Malicious PDF — malware analysis report

Static analysis result for SHA-256 f9dec5d3a84001c3…

MALICIOUS

PDF

74.6 KB Created: 2021-08-30 15:45:26 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-10-27
MD5: 31bea0496f65b8b78129fcd6322f96d6 SHA-1: f21d2732bd252cd7c673123090b30abf171b1b07 SHA-256: f9dec5d3a84001c32031c29dc9f00af9f87a257c4fca7f9fd848827980457ea0
156 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment T1204.001 User Execution: Malicious Link

This PDF file was detected as malicious by ClamAV and an ML classifier. Heuristics indicate it functions as a link farm, pointing to multiple compromised WordPress sites and disposable hosting domains. The document body is heavily obfuscated, but the presence of numerous external URIs suggests an attempt to redirect users to malicious content, likely for phishing or malware distribution.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9987

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 http://888chji.com/userfiles/files/xirabiwizijozibo.pdf In PDF document text
    • https://halobysciton.com/wp-content/plugins/formcraft/file-upload/server/content/files/160759af01d19f---wejotenabi.pdfIn PDF document text
    • https://kanat.com/upload/ckfinder/files/jejaketunitozujubijoxujef.pdfIn PDF document text
    • http://lubrifianti-auto.ro/files/file/xujomopeveselarodew.pdfIn PDF document text
    • http://barudan.hk/UploadFile/file/20210728052738598.pdfIn PDF document text
    • https://chilegastronomia.cl/uploads/userfiles/files/88668145225.pdfIn PDF document text
    • http://www.colegiometa.net/home/wp-content/plugins/formcraft/file-upload/server/content/files/16084f7b50c5f3---sugopupulejexabet.pdfIn PDF document text
    • http://tano-cable.com/d/files/62798029558.pdfIn PDF document text
    • https://baxsporthorses.com/userfiles/file/15938120154.pdfIn PDF document text
    • http://lideparts.com/userfiles/file/1622369782.pdfIn PDF document text
    • http://akgikorea.com/file_upload/fck_upfile/file/wetik.pdfIn PDF document text
    • https://efnnma.org/files/file/67823974455.pdfIn PDF document text
    • https://altstudio.be/app/webroot/uploads/file/8975040728.pdfIn PDF document text
    • http://aurora-c.jp/files/files/64752281504.pdfIn PDF document text
    • https://eravukappalpalli.com/userfiles/file/80304140841.pdfIn PDF document text
    • https://udachi.co.th/wp-content/plugins/super-forms/uploads/php/files/6mve95frvnhgeuebbm4q5o5mc4/72677451691.pdfIn PDF document text
    • http://teerosy.com/ipp/images/uploads/files/35414512538.pdfIn PDF document text
    • http://skogsformedling.se/bilder_umeny/File/8830356692.pdfIn PDF document text
    • http://www.1000ena.com/wp-content/plugins/formcraft/file-upload/server/content/files/160a9d0bdc1c10---44244737029.pdfIn PDF document text
    • https://keralahappyjourney.com/ckfinder/userfiles/files/1671522972.pdfIn PDF document text
    • http://www.yourhealthyourchoice.org/wp-content/plugins/formcraft/file-upload/server/content/files/160a3bc7d88e3e---67995076182.pdfIn PDF document text
    • https://promocionesnma.com/wp-content/plugins/super-forms/uploads/php/files/e8ec96291097d78d5ffa8a00a268af76/11530852085.pdfIn PDF document text
    • https://advicezone.org.uk/wp-content/plugins/super-forms/uploads/php/files/rlc0tq1nvkqdcjlstivj215i5v/wunepew.pdfIn PDF document text
    • https://feedproxy.google.com/~r/skout/mBVl/~3/FevRqgeaUVY/uplcv?utm_term=the+financial+numbers+gamePDF 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_off0000c0db.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xC0DB 10768 bytes
SHA-256: 9582065e88f1c70fd090f74382241bb35765dfcf31fd1414c1e9e4fe1dff609e
font_01_sfnt_off0000d95c.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xD95C 16500 bytes
SHA-256: b894b175eab601bb1b97f79f5f3b28cb9de5662f889ca12dfc8e678d271e5ae0
font_02_sfnt_off000103ac.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x103AC 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1