High
pypdf: Possible large memory usage when parsing font data
Type: advisorySources: OSV
pypdf is a free and open-source pure-python PDF library. Prior to 6.18.1, a crafted PDF can provide a TrueType or Type1 simple font with an unusually large /Widths array, causing pypdf/_font.py Font._collect_tt_t1_character_widths to process entries beyond the 256 character codes meaningful for a simple font and consume excessive memory during operations such as text extraction. This issue is fixed in version 6.18.1.
- Products
- Not specified
- Affected versions
- Not specified
- Fixed versions
- Not specified
- CVEs
- CVE-2026-102996
- Confirmed fixed CVEs
- Not specified
- Updated in this feed
- 3 Nov 2026, 15:56 UTC · Revision 1
Source evidence
pypdf: Possible large memory usage when parsing font data
core-osv · Original sourcePublished 30 Sept 2026, 20:03 UTC
pypdf is a free and open-source pure-python PDF library. Prior to 6.18.1, a crafted PDF can provide a TrueType or Type1 simple font with an unusually large /Widths array, causing pypdf/_font.py Font._collect_tt_t1_character_widths to process entries beyond the 256 character codes meaningful for a simple font and consume excessive memory during operations such as text extraction. This issue is fixed in version 6.18.1.
osv:CVE-2026-102996
Complete source record
{
"id": "7405958c16d39a943a51ffa2dac51ff496b8c4c5874e7401d908e80b31a6014b",
"url": "https://osv.dev/vulnerability/CVE-2026-102996",
"method": "structured",
"payload": {
"kind": "advisory",
"title": "pypdf: Possible large memory usage when parsing font data",
"summary": "pypdf is a free and open-source pure-python PDF library. Prior to 6.18.1, a crafted PDF can provide a TrueType or Type1 simple font with an unusually large /Widths array, causing pypdf/_font.py Font._collect_tt_t1_character_widths to process entries beyond the 256 character codes meaningful for a simple font and consume excessive memory during operations such as text extraction. This issue is fixed in version 6.18.1.",
"evidence": "osv:CVE-2026-102996",
"products": [],
"severity": "high",
"structured": {
"id": "CVE-2026-102996",
"aliases": [
"CVE-2026-102996",
"GHSA-g9cg-prrw-2r8q",
"PYSEC-2026-4155"
],
"metrics": [
{
"type": "CVSS_V4",
"score": "CVSS:4.0/AV:N/AC:L/AT:N/PR:N/UI:N/VC:N/VI:N/VA:H/SC:N/SI:N/SA:N"
}
],
"affected": [
{
"ranges": [
{
"repo": "https://github.com/py-pdf/pypdf",
"type": "GIT",
"events": [
{
"introduced": "0"
},
{
"fixed": "caf8cde51a9c698c98f50a1930e3dffba222bb4e"
},
{
"fixed": "0fb26eb8cdd01c44b3b2c9fe8329751be2f7cfd5"
}
],
"database_specific": {
"extracted_events": [
{
"cpe": "cpe:2.3:a:pypdf_project:pypdf:*:*:*:*:*:*:*:*",
"range": [
{
"introduced": "0"
},
{
"fixed": "6.18.1"
}
],
"source": "CPE_RANGE"
},
{
"range": [
{
"fixed": "0fb26eb8cdd01c44b3b2c9fe8329751be2f7cfd5"
