# CVE-2026-47192: kas's late signature validation may allow unnoticed repository manipulations

> Attackers can bypass signature validation in kas to inject malicious configurations, potentially leading to code execution if specific repository and key conditions are met.

- **Severity:** Low 2.1 (`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`)
- **Exploited in the wild:** Not known
- **Login needed:** Any signed-in user
- **Attackable:** Over the internet
- **Victim action needed:** A user has to click or open something
- **Fix available:** Yes
- **Published:** 14 Aug 2026
- **Updated:** 14 Aug 2026
- **Also known as:** DEBIAN-CVE-2026-47192, GHSA-4vqc-wpwg-vh7j, PYSEC-2026-2543, UBUNTU-CVE-2026-47192

## What is CVE-2026-47192?

CVE-2026-47192 is a low-severity vulnerability in siemens kas, published on 14 Aug 2026. Any signed-in user can exploit it over the network, and only if a user opens a file or follows a link.

### 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.

Weakness: CWE-347 (Improper Verification of Cryptographic Signature)

## Which versions are affected by CVE-2026-47192?

3 open source packages ship an affected version, including kas.


| Package | Ecosystem | Affected | Fixed in |
| --- | --- | --- | --- |
| `kas` | PyPI | From 4.8 | 5.3 |
| `kas` | PyPI | From 4.8 | 5.3 |
| `kas` | PyPI | From 4.8 | 5.3 |

## How do I fix CVE-2026-47192?

Upgrade kas to 5.3 or later.

## Is CVE-2026-47192 being exploited?

There is no known exploitation of CVE-2026-47192 in the wild and no public exploit code.

## Fix prompt for AI coding agents

```text
Check this codebase for CVE-2026-47192 and fix it if it is affected.

What it is: CVE-2026-47192 is a low-severity vulnerability in siemens kas, published on 14 Aug 2026. Any signed-in user can exploit it over the network, and only if a user opens a file or follows a link.
Exploitation: There is no known exploitation of CVE-2026-47192 in the wild and no public exploit code.

Affected packages and fixed versions:
- kas (PyPI): affected from 4.8; fixed in 5.3
- kas (PyPI): affected from 4.8; fixed in 5.3
- kas (PyPI): affected from 4.8; fixed in 5.3

Task:
1. Search the dependency manifests and lockfiles (for example package.json, package-lock.json, requirements.txt, poetry.lock, uv.lock, pom.xml, build.gradle, go.mod, Cargo.lock, Gemfile.lock) and any Dockerfiles for the affected packages, including transitive dependencies.
2. If an affected version is in use, upgrade it to the fixed version for its release line with the project's package manager, so the lockfile is regenerated. Prefer the smallest upgrade that fixes it.
3. If there is no fix, or the upgrade would break the build, do not guess: explain the risk and the safest workaround instead.
4. Run the tests and summarise what changed and why.
5. If nothing in the project is affected, say so and change nothing.

Reference: https://insights.sbomify.com/CVE-2026-47192/ (Markdown: https://insights.sbomify.com/CVE-2026-47192/index.md)
```

## Sources

- CVE record: https://www.cve.org/CVERecord?id=CVE-2026-47192
- NVD: https://nvd.nist.gov/vuln/detail/CVE-2026-47192
- OSV: https://osv.dev/vulnerability/CVE-2026-47192

---
From sbomify Insights: https://insights.sbomify.com/CVE-2026-47192/
Summaries are generated and may contain mistakes; the official description above is the record.