CVE-2026-54700: medium-severity vulnerability in connectbot cbssh
ConnectBot SSH: Unbounded SSH field lengths can cause excessive memory allocation
Published · Updated
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13Vexday Risk Score
No sign of exploitation. No public exploitation artifact known so far.
ssvc Trackcvss 6.9epss 0.4%
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:4.0/AV:N/AC:L/AT:N/PR:N/UI:A/VC:N/VI:N/VA:H/SC:N/SI:N/SA:N
Affected products
connectbot · cbsshRelated CVEs — connectbot cbssh
In the same product, most dangerous first.