}
],
"source": "REFERENCES_COMMIT"
},
{
"range": [
{
"fixed": "caf8cde51a9c698c98f50a1930e3dffba222bb4e"
}
],
"source": "REFERENCES_TAG",
"original_tag": "6.18.1"
}
]
}
}
],
"versions": [
"6.18.0",
"6.17.0",
"6.16.2",
"6.16.1",
"6.16.0",
"6.15.0",
"6.14.2",
"6.14.1",
"6.14.0",
"6.13.3",
"6.13.2",
"6.13.1",
"6.13.0",
"6.12.2",
"6.12.1",
"6.12.0",
"6.11.0",
"6.10.2",
"6.10.1",
"6.10.0",
"6.9.2",
"6.9.1",
"6.9.0",
"6.8.0",
"6.7.5",
"6.7.4",
"6.7.3",
"6.7.2",
"6.7.1",
"6.7.0",
"6.6.2",
"6.6.1",
"6.6.0",
"6.5.0",
"6.4.2",
"6.4.1",
"6.4.0",
"6.3.0",
"6.2.0",
"6.1.3",
"6.1.2",
"6.1.1",
"6.1.0",
"6.0.0",
"5.9.0",
"5.8.0",
"5.7.0",
"5.6.1",
"5.6.0",
"5.5.0",
"5.4.0",
"5.3.1",
"5.3.0",
"5.2.0",
"5.1.0",
"5.0.1",
"5.0.0",
"4.3.1",
"4.3.0",
"4.2.0",
"4.1.0",
"4.0.2",
"4.0.1",
"4.0.0",
"3.17.4",
"3.17.3",
"3.17.2",
"3.17.1",
"3.17.0",
"3.16.4",
"3.16.3",
"3.16.2",
"3.16.1",
"3.16.0",
"3.15.5",
"3.15.4",
"3.15.3",
"3.15.2",
"3.15.1",
"3.15.0",
"3.14.0",
"3.13.0",
"3.12.2",
"3.12.1",
"3.12.0",
"3.11.1",
"3.11.0",
"3.10.0",
"3.9.1",
"3.9.0",
"3.8.1",
"3.8.0",
"3.7.1",
"3.7.0",
"3.6.0",
"3.5.2",
"3.5.1",
"3.5.0",
"3.4.1",
"3.4.0",
"3.3.0",
"3.2.1",
"3.2.0",
"3.0.0",
"3.1.0",
"2.12.1",
"2.12.0",
"2.11.2",
"2.11.1",
"2.11.0",
"2.10.9",
"2.10.8",
"2.10.7",
"2.10.6",
"2.10.5",
"2.10.4",
"2.10.3",
"2.10.2",
"2.10.1",
"2.10.0",
"2.9.0",
"2.8.1",
"2.8.0",
"2.7.0",
"2.6.0",
"2.5.0",
"2.4.2",
"2.4.1",
"2.4.0",
"2.3.1",
"2.3.0",
"2.2.1",
"2.2.0",
"2.1.1",
"2.1.0",
"2.0.0",
"1.28.2",
"1.28.1",
"1.28.0",
"1.27.12",
"1.27.11",
"1.27.10",
"1.27.9",
"1.27.8",
"1.27.7",
"1.27.6",
"1.27.5",
"1.27.4",
"1.27.3",
"1.27.2",
"1.27.1",
"1.27.0",
"v1.24",
"1.26.0",
"v1.25.1",
"v1.25",
"v1.23",
"v1.22",
"v1.21",
"v1.20",
"v1.19",
"v1.18",
"v1.17"
],
"database_specific": {
"source": "https://storage.googleapis.com/cve-osv-conversion/osv-output/CVE-2026-102996.json"
}
}
],
"modified": "2026-10-28T02:30:30.463624057Z",
"provider": "osv",
"references": [
"https://github.com/py-pdf/pypdf/releases/tag/6.18.1",
"https://github.com/CVEProject/cvelistV5/tree/main/cves/2026/102xxx/CVE-2026-102996.json",
"https://github.com/py-pdf/pypdf/security/advisories/GHSA-g9cg-prrw-2r8q",
"https://nvd.nist.gov/vuln/detail/CVE-2026-102996",
"https://github.com/py-pdf/pypdf/commit/0fb26eb8cdd01c44b3b2c9fe8329751be2f7cfd5",
"https://github.com/py-pdf/pypdf/pull/4072"
],
"provider_metadata": {
"cwe_ids": [
"CWE-400"
],
"cna_assigner": "GitHub_M",
"osv_generated_from": "https://github.com/CVEProject/cvelistV5/tree/main/cves/2026/102xxx/CVE-2026-102996.json"
}
},
"related_cves": [
{
"value": "CVE-2026-102996",
"evidence": "/id"
}
],
"security_relevant": true,
"severity_evidence": "/severity/0/score"
},
"source_id": "core-osv",
"document_id": 497059,
"published_at": "2026-09-30T20:03:55.88+00:00"
}