CVE-2026-47192
LowCVSS 2.1Exploitation Probability (EPSS)
Low risk6th percentile - higher than 6% of all known CVEs
Summary
kas is a setup tool for bitbake based projects. In versions from 4.8 to before 5.3, kas checks out and processes repositories and configuration includes prior to validating signatures of those repositories. Under very specific conditions, this may allow an attacker to replace the original repository with one under their control.
Risk Assessment
The risk is the potential replacement of the repository and validation key, which could lead to injection of malicious code into the build process. The attack requires many conditions, but if met, it can compromise the integrity of the entire project.
Recommendation
Upgrade to kas version 5.3 or later, which includes fixes. As a workaround, pin the expected signature key via its fingerprint, even when storing it as a file in a repository.
Other vulnerabilities in kas
See all- CVE-2026-54548Low
kas, a setup tool for bitbake based projects, prior to 5.4, internal SSH key setup triggered by SSH_PRIVATE_KEY or SSH_PRIVATE_KEY_FILE creates ~/.ssh/config when no user-specific SSH configuration exists and adds a global Host * rule containing StrictHostKeyChecking no. In kas/libcmds.py, ssh_no_host_key_check() runs without checking ctx.managed_env, so the setting persists after kas exits and affects future SSH sessions by the same local user, extending beyond the intended short-lived continuous integration environment. A later SSH connection can therefore accept an attacker-controlled host key without verification, increasing the risk of a man-in-the-middle attack that compromises session confidentiality or integrity.
- CVE-2026-47191Low
kas is a setup tool for bitbake based projects. Prior to version 5.3, when relying solely on a git commit ID (SHA-1 or SHA-256) to verify repository integrity, users may be tricked into checking out a branch of the same name from a compromised repository. This primarily affects SHA-256 commit IDs, as SHA-1 may be vulnerable to hash collisions.
Original NVD description (English source)
kas is a setup tool for bitbake based projects. Starting in version 4.8 and prior to version 5.3, kas checks out and processes repositories regarding configuration includes prior to validating signatures of those repositories. This may allow to replace on original repository with one under the control of an attacker under very specific conditions. First of all, the attacker must have gained control of a repository that a kas file of the victim is referencing. Furthermore, the following conditions must be fulfilled: the victim's kas configuration must include a configuration file from the attacked repository; the repository state is referenced by tag, and no commit ID is specified (this is triggering a warning, though); the key used for validating the tag or commit signature is stored as file in a repository; no fingerprint for the key is specified; and the `_source_dir` key must not be set by the victim when calling kas (e.g. by avoiding a local `.config.yaml`). Given these conditions, the attacker could modify the included kas configuration in way that the key used to validate the tag signature of the attacker's repository could be replaced by an attacker-chosen key. No other exploit possibilities have been identified so far, but this does not rule out that those may exist. All patches have been released along with kas version 5.3. As a workaround, pin the expected signature key via its fingerprint, also when storing it as file in a repository.
Vulnerability data from NVD (NIST) · CISA KEV · EPSS