Picolibc in Zephyr firmware: identifiers and CRA notes

What it is

Picolibc

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Notes on this component

Picolibc, the C standard library this build links in, built from the west module (CONFIG_PICOLIBC_USE_MODULE). When modules-deps.spdx already lists the picolibc module this row adds nothing; when it does not, the version is left blank rather than borrowed from the Zephyr kernel. Picolibc carries code copied from newlib; see the Picolibc module row for the newlib advisories that may apply.

Where it hides in a firmware SBOM

It is compiled into the kernel image when CONFIG_PICOLIBC_USE_MODULE is y. It does not appear in west spdx output; the only trace is the .config file in your build directory.

The identifiers we assign

PURLpackage URL: a standard way to name a software package

pkg:github/picolibc/picolibc@{version}

{version} is filled in from your build. The version is read from the version your SBOM already carries for it.

The SBOM check adds these identifiers to a component your build listed without them.

Honest gaps

Vendor: picolibc.

This row has no CPE.

Where this row comes from

https://github.com/zephyrproject-rtos/zephyr/blob/413b789deb391d3a37d06b463288a5fe765ee57e/lib/libc/picolibc/Kconfig
Checked on 14 October 2026.

Known vulnerabilities

Not checked yet

Vulnerability data changes daily. Check the version you ship in the SBOM check.

CRA notes

• List this component in your SBOM. Annex I, Part II (1): Identify and document components and vulnerabilities, including an SBOMKnow what is in your product. Identify and document its components and their vulnerabilities, including by producing a software bill of materials (SBOM) in a common machine-readable format that covers at least the top-level dependencies.
• Ship the version with no known exploitable vulnerabilities at release. Annex I, Part I (2(a)): Made available without known exploitable vulnerabilitiesWhen you place a release on the market, it must not ship with known vulnerabilities that can be exploited in your product. "Exploitable" means an attacker could effectively use it under practical operating conditions (Article 3(41)), not only in theory or in a lab. The Commission's draft guidance (C(2026) 5252, points 231 to 237; a draft, not binding) gives three ways a vulnerability is "known". One: it is listed in a relevant public vulnerability database, such as the European vulnerability database (EUVD) or another prominent one. Two: you learned of it from information that is not public, for example a security researcher's coordinated disclosure or your own testing and analysis; a vulnerability you know about and have not disclosed still counts. Three: it has been publicly and prominently reported in reliable media, whether specialist security publications or general news. A report is not yet proof: it does not by itself mean the vulnerability can be exploited in practice or applies to your product, so investigate promptly and confirm whether it does. A limited time may pass between the first report and that confirmation. If a vulnerability becomes known shortly before release, you decide from your cybersecurity risk assessment whether the release can go out or the vulnerability must be fixed first. Weigh its severity, exploitability and potential impact, and the risks to the product once in use; you may also weigh the risks of delaying the release, for example because it fixes other exploitable vulnerabilities. After release, the Part II vulnerability handling requirements still apply. Check your components against vulnerability databases before each release, and fix or justify what you find.

Source: Annex I of Regulation (EU) 2024/2847 (Cyber Resilience Act), legal state 2026.10.13-1.

Related Zephyr components

No related components yet.

Guides that mention Picolibc

• The CRA for Zephyr developers: what the law asks, what west spdx gives you, and what is left

Next step

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