Pillow is a Python imaging library. Prior to 13.0.0, MpoImageFile.seek() and DcxImageFile.seek() reparse later MPO or DCX frames and replace self._size without rerunning Image._decompression_bomb_check(). A crafted multi-frame image can use a tiny first frame to pass Image.open() and then declare an over-limit later frame. Normal frame iteration through seek(), load(), or ImageSequence.Iterator can decode that frame and commit hundreds of megabytes or more, causing memory-exhaustion denial of service. This issue is fixed in version 13.0.0.
{
"cna_assigner": "GitHub_M",
"cwe_ids": [
"CWE-400",
"CWE-409"
],
"osv_generated_from": "https://github.com/CVEProject/cvelistV5/tree/main/cves/2026/96xxx/CVE-2026-96636.json"
}{
"extracted_events": [
{
"range": [
{
"introduced": "0"
},
{
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}
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"source": "AFFECTED_FIELD",
"strategy": "StringRangeExpression"
},
{
"range": [
{
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"source": "REFERENCES_COMMIT"
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{
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}