CVE-2026-48095

{
  "id": "CVE-2026-48095",
  "cveTags": [],
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              "automatable": "no"
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              "technicalImpact": "total"
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          "version": "2.0.3",
          "timestamp": "2026-06-08T19:10:27.520353Z"
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          "scope": "UNCHANGED",
          "version": "3.1",
          "baseScore": 8.8,
          "attackVector": "NETWORK",
          "baseSeverity": "HIGH",
          "vectorString": "CVSS:3.1/AV:N/AC:L/PR:N/UI:R/S:U/C:H/I:H/A:H",
          "integrityImpact": "HIGH",
          "userInteraction": "REQUIRED",
          "attackComplexity": "LOW",
          "availabilityImpact": "HIGH",
          "privilegesRequired": "NONE",
          "confidentialityImpact": "HIGH"
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  "affected": [
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      "source": "security-advisories@github.com",
      "affectedData": [
        {
          "vendor": "mcmilk",
          "product": "7-Zip",
          "versions": [
            {
              "status": "affected",
              "version": "<= 26.00"
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          ]
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  "published": "2026-06-05T15:16:53.520",
  "references": [
    {
      "url": "https://securitylab.github.com/advisories/GHSL-2026-140_7-Zip/",
      "tags": [
        "Exploit",
        "Third Party Advisory"
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    {
      "url": "https://sourceforge.net/p/sevenzip/discussion/45797/thread/555e132ba4",
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        "Product",
        "Release Notes"
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      "source": "security-advisories@github.com"
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    {
      "url": "https://securitylab.github.com/advisories/GHSL-2026-140_7-Zip/",
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      "source": "134c704f-9b21-4f2e-91b3-4a467353bcc0"
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  "vulnStatus": "Modified",
  "weaknesses": [
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      "type": "Secondary",
      "source": "security-advisories@github.com",
      "description": [
        {
          "lang": "en",
          "value": "CWE-190"
        },
        {
          "lang": "en",
          "value": "CWE-787"
        }
      ]
    }
  ],
  "descriptions": [
    {
      "lang": "en",
      "value": "7-Zip is a file archiver with a high compression ratio. Versions 26.00 and prior contain a heap buffer overflow vulnerability caused by an under-allocation in the NTFS compressed stream buffer (GetCuSize shift UB), potentially allowing attackers to cause arbitrary code execution or application crashes. CInStream::GetCuSize() in the NTFS handler computes the compression-unit buffer size as (UInt32)1 << (BlockSizeLog + CompressionUnit), and a crafted image with ClusterSizeLog >= 28 and CompressionUnit == 4 drives the exponent to 32, which is undefined behavior and collapses on x86/x64 so _inBuf is allocated as 1 byte. ReadStream_FALSE then writes up to 256 MB of attacker-controlled data into that 1-byte buffer in 64 KB iterations, and because the CInStream object sits only 304 bytes after _inBuf, its vtable pointer is overwritten and the next dispatched call achieves a vtable hijack. On 32-bit builds the overflow is unconditionally reached; on 64-bit it requires the parallel 8 GB _outBuf allocation to succeed, otherwise failing closed to denial of service. The NTFS handler is enabled by default in stock 7z.dll and, via signature-based fallback matching \"NTFS    \" at offset 3, will open a crafted image regardless of file extension during extraction or testing. Version 26.01 fixes the issue."
    }
  ],
  "lastModified": "2026-06-17T10:54:50.997",
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