Medium
pypdf: Possible infinite loop during recovery attempts in DictionaryObject.read_from_stream
Type: advisorySources: OSV
pypdf is a free and open-source pure-python PDF library. Versions prior to 6.9.2 have a vulnerability in which an attacker can craft a PDF which leads to an infinite loop. This requires reading a file in non-strict mode. This has been fixed in pypdf 6.9.2. If users cannot upgrade yet, consider applying the changes from the patch manually.
- Products
- Not specified
- Affected versions
- Not specified
- Fixed versions
- Not specified
- CVEs
- CVE-2026-33699
- Confirmed fixed CVEs
- Not specified
- Updated in this feed
- 2 Nov 2026, 22:11 UTC · Revision 1
Source evidence
pypdf: Possible infinite loop during recovery attempts in DictionaryObject.read_from_stream
core-osv · Original sourcePublished 26 Mar 2026, 23:58 UTC
pypdf is a free and open-source pure-python PDF library. Versions prior to 6.9.2 have a vulnerability in which an attacker can craft a PDF which leads to an infinite loop. This requires reading a file in non-strict mode. This has been fixed in pypdf 6.9.2. If users cannot upgrade yet, consider applying the changes from the patch manually.
osv:CVE-2026-33699
Complete source record
{
"id": "0c140ec4ee54cc2aebd555f350dab3e2b5e61cfd56a662750c3165e2fa8d9619",
"url": "https://osv.dev/vulnerability/CVE-2026-33699",
"method": "structured",
"payload": {
"kind": "advisory",
"title": "pypdf: Possible infinite loop during recovery attempts in DictionaryObject.read_from_stream",
"summary": "pypdf is a free and open-source pure-python PDF library. Versions prior to 6.9.2 have a vulnerability in which an attacker can craft a PDF which leads to an infinite loop. This requires reading a file in non-strict mode. This has been fixed in pypdf 6.9.2. If users cannot upgrade yet, consider applying the changes from the patch manually.",
"evidence": "osv:CVE-2026-33699",
"products": [],
"severity": "medium",
"structured": {
"id": "CVE-2026-33699",
"aliases": [
"CVE-2026-33699",
"GHSA-87mj-5ggw-8qc3",
"PYSEC-2026-3012"
],
"metrics": [
{
"type": "CVSS_V4",
"score": "CVSS:4.0/AV:N/AC:L/AT:P/PR:N/UI:N/VC:N/VI:N/VA:H/SC:N/SI:N/SA:N/E:U"
}
],
"affected": [
{
"ranges": [
{
"repo": "https://github.com/py-pdf/pypdf",
"type": "GIT",
"events": [
{
"introduced": "0"
},
{
"fixed": "da867f4961e4ac5ac9d751cba3131c5a1a8777f3"
}
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"database_specific": {
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{
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{
"introduced": "0"
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{
"fixed": "6.9.2"
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"source": "AFFECTED_FIELD",
"strategy": "StringRangeExpression"
},
{
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"source": "REFERENCES_TAG",
"original_tag": "6.9.2"
},
{
"cpe": "cpe:2.3:a:pypdf_project:pypdf:*:*:*:*:*:*:*:*",
"range": [
{
"introduced": "0"
},
{
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}
],
"source": "CPE_RANGE"
}
]
}
}
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],
"database_specific": {
"source": "https://storage.googleapis.com/cve-osv-conversion/osv-output/CVE-2026-33699.json"
}
}
],
"modified": "2026-10-28T02:30:24.217971853Z",
"provider": "osv",
"references": [
"https://github.com/py-pdf/pypdf/releases/tag/6.9.2",
"https://github.com/CVEProject/cvelistV5/tree/main/cves/2026/33xxx/CVE-2026-33699.json",
"https://github.com/py-pdf/pypdf/security/advisories/GHSA-87mj-5ggw-8qc3",
"https://nvd.nist.gov/vuln/detail/CVE-2026-33699",
"https://github.com/py-pdf/pypdf/pull/3693"
],
"provider_metadata": {
"cwe_ids": [
"CWE-835"
],
"cna_assigner": "GitHub_M",
"osv_generated_from": "https://github.com/CVEProject/cvelistV5/tree/main/cves/2026/33xxx/CVE-2026-33699.json"
}
},
"related_cves": [
{
"value": "CVE-2026-33699",
"evidence": "/id"
}
],
"security_relevant": true,
"severity_evidence": "/severity/0/score"
},
"source_id": "core-osv",
"document_id": 490490,
"published_at": "2026-03-26T23:58:42.776+00:00"
}