Malicious PDF — malware analysis report

Static analysis result for SHA-256 9dbc8a61571a6560…

MALICIOUS

PDF

73.3 KB Created: 2021-09-21 12:57:08 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-11-25
MD5: 18158c5758a48edc26fd73776f248373 SHA-1: 077f70527bb3608b4e9386da5653e82023eb549a SHA-256: 9dbc8a61571a6560e464ab2496e1233f7ac18077e87a8226cbef4d23741dbe35
66 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment

The PDF contains numerous embedded URLs, with a high heuristic firing indicating it is a link farm on disposable hosting. The ML classifier also flagged the PDF as malicious. While no scripts were explicitly extracted, the presence of many external links suggests an intent to redirect the user to potentially malicious sites, aligning with spearphishing attachment tactics.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9973

Heuristics 4

  • Small PDF is a non-clustered link farm on disposable hosting medium PDF_SEO_DISPOSABLE_LINK_FARM
    Small PDF contains many clickable external PDF links spread thin across many distinct hosts (no single dominant host), corroborated by a utm_term SEO-redirector link and/or links parked on free/disposable content hosts. This is the 'free document/template' SEO phishing PDF family, which ranks for search queries and routes users into payload/redirect chains, rather than a normal document citation pattern. The PDF itself carries no exploit — the risk is the linked destinations.
  • External URI info PDF_URI
    PDF contains an external URL action
  • Object number defined twice with different bodies info PDF_DUPLICATE_OBJ_BODY_INCREMENTAL
    The same indirect object (N G) is defined more than once with different body bytes. First-wins and last-wins readers will resolve different content, which is a parser-confusion shape used by targeted PDFs. Body-only differences are common in benign incremental updates, so severity is raised only when the duplicate carries active content.
  • Embedded URL info EMBEDDED_URL
    One or more URLs were extracted from the document. The URL itself is not a detection — see the per-URL labels for which channel (macro, JS, link annotation, document body, ...) reached each URL.
    URL https://buyafranchise.org/files/files/59194172779.pdf In PDF document text
    • https://everestart.com/images/stories/file/54851833118.pdfIn PDF document text
    • http://urotunisia.com/uploads/FCK_files/file/jasit.pdfIn PDF document text
    • http://eiak.org/upload/editor/files/62428103061.pdfIn PDF document text
    • https://horgaszvelem.elelmiszer-hazhozszallitas.hu/ckfinder/userfiles/files/94708755305.pdfIn PDF document text
    • http://yepuco.com/uploads/files/77654551498.pdfIn PDF document text
    • https://www.nhabe.com.vn/ckfinder/userfiles/files/30750615841.pdfIn PDF document text
    • http://sanzmendia.com/userfiles/files/64909955602.pdfIn PDF document text
    • http://chekeeh.ir/basefile/chekeehir/files/vufixed.pdfIn PDF document text
    • http://xn--dlek-5qa.com/admin/UserFiles/file/kepalexivufedajavozemita.pdfIn PDF document text
    • https://martan.es/cenavarra_userfiles/files/60039757093.pdfIn PDF document text
    • http://choragwica.pl/userfiles/file/9403556625.pdfIn PDF document text
    • http://megat.pl/uploaded/fck_files/file/pixur.pdfIn PDF document text
    • https://infotechb2blite.com/bot/ckfinder/uf/files/gukenupufiraganofixewil.pdfIn PDF document text
    • http://kssi.ir/public/userfiles/file/2880984564.pdfIn PDF document text
    • http://rheumatology.institute/upload/content/file/66080032760.pdfIn PDF document text
    • http://www.udelimpa.es/ckfinder/userfiles/files/6871540784.pdfIn PDF document text
    • http://alpes-maritimes.proximeo.com/ckfinder/userfiles/files/81697833346.pdfIn PDF document text
    • https://www.sblending.com.au/wp-content/plugins/formcraft/file-upload/server/content/files/1613b7a5817649---12802128595.pdfIn PDF document text
    • http://thesprotia.gr/uploads/file/47911342176.pdfIn PDF document text
    • http://hvpeds.com/upload/contents/file/31750754820.pdfIn PDF document text
    • https://www.cir.cloud/wp-content/plugins/formcraft/file-upload/server/content/files/161407fee3560a---9577222109.pdfIn PDF document text
    • http://top-rubber.com/admin/fckeditor/editor/filemanager/connectors/upload/file/63230319060.pdfIn PDF document text
    • http://etalentlink.com/uploadfile/file///2021090211021098.pdfIn PDF document text
    • https://feedproxy.google.com/~r/1eyvgo/aqOO/~3/A3Ryygt5BCM/uplcv?utm_term=samsung+galaxy+s3+neo+firmwarePDF link annotation
    • http://www.w3.org/1999/02/22-rdf-syntax-ns#In PDF document text
    • http://purl.org/dc/elements/1.1/In PDF document text
    • http://ns.adobe.com/pdf/1.3/In PDF document text
    • http://ns.adobe.com/xap/1.0/In PDF document text
    • http://ns.adobe.com/xap/1.0/mm/In PDF document text
    • http://ns.adobe.com/xap/1.0/rights/In PDF document text
    • http://dejavu.sourceforge.netIn PDF document text
    • http://dejavu.sourceforge.net/wiki/index.php/LicenseIn PDF document text

Extracted artifacts 3

Files carved from inside the sample during analysis.

FilenameKindSourceSize
font_00_sfnt_off0000ba4f.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xBA4F 16688 bytes
SHA-256: 0f635f385f4949efc5dc23556930b392cb755e0d061a828e691c2b6af5485e6b
font_01_sfnt_off0000e58d.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xE58D 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
font_02_sfnt_off0000fda4.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xFDA4 11108 bytes
SHA-256: eb9fbdc8f6be6324e8c4f0ddd4b83e743d682adb780a1ea87df65d5f3495d4b3