pypdf is a free and open-source pure-python PDF library. Prior to 6.18.1, a crafted PDF containing a partially malformed /FlateDecode stream with padded data can force pypdf/filters.py to use inefficient byte-by-byte decompression while the earlier recovery counter fails to advance for bytes that successfully decode, causing long runtimes and application unavailability. This is a residual issue after the malformed FlateDecode recovery fix. This issue is fixed in version 6.18.1.
{
"cna_assigner": "GitHub_M",
"cwe_ids": [
"CWE-400",
"CWE-407"
],
"osv_generated_from": "https://github.com/CVEProject/cvelistV5/tree/main/cves/2026/102xxx/CVE-2026-102997.json"
}{
"extracted_events": [
{
"cpe": "cpe:2.3:a:pypdf_project:pypdf:*:*:*:*:*:*:*:*",
"range": [
{
"introduced": "0"
},
{
"fixed": "6.18.1"
}
],
"source": "CPE_RANGE"
},
{
"range": [
{
"fixed": "d9d38cf99b115deb562d3b68f36c33027bc04f79"
}
],
"source": "REFERENCES_COMMIT"
},
{
"original_tag": "6.18.1",
"range": [
{
"fixed": "caf8cde51a9c698c98f50a1930e3dffba222bb4e"
}
],
"source": "REFERENCES_TAG"
}
]
}