CVE-2026-30796
RustDesk Client Transmits Preset Address Book Password Verbatim in Heartbeat Sync
Cleartext Transmission of Sensitive Information, Insufficiently Protected Credentials vulnerability in rustdesk-client RustDesk Client rustdesk-client on Windows, MacOS, Linux, iOS, Android (Address book sync, Heartbeat sync loop modules) allows Sniffing Attacks.
The client places the preset address-book password verbatim into the heartbeat sync JSON body (src/hbbs_http/sync.rs). Over an intact HTTPS session it is not exposed in transit, but it is a reusable shared secret rather than a zero-knowledge proof, so it is recovered by any party that becomes the API endpoint - under the re-homed/rogue API server (CVE-2026-30797) - and the leaked credential then authorizes the server-side address book.
This vulnerability is associated with program files src/hbbs_http/sync.rs and program routines heartbeat sync body builder (emits preset-address-book-password).
This issue affects RustDesk Client: through 1.4.8.
Attack profile
How easy it is to exploit
- Attack vector
- Network
- Complexity
- Low
- Privileges needed
- None
- User interaction
- None
What an attacker can affect
- Confidentiality
- None
- Integrity
- None
- Availability
- None
Exploit likelihood
What each source reports
CVE List Score used
6.9
RustDesk Client Transmits Preset Address Book Password Verbatim in Heartbeat Sync
Cleartext Transmission of Sensitive Information, Insufficiently Protected Credentials vulnerability in rustdesk-client RustDesk Client rustdesk-client on Windows, MacOS, Linux, iOS, Android (Address book sync, Heartbeat sync loop modules) allows Sniffing Attacks.
The client places the preset address-book password verbatim into the heartbeat sync JSON body (src/hbbs_http/sync.rs). Over an intact HTTPS session it is not exposed in transit, but it is a reusable shared secret rather than a zero-knowledge proof, so it is recovered by any party that becomes the API endpoint - under the re-homed/rogue API server (CVE-2026-30797) - and the leaked credential then authorizes the server-side address book.
This vulnerability is associated with program files src/hbbs_http/sync.rs and program routines heartbeat sync body builder (emits preset-address-book-password).
This issue affects RustDesk Client: through 1.4.8.
- Record
CVE-2026-30796- CVSS 4.0
- 6.9 Medium
CVSS:4.0/AV:N/AC:L/AT:P/PR:N/UI:N/VC:N/VI:N/VA:N/SC:H/SI:N/SA:N - Weakness
- CWE-522
- Updated
- 2026-11-02
EUVDEUVD-2026-9836
6.9
Cleartext Transmission of Sensitive Information, Insufficiently Protected Credentials vulnerability in rustdesk-client RustDesk Client rustdesk-client on Windows, MacOS, Linux, iOS, Android (Address book sync, Heartbeat sync loop modules) allows Sniffing Attacks.
The client places the preset address-book password verbatim into the heartbeat sync JSON body (src/hbbs_http/sync.rs). Over an intact HTTPS session it is not exposed in transit, but it is a reusable shared secret rather than a zero-knowledge proof, so it is recovered by any party that becomes the API endpoint - under the re-homed/rogue API server (CVE-2026-30797) - and the leaked credential then authorizes the server-side address book.
This vulnerability is associated with program files src/hbbs_http/sync.rs and program routines heartbeat sync body builder (emits preset-address-book-password).
This issue affects RustDesk Client: through 1.4.8.
- Record
EUVD-2026-9836- CVSS 4.0
- 6.9 Medium
CVSS:4.0/AV:N/AC:L/AT:P/PR:N/UI:N/VC:N/VI:N/VA:N/SC:H/SI:N/SA:N - Updated
- 2026-11-02
GitHub AdvisoriesGHSA-v69h-c25q-f3jf
8.7
Cleartext Transmission of Sensitive Information vulnerability in rustdesk-server-pro RustDesk...
Cleartext Transmission of Sensitive Information vulnerability in rustdesk-server-pro RustDesk Server Pro rustdesk-server-pro on Windows, MacOS, Linux (Address book sync API modules) allows Sniffing Attacks. This vulnerability is associated with program files Closed source — API endpoint handling heartbeat sync and program routines Heartbeat API handler (accepts preset-address-book-password in plaintext).
This issue affects RustDesk Server Pro: through 1.7.5.
