A null pointer dereference occurs in the function breakwordforoverflowwrap() in MuPDF 1.26.4 when rendering a malformed EPUB document. Specifically, the function calls fzhtmlsplitflow() to split a FLOWWORD node, but does not check if node->next is valid before accessing node->next->overflow_wrap, resulting in a crash if the split fails or returns a partial node chain.
{
"cna_assigner": "mitre",
"osv_generated_from": "https://github.com/CVEProject/cvelistV5/tree/main/cves/2025/55xxx/CVE-2025-55780.json"
}"2026-07-09T19:48:02Z"
"https://storage.googleapis.com/cve-osv-conversion/osv-output/CVE-2025-55780.json"
[
{
"signature_type": "Line",
"target": {
"file": "source/pdf/pdf-annot.c"
},
"deprecated": false,
"digest": {
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],
"threshold": 0.9
},
"id": "CVE-2025-55780-7e8d1d45",
"source": "https://github.com/artifexsoftware/mupdf/commit/12b4cdcd0b70231e0dc5cd777abd9339d61230ab",
"signature_version": "v1"
},
{
"signature_type": "Function",
"target": {
"file": "source/pdf/pdf-annot.c",
"function": "pdf_nuke_annots"
},
"deprecated": false,
"digest": {
"length": 488.0,
"function_hash": "140261027352262709890614608527069886385"
},
"id": "CVE-2025-55780-867ef66a",
"source": "https://github.com/artifexsoftware/mupdf/commit/12b4cdcd0b70231e0dc5cd777abd9339d61230ab",
"signature_version": "v1"
}
]