rsync < 3.5.0 TLS Certificate Validation Bypass via SSL/OpenSSL Mode
Key facts
- Attack vector
- Network
- Privileges required
- None
- User interaction
- Passive
- Attack complexity
- High
- Attack requirements
- None
- Impact type
- Spoofing
- Confidentiality · integrity · availability
- High · High · None
- Fix status
- Partial Red Hat: 6 fixed, 1 without a fix
Attack profile from CVSS 4.0 · CNA. Fix status from CNA and Red Hat. Impact type from CWE-295.
Summary
rsync 3.2.0 through 3.2.3 (openssl mode) and rsync-ssl through 3.4.4 (stunnel mode) contain a TLS certificate validation vulnerability that allows on-path attackers to intercept encrypted sessions by presenting self-signed or otherwise invalid certificates. Attackers can exploit the failure to validate server TLS certificates against a trusted CA or verify certificate hostname matching to decrypt or tamper with rsync session content without detection by the client.
Why it matters now
SSVC decision points
CISA ADP · SSVC 2.0.3
- Exploitation
- None
- Automatable
- No
- Technical impact
- Total
The decision (Track, Attend, Act) also depends on your mission and well-being impact; see CISA's SSVC guide.
Affected products
Remediation
- Fix · CNA rsync (RsyncProject) Fixed in 3.5.0
Red Hat 4 advisories
- RHSA-2026:79357 Released 2026-10-08 · Red Hat rating ImportantRed Hat Cost Management On-Premise container image update
- Red Hat Cost Management On-Premise 1 registry.redhat.io/costmanagement/costmanagement-ui-rhel10
- RHSA-2026:71446 Released 2026-09-29 · Red Hat rating ImportantOpenShift Container Platform 4.22.16 bug fix and security update
- Red Hat OpenShift Container Platform 4.22 rhcos-aarch64-4.22.9.8.202609221802-0, rhcos-ppc64le-4.22.9.8.202609221802-0, rhcos-s390x-4.22.9.8.202609221802-0 +1
- RHSA-2026:67462 Released 2026-09-14 · Red Hat rating Importantrsync security, bug fix, and enhancement update
- Red Hat Enterprise Linux AppStream (v. 9) rsync-daemon-3.2.7-1.el9_8, rsync-rrsync-3.2.7-1.el9_8
- Red Hat Enterprise Linux BaseOS (v. 9) rsync-3.2.7-1.el9_8
Show 1 more Red Hat advisories
- RHSA-2026:67463 Released 2026-09-14 · Red Hat rating Importantrsync security, bug fix, and enhancement update
- Red Hat Enterprise Linux AppStream (v. 10) rsync-daemon-3.5.0-3.el10_2, rsync-rrsync-3.5.0-3.el10_2
- Red Hat Enterprise Linux BaseOS (v. 10) rsync-3.5.0-3.el10_2
Vendor assessments
Red Hat
Red Hat rating: Moderate. Red Hat's page for this CVE →
| Product | Status | Plan or fix |
|---|---|---|
| Red Hat OpenShift Container Platform 5 | Affected | No fix yet |
| Red Hat Cost Management On-Premise 1 | Fixed | RHSA-2026:79357 |
| Red Hat Enterprise Linux AppStream (v. 10) | Fixed | RHSA-2026:67463 |
| Red Hat Enterprise Linux AppStream (v. 9) | Fixed | RHSA-2026:67462 |
| Red Hat Enterprise Linux BaseOS (v. 10) | Fixed | RHSA-2026:67463 |
| Red Hat Enterprise Linux BaseOS (v. 9) | Fixed | RHSA-2026:67462 |
| Red Hat OpenShift Container Platform 4.22 | Fixed | RHSA-2026:71446 |
Not affected: 4 products
- Red Hat Enterprise Linux 6
- Red Hat Enterprise Linux 7
- Red Hat Enterprise Linux 8
- Red Hat OpenShift Container Platform 4
Timeline
- 2026-10-02 Threatist record created from CVE-2026-70454
- 2026-10-09 Fix available: RHSA-2026:79357 · Red Hat
- 2026-10-09 Fix available: Red Hat Cost Management On-Premise 1 · Red Hat
- 2026-11-06 Affected versions changed · Red Hat
References
More Samba vulnerabilities
- TI-2020-01431 Netlogon Elevation of Privilege Vulnerability KEVCVSS 3.1CRITICAL 10.0
- TI-2017-05139 Code injection in samba KEVCVSS 3.1CRITICAL 9.8
- TI-2024-11208 Rsync: heap buffer overflow in rsync due to improper checksum length handling CVSS 3.1CRITICAL 9.8
- TI-2015-00210 The Netlogon server implementation in smbd in Samba 3.5.x and 3.6.x before 3.6.25, 4.0.x… CVSS 2.0HIGH 10.0
- TI-2003-00081 Buffer overflow in the SMB/CIFS packet fragment re-assembly code for SMB daemon (smbd) in… CVSS 2.0HIGH 10.0
- TI-2003-00185 Buffer overflow in the call_trans2open function in trans2.c for Samba 2.2.x before… CVSS 2.0HIGH 10.0
Sources
- CVE-2026-70454 · CVE Program
- CVE-2026-70454 · NVD
- FIRST EPSS
- CVE-2026-70454 · Red Hat security data · CC BY 4.0
This product uses the NVD API but is not endorsed or certified by the NVD. Sources and licences