Malicious PDF — malware analysis report

Static analysis result for SHA-256 8aac6f6050f5214a…

MALICIOUS

PDF

82.8 KB Created: 2021-09-06 11:35:06 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-10-05
MD5: f834ca40d7e71e1ef00a6be791d18ec9 SHA-1: 6677bdb648652561366b0883182ab20d3f455f22 SHA-256: 8aac6f6050f5214a31b5206e623b41c823cf4d32d21e10c014a0a4537c0fa4ae
156 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment T1204.002 Malicious Link

The PDF file was identified as malicious by ClamAV and an ML classifier, indicating a high likelihood of malicious intent. Heuristic analysis revealed that the document functions as a link farm, directing users to multiple external websites, many of which are hosted on compromised CMS platforms or disposable domains. The presence of numerous unknown URLs suggests a phishing or SEO poisoning campaign.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9974

Heuristics 6

  • ClamAV: Pdf.Phishing.Trojan-d2568dad23a94d95-d2568dad23a94d95-10044375-0 critical CLAMAV_DETECTION
    ClamAV detected this file as malware: Pdf.Phishing.Trojan-d2568dad23a94d95-d2568dad23a94d95-10044375-0
  • PDF link farm points to compromised-WordPress upload storage medium PDF_COMPROMISED_CMS_UPLOAD_LINK_FARM
    PDF contains multiple clickable links, across many distinct hosts, whose targets are random-slug files parked in the upload directories of vulnerable WordPress form plugins (FormCraft, Super Forms). This is the hallmark of the 'free document/template' SEO phishing PDF family, which ranks for search queries and routes users into payload/redirect chains hosted on compromised sites. The PDF itself carries no exploit — the risk is the linked destinations.
  • 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://www.heainc.com/wp-content/plugins/formcraft/file-upload/server/content/files/160ee3c9f2f1ec---70216160361.pdf In PDF document text
    • http://akkoryazilim.com/userfiles/file/wekuzixezekokobuturozine.pdfIn PDF document text
    • http://www.rolstoellift.com/wp-content/plugins/formcraft/file-upload/server/content/files/1609cd51dd50b8---jepezagigasekagaso.pdfIn PDF document text
    • http://tfh-filter.hu/_user/file/kixodujowevosiwirurokulis.pdfIn PDF document text
    • https://alsterparkett.de/wp-content/plugins/super-forms/uploads/php/files/j1jc5k912eba6h0jn8hai5457i/37182338070.pdfIn PDF document text
    • https://noblacklist.pro/web/img/podborky/files/votedajejurixinisonoluw.pdfIn PDF document text
    • https://arerp.kr/data/file///nodunorarenapasosibew.pdfIn PDF document text
    • http://newbiesites.com/userfiles/file/sofefenozipeb.pdfIn PDF document text
    • http://www.moyekolodin.com/files/62497666687.pdfIn PDF document text
    • https://ckmusicdesign.nluserfiles/file/22085892069.pdfIn PDF document text
    • https://travolution.travel/wp-content/plugins/super-forms/uploads/php/files/39321ba367384e17b3f39afbb6d7e6a4/68953508665.pdfIn PDF document text
    • http://www.x454.com/wp-content/plugins/super-forms/uploads/php/files/0g5fb1fsruaee1aukpqp5cpgc5/puwawijima.pdfIn PDF document text
    • https://www.hagensmarketing.com/wp-content/plugins/formcraft/file-upload/server/content/files/1607cf8448ba56---xosuduxakoma.pdfIn PDF document text
    • https://www.adler-leitishofen.de/wp-content/plugins/formcraft/file-upload/server/content/files/160d66a7fbd4ec---bewirudibodoruzu.pdfIn PDF document text
    • http://sonnenheizung.ch/fckeditor/editor/images/file/gufogodunopabovevagexe.pdfIn PDF document text
    • https://tainandentist.com/uploads/files/202109021727344696.pdfIn PDF document text
    • http://okmarin.ru/userfiles/file/39450682183.pdfIn PDF document text
    • http://crisismobile.com/ckfinder/userfiles/files/55362160045.pdfIn PDF document text
    • http://terapie-psi.ro/wp-content/plugins/formcraft/file-upload/server/content/files/16072e124e243a---81883048552.pdfIn PDF document text
    • https://www.expoagrogto.com/wp-content/plugins/super-forms/uploads/php/files/lk768knk6kf4s47svjbasp4045/90126486804.pdfIn PDF document text
    • http://alexanderkanevskyartgallery.com/clientMedia/file/7452322163.pdfIn PDF document text
    • http://www.corazondelsol.es/ckfinder/userfiles/files/42178848630.pdfIn PDF document text
    • https://www.mozartcantat.nl/wp-content/plugins/formcraft/file-upload/server/content/files/1611e4a1b2c8e4---modovifapakid.pdfIn PDF document text
    • http://seasonsblinds.com/uploads/ckfinder/userfiles/files/20454195327.pdfIn PDF document text
    • http://ski-experience-japan.com/images/blog//file/nixuxi.pdfIn PDF document text
    • https://feedproxy.google.com/~r/1eyvgo/aqOO/~3/cv9VXjIrmdE/uplcv?utm_term=electricity+and+magnetism+physics+book+pdfPDF 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_off0000de57.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xDE57 11396 bytes
SHA-256: 50544c30f25626b1ff9e85c7e032e309cd6f2b04b7a396006ffa504ac3be9507
font_01_sfnt_off0000f88c.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xF88C 17196 bytes
SHA-256: 114fc81f46b569a91dd34d5f8c61e8b15ae2702c0aa71ef7a82690670ca25cce
font_02_sfnt_off00012533.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x12533 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1