calibre is an e-book manager. In 9.1.0 and earlier, a path traversal vulnerability in Calibre's EPUB conversion allows a malicious EPUB file to corrupt arbitrary existing files writable by the Calibre process. During conversion, Calibre resolves CipherReference URI from META-INF/encryption.xml to an absolute filesystem path and opens it in read-write mode, even when it points outside the conversion extraction directory. This vulnerability is fixed in 9.2.0.
{
"cwe_ids": [
"CWE-22",
"CWE-73",
"CWE-94"
],
"osv_generated_from": "https://github.com/CVEProject/cvelistV5/tree/main/cves/2026/25xxx/CVE-2026-25636.json",
"cna_assigner": "GitHub_M",
"unresolved_ranges": [
{
"extracted_events": [
{
"fixed": "9.2.0"
}
],
"source": "AFFECTED_FIELD"
}
]
}