CVE-2026-54700

ConnectBot SSH Client Library is written in Kotlin with Kaitai Struct and KStateMachine. Prior to 0.3.1, the SSH protocol parser trusts attacker-controlled inner byte lengths and element counts without verifying that they fit in the containing packet. A malicious or compromised SSH server can return a small malformed packet whose oversized declarations cause the Kaitai Struct Java runtime to attempt excessive allocation or repeated parsing before detecting truncated input. The general transport path requires a client connection but no authentication or optional feature; malformed SSH-agent messages additionally require SSH agent forwarding. The issue can raise an uncaught OutOfMemoryError and terminate the application process, with no demonstrated confidentiality or integrity impact. This issue is fixed in version 0.3.1.

CVSS

No CVSS.

References

Link	Resource
https://github.com/connectbot/cbssh/commit/a08421fbe7cf8b72fa60fb8b2f98fb465dc43fd9
https://github.com/connectbot/cbssh/pull/194
https://github.com/connectbot/cbssh/releases/tag/v0.3.1
https://github.com/connectbot/cbssh/security/advisories/GHSA-ch3q-cw5r-f4hg

Configurations

No configuration.

History

13 Oct 2026, 16:17

Type	Values Removed	Values Added
New CVE

Information

Published : 2026-10-13 16:17

Updated : 2026-10-16 23:17

NVD link : CVE-2026-54700

Mitre link : CVE-2026-54700

CVE.ORG link : CVE-2026-54700

JSON object : View

Products Affected

No product.

CWE

CWE-20

Improper Input Validation

CWE-789

Memory Allocation with Excessive Size Value

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