Vulnerability · Published Aug 14, 2026 · Assigned by GitHub_M
CVE-2026-47192kas's late signature validation may allow unnoticed repository manipulations
Low 2.1
In plain English
A low-severity security flaw in kas from siemens. There are no confirmed reports of exploitation so far. The chance it is exploited in the next 30 days is estimated at 0.3% (higher than 17% of all known vulnerabilities). Fixed versions are available - upgrade the affected package.
Official description
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.
Affected packages & fixed versions
| Ecosystem | Package | Fixed in | Advisory |
|---|---|---|---|
| Debian:13 | kas | no fix listed | DEBIAN-CVE-2026-47192 |
| Debian:14 | kas | 5.3-1 | DEBIAN-CVE-2026-47192 |
| PyPI | kas | 5.3 | GHSA-4vqc-wpwg-vh7j |
| PyPI | kas | 5.3 | PYSEC-2026-2543 |
| Ubuntu:22.04:LTS | kas | no fix listed | UBUNTU-CVE-2026-47192 |
| Ubuntu:24.04:LTS | kas | no fix listed | UBUNTU-CVE-2026-47192 |
| Ubuntu:25.10 | kas | no fix listed | UBUNTU-CVE-2026-47192 |
| Ubuntu:26.04:LTS | kas | no fix listed | UBUNTU-CVE-2026-47192 |
| Ubuntu:26.10 | kas | no fix listed | UBUNTU-CVE-2026-47192 |
Affected products (as reported)
Weakness: CWE-347 · Vector: CVSS:4.0/AV:N/AC:H/AT:P/PR:L/UI:P/VC:L/VI:L/VA:L/SC:N/SI:N/SA:N
References
- https://github.com/siemens/kas/security/advisories/GHSA-4vqc-wpwg-vh7j x_refsource_CONFIRM
- https://github.com/siemens/kas/security/advisories/GHSA-qjwp-hrq6-r26r x_refsource_MISC
- https://github.com/siemens/kas/commit/4cb4a3d01122ffaec9feaae768a5814092f6f9b5 x_refsource_MISC
- https://github.com/siemens/kas/commit/5b2114becfc154b16ef496d24f8c2191a2297f57 x_refsource_MISC
- https://github.com/pypa/advisory-database/tree/main/vulns/kas/PYSEC-2026-2543.yaml x_refsource_MISC