BREW-PSUTILS-CVE-2026-31826 (GHSA-HQMH-PPP3-XVM7)

Vulnerability from osv_homebrew – Published: 2026-08-13 17:29 – Updated: 2026-09-22 00:44 – Source website
VLAI
Summary
pypdf: manipulated stream length values can exhaust RAM
Details

Impact

An attacker who uses this vulnerability can craft a PDF which leads to large memory usage. This requires parsing a content stream with a rather large /Length value, regardless of the actual data length inside the stream.

Patches

This has been fixed in pypdf==6.8.0.

Workarounds

If you cannot upgrade yet, consider applying the changes from PR #3675.

As far as we are aware, this mostly affects reading from buffers of unknown size, as returned by open("file.pdf", mode="rb") for example. Passing a file path or a BytesIO buffer to pypdf instead does not seem to trigger the vulnerability.

Severity
6.8 (Medium)
CVSS:4.0/AV:L/AC:L/AT:N/PR:N/UI:P/VC:N/VI:N/VA:H/SC:N/SI:N/SA:N
References
To clipboard 

{
  "affected": [
    {
      "ecosystem_specific": {
        "fix": "bump",
        "range_state": "fixed",
        "resource": "pypdf",
        "resource_purl": "pkg:pypi/pypdf@6.17.0",
        "upstream_fixed_in": "6.8.0"
      },
      "package": {
        "ecosystem": "Homebrew",
        "name": "psutils",
        "purl": "pkg:brew/psutils"
      },
      "ranges": [
        {
          "events": [
            {
              "introduced": "3.0"
            },
            {
              "fixed": "3.3.14_9"
            }
          ],
          "type": "ECOSYSTEM"
        }
      ]
    }
  ],
  "database_specific": {
    "confidence": "high",
    "source": "matched",
    "strategy": "registry",
    "upstream_evidence": [
      {
        "ecosystem": "PyPI",
        "key": "pkg:pypi/pypdf@6.17.0",
        "name": "pypdf",
        "resource": "pypdf",
        "strategy": "registry",
        "subject_version": "6.17.0"
      }
    ]
  },
  "details": "### Impact\n\nAn attacker who uses this vulnerability can craft a PDF which leads to large memory usage. This requires parsing a content stream with a rather large `/Length` value, regardless of the actual data length inside the stream.\n\n### Patches\nThis has been fixed in [pypdf==6.8.0](https://github.com/py-pdf/pypdf/releases/tag/6.8.0).\n\n### Workarounds\nIf you cannot upgrade yet, consider applying the changes from PR [#3675](https://github.com/py-pdf/pypdf/pull/3675).\n\nAs far as we are aware, this mostly affects reading from buffers of unknown size, as returned by `open(\"file.pdf\", mode=\"rb\")` for example. Passing a file path or a `BytesIO` buffer to *pypdf* instead does not seem to trigger the vulnerability.",
  "id": "BREW-psutils-CVE-2026-31826",
  "modified": "2026-09-22T00:44:13Z",
  "published": "2026-08-13T17:29:24Z",
  "references": [
    {
      "type": "WEB",
      "url": "https://github.com/py-pdf/pypdf/security/advisories/GHSA-hqmh-ppp3-xvm7"
    },
    {
      "type": "ADVISORY",
      "url": "https://nvd.nist.gov/vuln/detail/CVE-2026-31826"
    },
    {
      "type": "WEB",
      "url": "https://github.com/py-pdf/pypdf/pull/3675"
    },
    {
      "type": "WEB",
      "url": "https://github.com/py-pdf/pypdf/commit/3c550b3196adeba1506a26e57c09c09fac75e9aa"
    },
    {
      "type": "PACKAGE",
      "url": "https://github.com/py-pdf/pypdf"
    },
    {
      "type": "WEB",
      "url": "https://github.com/py-pdf/pypdf/releases/tag/6.8.0"
    }
  ],
  "schema_version": "1.7.3",
  "severity": [
    {
      "score": "CVSS:4.0/AV:L/AC:L/AT:N/PR:N/UI:P/VC:N/VI:N/VA:H/SC:N/SI:N/SA:N",
      "type": "CVSS_V4"
    }
  ],
  "summary": "pypdf: manipulated stream length values can exhaust RAM",
  "upstream": [
    "GHSA-hqmh-ppp3-xvm7",
    "CVE-2026-31826",
    "PYSEC-2026-3019"
  ]
}



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