Subject: Re: bug#40142: CVE checker return false positives

From: Ludovic Courtès <[email-masked]>
Date: Sat, 21 Mar 2020 17:25:23 +0100

Hi,

Brice Waegeneire <[email-masked]> skribis:

> The CVE checker of “guix lint” returns false positives:
> ┌────
> │ LANGUAGE=C guix lint git 2>&1
> ├───
> │ gnu/packages/version-control.scm:149:2: [email-masked]: probably
> vulnerable to CVE-2020-2136, CVE-2019-1003010, CVE-2018-1000110,
> CVE-2018-1000182

[...]

> • [CVE-2020-2136]: “Jenkins Git Plugin 4.2.0 and earlier […]”
> • [CVE-2019-1003010]: “[…] Jenkins Git Plugin 3.9.1 and earlier […]”
> • [CVE-2018-1000110]: “[…] Jenkins Git Plugin version 3.7.0 and earlier
>   […]”
> • [CVE-2018-1000182]: “[…] Jenkins Git Plugin 3.9.0 and older […]”

(guix cve) reports it as applying to “git”:

--8<---------------cut here---------------start------------->8---
scheme@(guix cve)> (define items
		     (call-with-decompressed-port 'gzip (http-fetch (yearly-feed-uri 2020))
		       json->cve-items))
scheme@(guix cve)> (find (lambda (item)
			   (string=? (cve-id (cve-item-cve item)) "CVE-2020-2136"))
			 items)
$130 = #<<cve-item> cve: #<<cve> id: "CVE-2020-2136" data-type: CVE data-format: MITRE references: (#<<cve-reference> url: "http://www.openwall.com/lists/oss-security/2020/03/09/1" tags: ("Third Party Advisory")> #<<cve-reference> url: "https://jenkins.io/security/advisory/2020-03-09/#SECURITY-1723" tags: ("Vendor Advisory")>)> configurations: (("git" (<= "4.2.0"))) published-date: #<date nanosecond: 0 second: 0 minute: 15 hour: 16 day: 9 month: 3 year: 2020 zone-offset: 0> last-modified-date: #<date nanosecond: 0 second: 0 minute: 4 hour: 20 day: 9 month: 3 year: 2020 zone-offset: 0>>
--8<---------------cut here---------------end--------------->8---

I think the problem stems from the fact that the CVE configuration
specify “jenkins:git” (where “jenkins” is the “vendor” and “git” is the
“product”), but we just strip the vendor part:

--8<---------------cut here---------------start------------->8---
$ wget -O - -q https://nvd.nist.gov/feeds/json/cve/1.1/nvdcve-1.1-2020.json.gz| gunzip | jq

[…]

      "configurations": {
        "CVE_data_version": "4.0",
        "nodes": [
          {
            "operator": "OR",
            "cpe_match": [
              {
                "vulnerable": true,
                "cpe23Uri": "cpe:2.3:a:jenkins:git:*:*:*:*:*:jenkins:*:*",
                "versionEndIncluding": "4.2.0"
              }
            ]
          }
        ]
--8<---------------cut here---------------end--------------->8---

It’s usually the case that the vendor part has little relevance for free
software packages, but in this case it does make a difference.

Probably the fix would be to preserve the vendor part in the API and to
somehow use it meaningfully.

Ideas & patches welcome!

> Also note the missing / on the first line and it output on `stderr'
> instead of `stdout'.

What do you mean?

Thanks,
Ludo’.