Malicious PDF — malware analysis report

Static analysis result for SHA-256 5c6833ebd186801e…

MALICIOUS

PDF

82.3 KB Created: 2021-09-07 17:45:49 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3)
MD5: 239c3c8153902a6fd51f8ef71e33716a SHA-1: f78b7ebe0d1a4c8b54a6016b529fc6d339df12d6 SHA-256: 5c6833ebd186801e861d02f83b141259597deca72f857cc933952fb480b8f8d1
156 Risk Score

Malware Insights

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

The PDF contains numerous embedded URLs, many of which point to compromised WordPress upload directories or other potentially malicious sites. The ML classifier and ClamAV detection strongly indicate malicious intent, likely related to phishing or malware delivery through these links. The document body is heavily obfuscated and does not provide direct user-facing text, but the heuristic firings clearly point to a link farm attack pattern.

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 http://mytmbc.org/fckimage/file/bifofopadebom.pdf
    • http://www.uppld.org/wp-content/plugins/formcraft/file-upload/server/content/files/160c177e8931dc---jirupirikoseminivavagizob.pdf
    • http://omonetach.pl/foto/ilustracje/file/xojesurazawoxidavugusezil.pdf
    • https://abeess.com/userfiles/file/48012330703.pdf
    • http://multiseal.com.ph/wp-content/plugins/formcraft/file-upload/server/content/files/160a6fb20825c9---47826180932.pdf
    • https://rhagro.com.mx/wp-content/plugins/super-forms/uploads/php/files/5f5a51d072d8bd09968c86c99b66c705/8880847037.pdf
    • http://sugarfree-gelato.com/upload/file/netukosizalojofuvufekon.pdf
    • http://www.emporiocaritaspisa.it/wordpress/wp-content/plugins/formcraft/file-upload/server/content/files/1608b113dcba0e---52340681228.pdf
    • http://www.klpreschool.com/wp-content/plugins/formcraft/file-upload/server/content/files/160709f2fd605c---6138249517.pdf
    • http://unesco-mediain.cz/fckfiles/file/megigujurexubababi.pdf
    • https://maidintown.co.uk/wp-content/plugins/super-forms/uploads/php/files/0eead9c30e02e449c79d80dcacf5498a/selenit.pdf
    • https://eletvital.hu/uploads/files/17012346354.pdf
    • https://zazilha.com.mx/wp-content/plugins/super-forms/uploads/php/files/8d652eae879531e3ee9585eec3fbf07c/zoduj.pdf
    • https://sellos-mecanicos.com/wp-content/plugins/super-forms/uploads/php/files/63ff8897512608170f9709d1a8bae59d/guxosaxefexapoku.pdf
    • https://www.ideakliniksisli.com/wp-content/plugins/formcraft/file-upload/server/content/files/16087015fb3611---vifimulutegux.pdf
    • http://diclenakliyat.com/userfiles/file/toditufojagogixoto.pdf
    • https://alhurwallpaper.com/Files/files/rusejofagimomew.pdf
    • http://cappellastudio.it/userfiles/files/xisinudufupasugije.pdf
    • http://vudafrique.com/wp-content/plugins/super-forms/uploads/php/files/d7722c45fcd515ecc656bb96916f3570/vomeniwu.pdf
    • https://sayurmateng.com/contents//files/kanelimareniwumi.pdf
    • http://beergolfers.com/blog/images/file/21321133681.pdf
    • https://thewentworthco.com/wp-content/plugins/super-forms/uploads/php/files/d1domtm2dvhc77av1n7gak122u/zelumexirizesubawivowedep.pdf
    • https://beldapromosyon.com/calisma2/files/uploads/guzemo.pdf
    • https://www.hotelamoha.it/wp-content/plugins/formcraft/file-upload/server/content/files/160e4e19be142e---55781403201.pdf
    • https://feedproxy.google.com/~r/skout/mBVl/~3/6naE_Nh8_CY/uplcv?utm_term=convert+docx+to+pdf+software
    • http://www.w3.org/1999/02/22-rdf-syntax-ns#
    • http://purl.org/dc/elements/1.1/
    • http://ns.adobe.com/pdf/1.3/
    • http://ns.adobe.com/xap/1.0/
    • http://ns.adobe.com/xap/1.0/mm/
    • http://ns.adobe.com/xap/1.0/rights/
    • http://dejavu.sourceforge.net
    • http://dejavu.sourceforge.net/wiki/index.php/License

Extracted artifacts 3

Files carved from inside the sample during analysis.

FilenameKindSourceSize
font_00_sfnt_off0000de6e.bin
9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
pdf-font-stream PDF embedded font (sfnt) at offset 0xDE6E 16792 bytes
font_01_sfnt_off0000f685.bin
f7e5421cbfc5e0c75b639e47c9161f047fc353b459b514b9aa327fede54997e5
pdf-font-stream PDF embedded font (sfnt) at offset 0xF685 10760 bytes
font_02_sfnt_off00010f89.bin
c2c0065c7decd1eb4134567e91ad87c62677a87716994d18f43821472b255f42
pdf-font-stream PDF embedded font (sfnt) at offset 0x10F89 16952 bytes