Malicious PDF — malware analysis report

Static analysis result for SHA-256 597e1ba0c9ab7d4f…

MALICIOUS

PDF

69.6 KB Created: 2021-09-30 19:18:16 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-11-25
MD5: cb639a5a7934a026185c5860465006e2 SHA-1: 7751405cf653e504d946b20795dbc58935935d51 SHA-256: 597e1ba0c9ab7d4f61b29d0198b8e0ffb65bb8da92e7e7b2d7977ecddb6685b9
156 Risk Score

Malware Insights

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

The PDF contains numerous links, many pointing to compromised or disposable domains, indicative of a link farm used for phishing or malware distribution. The ML classifier and ClamAV detection strongly suggest malicious intent. The document body is heavily obfuscated and unreadable, providing no direct content clues, but the heuristic firings clearly point to malicious link aggregation.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9893

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://bunny888.com/ckfinder/userfiles/files/52968160777.pdf In PDF document text
    • http://ozgu-yapi.com/firma/files/pamafumegewesemogenaxi.pdfIn PDF document text
    • https://egyiksem.hu/uploads/file/76333176720.pdfIn PDF document text
    • https://personalloan2u.com/wp-content/plugins/super-forms/uploads/php/files/fa70c455158554e595205352845f4d66/tiwagawadonukupeviwodu.pdfIn PDF document text
    • https://antoinepanau.com/wp-content/plugins/super-forms/uploads/php/files/7d82fe7d6f4a5c1cc82c7bd02752704e/21008607135.pdfIn PDF document text
    • http://tw-tms.com/uploadpic/xw/files/vejigixufido.pdfIn PDF document text
    • http://egitara.com/upfiles/files/51035908506.pdfIn PDF document text
    • http://www.mearesandassociatesllc.com/siteuploads/editorimg/file/1660625428.pdfIn PDF document text
    • http://bipaf.org/2009_home/upload/editor/file/59362696637.pdfIn PDF document text
    • http://ptaki.info/imgekoprojekty/files/45442768530.pdfIn PDF document text
    • http://www.oomedia.com.tw/ckfinder/userfiles/files/9605185071.pdfIn PDF document text
    • https://www.cylinder96.ru/admin/ckfinder/userfiles/files/tatuwoviju.pdfIn PDF document text
    • http://shopgraeagle.com/ckeditor/uploads/files/20805332732.pdfIn PDF document text
    • http://trivio.it/userfiles/files/90277655567.pdfIn PDF document text
    • https://eduinfinite.com/wp-content/plugins/super-forms/uploads/php/files/a461e6d49c6203e4e958b902f06e9d64/21819978477.pdfIn PDF document text
    • http://dreiseengrundschule.de/files/494384860.pdfIn PDF document text
    • http://nhasachthunam.com/upload/files/66820909707.pdfIn PDF document text
    • http://www.ddd-iasi.ro/wp-content/plugins/formcraft/file-upload/server/content/files/161514eb00a042---95115692228.pdfIn PDF document text
    • http://www.sg-callenberg.de/wp-content/plugins/formcraft/file-upload/server/content/files/16146182022374---43096624861.pdfIn PDF document text
    • https://euro-m.si/web/dokumenti/file/13118288140.pdfIn PDF document text
    • https://mma-montessori.com/admin/ckfinder/userfiles/files/60456588217.pdfIn PDF document text
    • http://lanaecoloridabruzzo.it/userfiles/file/fexejez.pdfIn PDF document text
    • https://bettenbaehren.de/wp-content/plugins/formcraft/file-upload/server/content/files/16141bb4fe798e---22025309790.pdfIn PDF document text
    • http://kibunajcc.com/ckfinder/userfiles/files/88664241139.pdfIn PDF document text
    • http://studionegro.net/userfiles/files/wajegokebitonemagosax.pdfIn PDF document text
    • http://andrelandberg.com/userfiles/file/xumifidufu.pdfIn PDF document text
    • https://feedproxy.google.com/~r/Uplcv/~3/6naE_Nh8_CY/uplcv?utm_term=android+astronomy+appsPDF 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_off0000b1f9.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xB1F9 10472 bytes
SHA-256: f0f33500a10e7b4f7d58ad2de1a6c956c052010ca2240a138bb5d3b3c29ffc55
font_01_sfnt_off0000c9bf.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xC9BF 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
font_02_sfnt_off0000e1d1.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xE1D1 15668 bytes
SHA-256: b15ac1915ae11fce8f8ba8d0066c1cd09898f29e558e2931d1b800432f967d5c