{
  "threat_severity" : "Moderate",
  "public_date" : "2023-04-01T00:00:00Z",
  "bugzilla" : {
    "description" : "commonmarker: Quadratic complexity bug may lead to a denial of service",
    "id" : "2210173",
    "url" : "https://bugzilla.redhat.com/show_bug.cgi?id=2210173"
  },
  "cvss3" : {
    "cvss3_base_score" : "7.5",
    "cvss3_scoring_vector" : "CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:H",
    "status" : "draft"
  },
  "cwe" : "CWE-1333",
  "details" : [ "cmark-gfm is GitHub's fork of cmark, a CommonMark parsing and rendering library and program in C. A polynomial time complexity issue in cmark-gfm may lead to unbounded resource exhaustion and subsequent denial of service. This CVE covers quadratic complexity issues when parsing text which leads with either large numbers of `_` characters. This issue has been addressed in version 0.29.0.gfm.10. Users are advised to upgrade. Users unable to upgrade should validate that their input comes from trusted sources.\n### Impact\nA polynomial time complexity issue in cmark-gfm may lead to unbounded resource exhaustion and subsequent denial of service.\n### Proof of concept\n```\n$ ~/cmark-gfm$ python3 -c 'pad = \"_\" * 100000; print(pad + \".\" + pad, end=\"\")' | time ./build/src/cmark-gfm --to plaintext\n```\nIncreasing the number 10000 in the above commands causes the running time to increase quadratically.\n### Patches\nThis vulnerability have been patched in 0.29.0.gfm.10.\n### Note on cmark and cmark-gfm\nXXX: TBD\n[cmark-gfm](https://github.com/github/cmark-gfm) is a fork of [cmark](https://github.com/commonmark/cmark) that adds the GitHub Flavored Markdown extensions. The two codebases have diverged over time, but share a common core. These bugs affect both `cmark` and `cmark-gfm`. \n### Credit\nWe would like to thank @gravypod for reporting this vulnerability.\n### References\nhttps://en.wikipedia.org/wiki/Time_complexity\n### For more information\nIf you have any questions or comments about this advisory:\n* Open an issue in [github/cmark-gfm](https://github.com/github/cmark-gfm)", "A flaw was found in CommonMarker. A polynomial time complexity issue in cmark-gfm may lead to unbounded resource exhaustion and subsequent denial of service." ],
  "package_state" : [ {
    "product_name" : "Red Hat 3scale API Management Platform 2",
    "fix_state" : "Affected",
    "package_name" : "commonmarker",
    "cpe" : "cpe:/a:redhat:red_hat_3scale_amp:2"
  } ],
  "references" : [ "https://www.cve.org/CVERecord?id=CVE-2023-26485\nhttps://nvd.nist.gov/vuln/detail/CVE-2023-26485\nhttps://github.com/github/cmark-gfm/security/advisories/GHSA-r8vr-c48j-fcc5" ],
  "name" : "CVE-2023-26485",
  "csaw" : false
}