CVE-2018-10933
Description
A vulnerability was found in libssh's server-side state machine. A malicious client could create channels without first performing authentication, resulting in unauthorized access.
Statement
This vulnerability affects libssh shipped in Red Hat Enterprise Linux 7 Extras. No libssh packages are included in Red Hat Enterprise Linux 6 and earlier. This issue does not affect libssh2 or openssh.
This issue can only be affect applications that use libssh to implement an SSH server; SSH client functionality is not affected. No packages in Red Hat products use libssh to implement an SSH server. Therefore, no package from Red Hat that uses the libssh library is affected by this flaw.
The libssh library is available for customer or third party code to use. Such code that is linked against libssh and uses the ssh_bind* functions may be affected by this flaw.
Common Vulnerability Scoring System (CVSS) Score Details
Info alert:Important note
CVSS scores for open source components depend on vendor-specific factors (e.g. version or build chain). Therefore, Red Hat's score and impact rating can be different from NVD and other vendors. Red Hat remains the authoritative CVE Naming Authority (CNA) source for its products and services (see Red Hat classifications).
CVSS v3 Score Breakdown
| Red Hat | NVD | cve.org | |
|---|---|---|---|
| Base Score | 9.1 | 9.1 | 9.1 |
| Attack Vector | Network | Network | Network |
| Attack Complexity | Low | Low | Low |
| Privileges Required | None | None | None |
| User Interaction | None | None | None |
| Scope | Unchanged | Unchanged | Unchanged |
| Confidentiality | High | High | High |
| Integrity Impact | High | High | High |
| Availability Impact | None | None | None |
Vector
Red Hat: CVSS:3.0/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:H/A:N
NVD: CVSS:3.0/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:H/A:N
cve.org: CVSS:3.0/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:H/A:N
Understanding the Weakness (CWE)
Integrity,Confidentiality,Availability,Access Control
Technical Impact: Read Application Data; Gain Privileges or Assume Identity; Execute Unauthorized Code or Commands
This weakness can lead to the exposure of resources or functionality to unintended actors, possibly providing attackers with sensitive information or even execute arbitrary code.
Acknowledgements
Red Hat would like to thank the libssh team for reporting this issue. Upstream acknowledges Peter Winter-Smith (NCC Group) as the original reporter.
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