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Several vulnerabilities have been discovered in the Linux kernel

576 points · 408 comments · luispa

  1. john_strinlai · · focus · HN ↗
    note that _any_ bugfix is assigned a cve, which makes for big numbers.

    >“Due to the layer at which the Linux kernel is in a system, almost any bug might be exploitable to compromise the security of the kernel… Because of this, the CVE assignment team is overly cautious and assign CVE numbers to any bugfix that they identify.”

    <a href="https:&#x2F;&#x2F;docs.kernel.org&#x2F;process&#x2F;cve.html" rel="nofollow">https:&#x2F;&#x2F;docs.kernel.org&#x2F;process&#x2F;cve.html

    &quot;number of cves&quot; is a useless metric, especially when it comes to the kernel.

    1. SAI_Peregrinus · · focus · HN ↗
      Tautologically every bug can legitimately be assigned a CVE, since every bug prevents some feature from working as intended. It&#x27;s therefore a denial of service, which by the definition of the CVE system using CVSS means every bug is at least a 1&#x2F;Low level vulnerability to CVSS v4.0.

      If you&#x27;re willing to stretch, missing but planned features also deny the use of said features since they haven&#x27;t been added yet, and so are CVSS 1&#x2F;Low vulnerabilities.

      Resume-driven development for security researchers has never been easier!

      1. jeroenhd · · focus · HN ↗
        Loads of bugs aren&#x27;t CVE-worthy. If you tell the computer to make a light green but it makes the light red, that&#x27;s a bug but no DoS or other CVE-worthy bug.

        However, the Linux kernel is supposed to run any userland program without crashing, so anything that crashes the kernel is a local DoS and there are a lot of them. It&#x27;s also supposed to shield processes from each other and maintain privilege levels correctly, so many incorrect memory leaks are also CVE worthy. Whether a CVE applies depends on the people and programs using the kernel, and the kernel team can&#x27;t read your code to tell you if it applies or not.

        People reading CVEs wrong (&quot;it&#x27;s got a high number so we must patch within a day&quot;) must be going crazy over this, but the point of CVEs is to let you make judgement calls, not to be a cool statistic about how secure something is.

        Most CVEs are irrelevant to most people, that&#x27;s always been the case.

        1. MyMemoryfails · · focus · HN ↗
          Unless that computer happens be on traffic lights. Will this become CVE? Human life would be at risk.
          1. openasocket · · focus · HN ↗
            I think you have to make a distinction between bugs and actual vulnerabilities. Therac-25 killed people, but I wouldn’t consider anything about it to be a security vulnerability. In my mind, the distinction between a bug and a vulnerability is that a bug is triggered during “normal” operations and can do anything. Whereas a vulnerability requires an adversary to “trigger” the vulnerability, and can do this to achieve some cognizable malicious goal. There’s probably some overlap on the edges; whether an issue in a library is a bug or a vulnerability may depend on how it is used, for example.

            But I think the most important thing to keep in mind is that a bug isn’t necessarily less serious or less important than a vulnerability. A serious bug should be patched just as urgently as a serious vulnerability.

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