A stack-based buffer overflow vulnerability exists in the MFER parsing functionality of The Biosig Project libbiosig 3.9.0 and Master Branch (35a819fa). A specially crafted MFER file can lead to arbitrary code execution. An attacker can provide a malicious file to trigger this vulnerability.This vulnerability manifests on line 8970 of biosig.c on the current master branch (35a819fa), when the Tag is 63: else if (tag==63) { uint8_t tag2=255, len2=255; count = 0; while ((count<len) && !(FlagInfiniteLength && len2==0 && tag2==0)){ curPos += ifread(&tag2,1,1,hdr); curPos += ifread(&len2,1,1,hdr); if (VERBOSE_LEVEL==9) fprintf(stdout,"MFER: tag=%3i chan=%2i len=%-4i tag2=%3i len2=%3i curPos=%i %li count=%4i\n",tag,chan,len,tag2,len2,curPos,iftell(hdr),(int)count); if (FlagInfiniteLength && len2==0 && tag2==0) break; count += (2+len2); curPos += ifread(&buf,1,len2,hdr); Here, the number of bytes read is not the Data Length decoded from the current frame in the file (`len`) but rather is a new length contained in a single octet read from the same input file (`len2`). Despite this, a stack-based buffer overflow condition can still occur, as the destination buffer is still `buf`, which has a size of only 128 bytes, while `len2` can be as large as 255.
| Métrique | Valeur | Interprétation |
|---|---|---|
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AV (Vecteur d'Attaque)
Attack Vector
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Network (N)
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Exploit possible à distance via réseau (HTTP, API, etc.) |
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AC (Complexité d'Attaque)
Attack Complexity
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Low (L)
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Peu de conditions requises pour exploiter |
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PR (Privilèges Requis)
Privileges Required
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None (N)
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Aucune authentification requise |
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UI (Interaction Utilisateur)
User Interaction
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None (N)
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Aucune interaction utilisateur nécessaire |
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S (Périmètre)
Scope
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Unchanged (U)
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Impact reste dans le périmètre du composant compromis |
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C (Impact Confidentialité)
Confidentiality Impact
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High (H)
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Divulgation totale d'informations |
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I (Impact Intégrité)
Integrity Impact
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High (H)
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Modification totale des données possible |
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A (Impact Disponibilité)
Availability Impact
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High (H)
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Interruption totale du service possible |