download.trustbuilder.com/wp-content/uploads/${_appimage}")
llm_review
An AI model (anthropic/claude-4.6-sonnet-20260217) reviewed this and agrees it is MEDIUM (confidence 72%): The PKGBUILD downloads a prebuilt AppImage binary from download.trustbuilder.com, which is the vendor's own download subdomain (trustbuilder.com is the official product website listed in the url= field). The binary is extracted and executed during prepare() via --appimage-extract, and the AppImage itself is installed and symlinked as the user-facing executable. A sha256sum is provided, which pins the specific artifact. The concern is that this is a closed-source prebuilt binary from a vendor download host rather than a source build or an official distro mirror — if the host were compromised or the vendor pushed a silent update, the checksum would catch it only for the pinned version. The license field claims GPL but this is a proprietary authenticator product, which is suspicious but not necessarily malicious. Overall this fits the classic AUR AppImage pattern: a real supply-chain concern (executed binary from a vendor host, no source build) but not an active attack, so MEDIUM is appropriate.
PKGBUILD
1 offending line(s) highlighted# Maintainer: Vincent Bauchart <vincent.bauchart at tutanota dot com>
_pkgname=trustbuilder
pkgname=trustbuilder-appimage
pkgver=6.38.0.5319
pkgrel=2
pkgdesc='Trustbuilder Authenticator / AppImage version'
arch=(x86_64)
url=https://www.trustbuilder.com/
license=(GPL)
_appimage="Authenticator6-Linux.AppImage"
noextract=("${_appimage}")
provides=('trustbuilder')
depends=('fuse2')
conflicts=('trustbuilder')
options=(!strip !debug)
source=("${_appimage}::https://download.trustbuilder.com/wp-content/uploads/${_appimage}")
sha256sums=('e05796e8ddcf072afca303eb022931510b59dde9ae6e64e812cbad8ccc584c73')
appname="trustbuilder"
prepare() {
chmod +x "${_appimage}"
./"${_appimage}" --appimage-extract
}
build() {
# Adjust .desktop so it will work outside of AppImage container
sed -i -E "s|Exec=.*|Exec=/usr/bin/${appname} %U|"\
"squashfs-root/authenticator 6.desktop"
# We need to match the WMClass of the AppImage which is different from the provided desktop file
sed -i -E "s|StartupWMClass=.*|StartupWMClass=Authenticator 6|"\
"squashfs-root/authenticator 6.desktop"
# Fix permissions; .AppImage permissions are 700 for all directories
chmod -R a-x+rX squashfs-root/usr
}
package() {
# AppImage
install -Dm755 "${srcdir}/${_appimage}" "${pkgdir}/opt/${pkgname}/${pkgname}.AppImage"
# Desktop file
install -Dm644 "${srcdir}/squashfs-root/authenticator 6.desktop"\
"${pkgdir}/usr/share/applications/${appname}.desktop"
# Icon image
install -dm755 "${pkgdir}/usr/share/icons/"
cp -a "${srcdir}/squashfs-root/usr/share/icons/hicolor/0x0/apps/authenticator 6.png" "${pkgdir}/usr/share/icons"
# Symlink executable
install -dm755 "${pkgdir}/usr/bin"
ln -s "/opt/${pkgname}/${pkgname}.AppImage" "${pkgdir}/usr/bin/${appname}"
}
pkgver() {
grep "X-AppImage-Version" "${srcdir}/squashfs-root/authenticator 6.desktop" | sed 's/.*=\(.*\)/\1/'
}
Scan history
| Scanned at (UTC) | Severity | Rules |
|---|---|---|
| 2026-11-01 00:21:48 | Medium | 2 |
| 2026-10-31 00:07:41 | Medium | 2 |
| 2026-10-30 00:29:30 | Medium | 2 |
| 2026-10-29 00:13:55 | Medium | 2 |
| 2026-10-28 00:06:54 | Medium | 2 |
| 2026-10-27 00:23:28 | Medium | 2 |
| 2026-10-26 00:12:40 | Medium | 2 |
| 2026-10-25 00:20:48 | Medium | 2 |
| 2026-10-24 00:14:55 | Medium | 2 |
| 2026-10-23 00:02:19 | Medium | 2 |
| 2026-10-22 00:13:10 | Medium | 2 |
| 2026-10-21 00:12:50 | Medium | 2 |
| 2026-10-20 00:10:31 | Medium | 2 |
| 2026-10-19 00:03:55 | Medium | 2 |
| 2026-10-18 00:06:55 | Medium | 2 |
| 2026-10-17 00:21:55 | Medium | 2 |
| 2026-10-16 00:12:47 | Medium | 2 |
| 2026-10-15 00:28:05 | Medium | 2 |
| 2026-10-14 00:06:47 | Medium | 2 |
| 2026-10-13 00:23:45 | Medium | 2 |