- Record
GHSA-v69h-c25q-f3jf- CVSS 4.0
- 8.7 High
CVSS:4.0/AV:N/AC:L/AT:N/PR:N/UI:N/VC:H/VI:N/VA:N/SC:N/SI:N/SA:N/E:X/CR:X/IR:X/AR:X/MAV:X/MAC:X/MAT:X/MPR:X/MUI:X/MVC:X/MVI:X/MVA:X/MSC:X/MSI:X/MSA:X/S:X/AU:X/R:X/V:X/RE:X/U:X - CVSS 3.1
- 7.5 High
CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:N/A:N - Weakness
- CWE-319, CWE-522
- Updated
- 2026-11-02
NVD
6.9
Cleartext Transmission of Sensitive Information, Insufficiently Protected Credentials vulnerability in rustdesk-client RustDesk Client rustdesk-client on Windows, MacOS, Linux, iOS, Android (Address book sync, Heartbeat sync loop modules) allows Sniffing Attacks.
The client places the preset address-book password verbatim into the heartbeat sync JSON body (src/hbbs_http/sync.rs). Over an intact HTTPS session it is not exposed in transit, but it is a reusable shared secret rather than a zero-knowledge proof, so it is recovered by any party that becomes the API endpoint - under the re-homed/rogue API server (CVE-2026-30797) - and the leaked credential then authorizes the server-side address book.
This vulnerability is associated with program files src/hbbs_http/sync.rs and program routines heartbeat sync body builder (emits preset-address-book-password).
This issue affects RustDesk Client: through 1.4.8.
- Record
CVE-2026-30796- CVSS 4.0
- 6.9 Medium
CVSS:4.0/AV:N/AC:L/AT:P/PR:N/UI:N/VC:N/VI:N/VA:N/SC:H/SI:N/SA:N/E:X/CR:X/IR:X/AR:X/MAV:X/MAC:X/MAT:X/MPR:X/MUI:X/MVC:X/MVI:X/MVA:X/MSC:X/MSI:X/MSA:X/S:X/AU:X/R:X/V:X/RE:X/U:X - CVSS 3.1
- 7.5 High
CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:N/A:N - Weakness
- CWE-522
- Updated
- 2026-11-02
OSV
6.9
RustDesk Client Transmits Preset Address Book Password Verbatim in Heartbeat Sync
Cleartext Transmission of Sensitive Information, Insufficiently Protected Credentials vulnerability in rustdesk-client RustDesk Client rustdesk-client on Windows, MacOS, Linux, iOS, Android (Address book sync, Heartbeat sync loop modules) allows Sniffing Attacks.
The client places the preset address-book password verbatim into the heartbeat sync JSON body (src/hbbs_http/sync.rs). Over an intact HTTPS session it is not exposed in transit, but it is a reusable shared secret rather than a zero-knowledge proof, so it is recovered by any party that becomes the API endpoint - under the re-homed/rogue API server (CVE-2026-30797) - and the leaked credential then authorizes the server-side address book.
This vulnerability is associated with program files src/hbbs_http/sync.rs and program routines heartbeat sync body builder (emits preset-address-book-password).
This issue affects RustDesk Client: through 1.4.8.
- Record
CVE-2026-30796- CVSS 4.0
- 6.9 Medium
CVSS:4.0/AV:N/AC:L/AT:P/PR:N/UI:N/VC:N/VI:N/VA:N/SC:H/SI:N/SA:N - Weakness
- CWE-522
- Updated
- 2026-11-02
Affected products
History
| Recorded | Changed | Sources |
|---|---|---|
| first indexed | CVE List, EUVD, GitHub Advisories, NVD, OSV |
Dates are when Every CVE recorded each change. Upstream dates may differ.
In short
CVE-2026-30796 is a medium vulnerability (CVSS 6.9) in Rustdesk Server, published March 5, 2026. No source lists public exploit code. EPSS puts the chance of exploitation in the next 30 days at 0.46%, the 40th percentile. No source names a fixed version.
References
rustdesk.com/docs/en
docs.google.com/document/d/e/2PACX-1vSds6jjpd38oO_yIAyd1HYtKNUuea-I-ozAPpGhYI7QgAU-QGJ7D8a4rOZVj1vmiUXV1EcdRHf9aZAW/pub
vulsec.org
nvd.nist.gov/vuln/detail/CVE-2026-30796
github.com/advisories/GHSA-v69h-c25q-f3jf
github.com/rustdesk/rustdesk,https://github.com/rustdesk/hbb_common
github.com/CVEProject/cvelistV5/tree/main/cves/2026/30xxx/CVE-2026-30796.json
github.com/rustdesk/rustdesk/releases