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CVE-2026-88265 (GCVE-0-2026-88265)

Vulnerability from cvelistv5 – Published: 2026-09-10 08:57 – Updated: 2026-09-10 08:57
VLAI
Title
Crun: crun: /dev/null symlink follow during stdio reopen allows host bind-mount write and chown
Summary
A flaw was found in crun. After pivot_root, reopening /dev/null for stdio can follow a symlink and attach a host file to container stdio, then change that file's ownership. Affected versions are crun 1.29.1 and earlier. Default configurations that mount a fresh /dev are not exposed. No fixed release is available yet.
CWE
  • CWE-59 - Improper Link Resolution Before File Access ('Link Following')
References
Impacted products
Vendor Product Version CPE status
Red Hat Red Hat Hardened Images     cpe:/a:redhat:hummingbird:1
Create a notification for this product.
Date Public
2026-09-09 00:00
Show details on NVD website

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          "time": "2026-09-09T00:00:00.000Z",
          "value": "Made public."
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      "workarounds": [
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    "datePublished": "2026-09-10T08:57:03.229Z",
    "dateReserved": "2026-09-10T01:57:19.212Z",
    "dateUpdated": "2026-09-10T08:57:03.229Z",
    "state": "PUBLISHED"
  },
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    "redhat_vex": {
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      "cve": "CVE-2026-88265",
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      "product_status:known_affected": "1",
      "source": "Red Hat CSAF VEX",
      "status": "final",
      "title": "crun: crun: /dev/null symlink follow during stdio reopen allows host bind-mount write and chown",
      "url": "https://security.access.redhat.com/data/csaf/v2/vex/2026/cve-2026-88265.json",
      "version": "3"
    }
  }
}



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