Malicious PDF — malware analysis report

Static analysis result for SHA-256 9316cd27ee7a5d02…

MALICIOUS

PDF

96.8 KB Created: 2021-07-01 10:16:53 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3)
MD5: 08c96259ab0e3288bdad605b04b9b693 SHA-1: d2a75f2eb40afac7f58be160b3ae745d6ac113ed SHA-256: 9316cd27ee7a5d025360c954b97fcde46184375aba322cc8397178cb601180d9
156 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment T1203 Exploitation for Client Execution

The file was detected as malicious by ClamAV and an ML classifier, with heuristics indicating it functions as a link farm pointing to compromised websites. The PDF contains numerous external URIs, many of which are hosted on disposable domains or compromised CMS upload storage, suggesting an attempt to distribute malicious content or phish users. The presence of multiple PDF-specific heuristics and the overall structure strongly indicate a malicious PDF designed for initial access.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9910

Heuristics 6

  • ClamAV: Pdf.Phishing.Trojan-d2528dad23a95d95-d2528dad23a95d95-10044376-0 critical CLAMAV_DETECTION
    ClamAV detected this file as malware: Pdf.Phishing.Trojan-d2528dad23a95d95-d2528dad23a95d95-10044376-0
  • 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://huntic.ru/uplcv?utm_term=an+introduction+to+the+mathematics+of+financial+derivatives+pdf
    • https://maloneslandscape.com/wp-content/plugins/formcraft/file-upload/server/content/files/16075f122e82eb---jafanoxamagukijok.pdf
    • http://promador.pl/userfiles/file/jefaromefureruvedux.pdf
    • http://divapharma.com/uploaded/file/silozipanamavixibozeter.pdf
    • https://reifenscho.de/wp-content/plugins/formcraft/file-upload/server/content/files/160b7465d0fab1---zegegumofagijatajakof.pdf
    • http://afgventuregroup.com/cfiles/file/nuwevozijow.pdf
    • http://www.reenactmentmarket.eu/images/wyswig_images/file/jadogewilo.pdf
    • http://bsbcarpet.com/userfiles/file/15738811859.pdf
    • http://massageindex.nl/images/uploads/24693958833.pdf
    • http://norilskgu.ru/userfiles/file/71837631039.pdf
    • https://www.sir.co.uk/wp-content/plugins/formcraft/file-upload/server/content/files/160911787db284---siranelodixam.pdf
    • http://zulassungsservice4you.de/bilder/file/lexodujamavuguxa.pdf
    • https://agsposure.org/wp-content/plugins/super-forms/uploads/php/files/02b83a53008a05ed5c49401a49fa4c95/zejagi.pdf
    • http://escolacaritas.com/wp-content/plugins/formcraft/file-upload/server/content/files/16075a1f360c87---dilovaxevopabosefawiwupob.pdf
    • https://m-co.de/wp-content/plugins/super-forms/uploads/php/files/g61flnusulnth6mu2v18feehk2/fadizuxetimomunumenebuni.pdf
    • http://www.nuricomuvakfi.org/wp-content/plugins/super-forms/uploads/php/files/hap3imvou4m54dhg2d7atroku2/vixepofuwizawojifebozinax.pdf
    • http://becro-plast.hr/wp-content/plugins/formcraft/file-upload/server/content/files/1608748c3e2f77---85692071463.pdf
    • https://truck-diagnostic.ru/wp-content/plugins/super-forms/uploads/php/files/756b2909d2ef5b4fb2678c53bf069315/mufoxip.pdf
    • http://multiseal.com.ph/wp-content/plugins/formcraft/file-upload/server/content/files/160bb8fa8ed690---bimowepidaleveza.pdf
    • https://elitteaccesorios.com/wp-content/plugins/super-forms/uploads/php/files/fc3mlc5ij93a1opb290eiqotl6/98356086589.pdf
    • http://www.lugashotel.com/data/editorfile/70349849558.pdf
    • http://www.inhd.com.br/wp-content/plugins/formcraft/file-upload/server/content/files/160703e71e1c26---zubawufevuse.pdf
    • http://permanentnimakeup-brno.cz/userfiles/files/37540287650.pdf
    • https://stvorki.ru/files/file/76701875208.pdf
    • http://modellszerviz.hu/userfiles/file/lufavubejefelumawiva.pdf
    • 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 4

Files carved from inside the sample during analysis.

FilenameKindSourceSize
font_00_sfnt_off0000fcaa.bin
4894f75c7bca657c16f9acd51102e5c51d5b9c88010314c2e21b488b2f3b7eb7
pdf-font-stream PDF embedded font (sfnt) at offset 0xFCAA 16340 bytes
font_01_sfnt_off000112f4.bin
9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
pdf-font-stream PDF embedded font (sfnt) at offset 0x112F4 16792 bytes
font_02_sfnt_off00012b0b.bin
4ffce512506dc3bb6c2d53d8995e75800bd43242ff94b7e94013d1d47e5b1452
pdf-font-stream PDF embedded font (sfnt) at offset 0x12B0B 11032 bytes
font_03_sfnt_off00014496.bin
07a3120bd37ba57cdc667caa2411846475c33510806516baa21a36be172b9c35
pdf-font-stream PDF embedded font (sfnt) at offset 0x14496 18296 bytes