Medium
pypdf: Manipulated FlateDecode predictor parameters can exhaust RAM
Type: advisorySources: OSV
pypdf is a free and open-source pure-python PDF library. An attacker who uses a vulnerability present in versions prior to 6.10.2 can craft a PDF which leads to the RAM being exhausted. This requires accessing a stream compressed using `/FlateDecode` with a `/Predictor` unequal 1 and large predictor parameters. This has been fixed in pypdf 6.10.2. As a workaround, one may apply the changes from the patch manually.
- Products
- Not specified
- Affected versions
- Not specified
- Fixed versions
- Not specified
- CVEs
- CVE-2026-41312
- Confirmed fixed CVEs
- Not specified
- Updated in this feed
- 3 Nov 2026, 11:04 UTC · Revision 1
Source evidence
pypdf: Manipulated FlateDecode predictor parameters can exhaust RAM
core-osv · Original sourcePublished 22 Apr 2026, 21:02 UTC
pypdf is a free and open-source pure-python PDF library. An attacker who uses a vulnerability present in versions prior to 6.10.2 can craft a PDF which leads to the RAM being exhausted. This requires accessing a stream compressed using `/FlateDecode` with a `/Predictor` unequal 1 and large predictor parameters. This has been fixed in pypdf 6.10.2. As a workaround, one may apply the changes from the patch manually.
osv:CVE-2026-41312
Complete source record
{
"id": "13b8982515bb96f21a21d119960d6e61df3b2e47765ce0d889e13076f687b12a",
"url": "https://osv.dev/vulnerability/CVE-2026-41312",
"method": "structured",
"payload": {
"kind": "advisory",
"title": "pypdf: Manipulated FlateDecode predictor parameters can exhaust RAM",
"summary": "pypdf is a free and open-source pure-python PDF library. An attacker who uses a vulnerability present in versions prior to 6.10.2 can craft a PDF which leads to the RAM being exhausted. This requires accessing a stream compressed using `/FlateDecode` with a `/Predictor` unequal 1 and large predictor parameters. This has been fixed in pypdf 6.10.2. As a workaround, one may apply the changes from the patch manually.",
"evidence": "osv:CVE-2026-41312",
"products": [],
"severity": "medium",
"structured": {
"id": "CVE-2026-41312",
"aliases": [
"CVE-2026-41312",
"GHSA-7gw9-cf7v-778f",
"PYSEC-2026-3011"
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"metrics": [
{
"type": "CVSS_V4",
"score": "CVSS:4.0/AV:L/AC:L/AT:N/PR:N/UI:P/VC:N/VI:N/VA:L/SC:N/SI:N/SA:N"
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"database_specific": {
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],
"modified": "2026-10-28T02:30:28.296756945Z",
"provider": "osv",
"references": [
"https://github.com/py-pdf/pypdf/releases/tag/6.10.2",
"https://github.com/CVEProject/cvelistV5/tree/main/cves/2026/41xxx/CVE-2026-41312.json",
"https://github.com/py-pdf/pypdf/security/advisories/GHSA-7gw9-cf7v-778f",
"https://nvd.nist.gov/vuln/detail/CVE-2026-41312",
"https://github.com/py-pdf/pypdf/commit/ac734dab4eef92bcce50d503949b4d9887d89f11",
"https://github.com/py-pdf/pypdf/pull/3734"
],
"provider_metadata": {
"cwe_ids": [
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],
"cna_assigner": "GitHub_M",
"osv_generated_from": "https://github.com/CVEProject/cvelistV5/tree/main/cves/2026/41xxx/CVE-2026-41312.json"
}
},
"related_cves": [
{
"value": "CVE-2026-41312",
"evidence": "/id"
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],
"security_relevant": true,
"severity_evidence": "/severity/0/score"
},
"source_id": "core-osv",
"document_id": 494650,
"published_at": "2026-04-22T21:02:53.156+00:00"
}