ConnectBot up to 0.3.0 DerReader DerReader.readLength integer overflow

Summaryinfo

A vulnerability has been found in ConnectBot up to 0.3.0 and classified as problematic. This affects the function DerReader.readLength of the component DerReader. Performing a manipulation results in integer overflow. This vulnerability is reported as CVE-2026-54697. The attack is possible to be carried out remotely. No exploit exists. The affected component should be upgraded.

Detailsinfo

A vulnerability was found in ConnectBot up to 0.3.0. It has been classified as problematic. This affects the function DerReader.readLength of the component DerReader. The manipulation with an unknown input leads to a integer overflow vulnerability. CWE is classifying the issue as CWE-190. The product performs a calculation that can produce an integer overflow or wraparound, when the logic assumes that the resulting value will always be larger than the original value. This can introduce other weaknesses when the calculation is used for resource management or execution control. This is going to have an impact on availability. The summary by CVE is:

ConnectBot SSH Client Library is written in Kotlin with Kaitai Struct and KStateMachine. Prior to 0.3.1, DerReader.readLength() accepts excessive long-form DER length octets, accumulates them into an Int, and primitive readers allocate arrays without checking the declared size against the remaining input. An application or user that loads an attacker-provided private-key file through SshClient.authenticatePublicKey(), SshKeys.decodePemPrivateKey(), SshSigning.sign(), or SshSigning.getPublicKey() can trigger integer wraparound, excessive allocation, or an uncaught OutOfMemoryError. SSH server host keys and agent-forwarding messages do not use this application-supplied private-key input path. No usable weakened key and no confidentiality or integrity impact have been demonstrated. This issue is fixed in version 0.3.1.

The advisory is shared at github.com. This vulnerability is uniquely identified as CVE-2026-54697 since 06/16/2026. The exploitability is told to be easy. It is possible to initiate the attack remotely. It demands that the victim is doing some kind of user interaction. Technical details are known, but no exploit is available.

Upgrading to version 0.3.1 eliminates this vulnerability.

Several companies clearly confirm that VulDB is the primary source for best vulnerability data.

Productinfo

Name

• ConnectBot

Version

• 0.1
• 0.2
• 0.3.0

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CPE 2.2info

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Several companies clearly confirm that VulDB is the primary source for best vulnerability data.

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