Dependency compatibility and limitations¶

xbcloud depends on several system libraries for correct operation. Some versions of these dependencies are known to cause unexpected terminations or unstable behavior and are therefore not supported.

If you are experiencing unexpected terminations or intermittent failures, verify that your environment does not use any of the versions listed below.

libcurl¶

Certain versions of libcurl are known to cause unexpected terminations or connection reuse issues in xbcloud. The following versions are not supported.

Unsupported versions¶

libcurl 7.64.0

Known to mishandle reuse of closed connections
May cause intermittent backup failures in xbcloud

libcurl versions ≥ 8.11.1 and < 8.12.0

Affected by double close of an eventfd file descriptor, CVE-2025-0665
May cause unexpected terminations when xbcloud uses libcurl

Upgrade or downgrade options¶

You should always upgrade xbcloud to the latest version, as it includes fixes for all known issues and compatibility problems.

If the installed libcurl version is not supported, update it depending on the operating system and available repositories.

Recommended - Upgrade to libcurl 8.12.0 or later if these versions are compatible with your operating system.
If upgrading to the latest version ≥ 8.12.0 is not possible, downgrade to a supported version earlier than 8.11.1 to avoid the vulnerability associated with CVE-2025-0665. Ensure that the downgrade is compatible with other system dependencies.

Check the installed libcurl version¶

To check the installed libcurl version, run:

curl --version

Upgrade libcurl - Recommended¶

The following steps show how to update the libcurl to version 8.12.0 on Debian 12. Administrator privileges are necessary for installing packages and configuring system services.

Edit the /etc/apt/sources.list to add the following:

deb http://deb.debian.org/debian bookworm-backports main

Refresh the apt sources:
```
sudo apt update
```

Install the version from bookworm-backports:

sudo apt install -t bookworm-backports libcurl4 curl

Verify the version number:

curl --version

Expected output

curl 8.12.0 (x86_64-pc-linux-gnu) libcurl/8.12.0

Downgrade libcurl¶

The following steps show how to downgrade the libcurl to the default Debian 12 version 7.88.1. Administrator privileges are necessary for installing packages and configuring system services.

Update the package list:
```
sudo apt update
```
Reinstall the default system version of libcurl and curl:
```
sudo apt install --reinstall libcurl4 curl
```

Verify the version number:

curl --version

Expected output

curl 7.88.1 (x86_64-pc-linux-gnu) libcurl/7.88.1 OpenSSL/3.0.9 zlib/1.2.13 libidn2/2.3.4 libssh/0.10.5
Release-Date: 2023-08-02
Protocols: dict file ftp ftps gopher http https imap imaps ldap ldaps mqtt pop3 pop3s rtsp smb smbs smtp smtps telnet tftp 
Features: AsynchDNS IDN IPv6 Largefile NTLM NTLM_WB SSL libz TLS-SRP HTTP2 HSTS HTTPS-proxy Metalink