ghsa-hm9v-vj3r-r55m
Vulnerability from github
Impact
An attacker who uses this vulnerability can craft a PDF which leads to an infinite loop. This infinite loop blocks the current process and can utilize a single core of the CPU by 100%. It does not affect memory usage. That is, for example, the case if the user extracted metadata from such a malformed PDF.
Patches
The issue was fixed with https://github.com/py-pdf/pypdf/pull/1331
Workarounds
If you cannot update your version of PyPDF2 (preferably to pypdf>3.1.0 as PyPDF2 is deprecated), you should modify PyPDF2/generic/_data_structures.py::read_object.
Replace:
python
else:
# number object OR indirect reference
peek = stream.read(20)
stream.seek(-len(peek), 1) # reset to start
if IndirectPattern.match(peek) is not None:
return IndirectObject.read_from_stream(stream, pdf)
else:
return NumberObject.read_from_stream(stream)
by
python
elif tok in b"0123456789+-.":
# number object OR indirect reference
peek = stream.read(20)
stream.seek(-len(peek), 1) # reset to start
if IndirectPattern.match(peek) is not None:
return IndirectObject.read_from_stream(stream, pdf)
else:
return NumberObject.read_from_stream(stream)
else:
raise PdfReadError(
f"Invalid Elementary Object starting with {tok} @{stream.tell()}"
)
References
{
"affected": [
{
"package": {
"ecosystem": "PyPI",
"name": "PyPDF2"
},
"ranges": [
{
"events": [
{
"introduced": "2.10.5"
},
{
"fixed": "2.10.6"
}
],
"type": "ECOSYSTEM"
}
],
"versions": [
"2.10.5"
]
}
],
"aliases": [
"CVE-2023-36807"
],
"database_specific": {
"cwe_ids": [
"CWE-835"
],
"github_reviewed": true,
"github_reviewed_at": "2023-06-30T22:19:39Z",
"nvd_published_at": "2023-06-30T19:15:09Z",
"severity": "MODERATE"
},
"details": "### Impact\nAn attacker who uses this vulnerability can craft a PDF which leads to an infinite loop.\nThis infinite loop blocks the current process and can utilize a single core of the CPU by 100%. It does not affect memory usage. That is, for example, the case if the user extracted metadata from such a malformed PDF.\n\n### Patches\nThe issue was fixed with https://github.com/py-pdf/pypdf/pull/1331\n\n### Workarounds\nIf you cannot update your version of `PyPDF2` (preferably to `pypdf\u003e3.1.0` as PyPDF2 is deprecated), you should modify `PyPDF2/generic/_data_structures.py::read_object`.\n\nReplace:\n\n```python\n else:\n # number object OR indirect reference\n peek = stream.read(20)\n stream.seek(-len(peek), 1) # reset to start\n if IndirectPattern.match(peek) is not None:\n return IndirectObject.read_from_stream(stream, pdf)\n else:\n return NumberObject.read_from_stream(stream)\n```\n\nby\n\n```python\n elif tok in b\"0123456789+-.\":\n # number object OR indirect reference\n peek = stream.read(20)\n stream.seek(-len(peek), 1) # reset to start\n if IndirectPattern.match(peek) is not None:\n return IndirectObject.read_from_stream(stream, pdf)\n else:\n return NumberObject.read_from_stream(stream)\n else:\n raise PdfReadError(\n f\"Invalid Elementary Object starting with {tok} @{stream.tell()}\"\n )\n```\n\n### References\n* [pypdf issue #1329](https://github.com/py-pdf/pypdf/issues/1329)\n* [pypdf PR #1331](https://github.com/py-pdf/pypdf/pull/1331)",
"id": "GHSA-hm9v-vj3r-r55m",
"modified": "2023-06-30T22:19:39Z",
"published": "2023-06-30T22:19:39Z",
"references": [
{
"type": "WEB",
"url": "https://github.com/py-pdf/pypdf/security/advisories/GHSA-hm9v-vj3r-r55m"
},
{
"type": "ADVISORY",
"url": "https://nvd.nist.gov/vuln/detail/CVE-2023-36807"
},
{
"type": "WEB",
"url": "https://github.com/py-pdf/pypdf/issues/1329"
},
{
"type": "WEB",
"url": "https://github.com/py-pdf/pypdf/pull/1331"
},
{
"type": "WEB",
"url": "https://github.com/py-pdf/pypdf/commit/e6531a25325e7e0174b6a1ba03b57320b5227f6b"
},
{
"type": "PACKAGE",
"url": "https://github.com/py-pdf/pypdf"
}
],
"schema_version": "1.4.0",
"severity": [
{
"score": "CVSS:3.1/AV:L/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:H",
"type": "CVSS_V3"
}
],
"summary": "PyPDF2 vulnerable to possible Infinite Loop when reading malformed objects"
}
Sightings
| Author | Source | Type | Date |
|---|
Nomenclature
- Seen: The vulnerability was mentioned, discussed, or seen somewhere by the user.
- Confirmed: The vulnerability is confirmed from an analyst perspective.
- Exploited: This vulnerability was exploited and seen by the user reporting the sighting.
- Patched: This vulnerability was successfully patched by the user reporting the sighting.
- Not exploited: This vulnerability was not exploited or seen by the user reporting the sighting.
- Not confirmed: The user expresses doubt about the veracity of the vulnerability.
- Not patched: This vulnerability was not successfully patched by the user reporting the sighting.