Malicious PDF — malware analysis report

Static analysis result for SHA-256 979b962bba2d1dcc…

MALICIOUS

PDF

80.6 KB Created: 2021-09-16 06:14:56 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-10-16
MD5: 54db9860efb4036e629e097a07435f27 SHA-1: 0f43579bcd595ba302724a4487c7f4beb90ce526 SHA-256: 979b962bba2d1dccbc22e023b2005339ff2da868249927442274aba245e80e46
96 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment

The PDF document contains numerous embedded URLs, many of which are part of link farms hosted on disposable or compromised domains, suggesting a distribution or phishing campaign. The ML classifier strongly indicated maliciousness, and the presence of multiple PDF-specific heuristics related to URI and link farm activity further supports this. No scripts were extracted, but the document's structure and embedded links are designed to redirect users to potentially harmful content.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9949

Heuristics 5

  • 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://irlanc.ru/uplcv?utm_term=harry+potter+and+the+deathly+hallows+book+pdf+free PDF link annotation
    • http://fskyok.com/uploadfile/files/pasopaxex.pdfIn PDF document text
    • http://botosani.ro/img/uploads/file/9166784212.pdfIn PDF document text
    • https://www.davidwoodpersonnel.com/wp-content/plugins/formcraft/file-upload/server/content/files/1613b531fb4534---tomukifa.pdfIn PDF document text
    • https://nhahangthanghuong.com/uploads/files/bexefumaxefesufogi.pdfIn PDF document text
    • http://winecellarkeeper.com/ckfinder/userfiles/files/79944567178.pdfIn PDF document text
    • http://startent.ru/SITE/files/editor/file/84295248728.pdfIn PDF document text
    • https://creationstationdance.com/wp-content/plugins/formcraft/file-upload/server/content/files/1613f30b82b7a6---35836396096.pdfIn PDF document text
    • http://bellamy.tw/uploads/files/202109151237456862.pdfIn PDF document text
    • http://sola-brothers.com/userfiles/file/76611249138.pdfIn PDF document text
    • http://pogotowienaukowe.com/Upload/file/1702695511.pdfIn PDF document text
    • http://gesundezellen.de/neu/userfiles/file/godutulinonon.pdfIn PDF document text
    • http://aolisenjiancai.com/data/files/27006061463.pdfIn PDF document text
    • http://strelnicebudejovice.cz/userfiles/file/jatijapawuwupixemowafabu.pdfIn PDF document text
    • https://kanat.com/upload/ckfinder/files/gebadosikejezatemoratij.pdfIn PDF document text
    • http://findusafranchise.com/files/files/80771022717.pdfIn PDF document text
    • https://perfecthospitals.org/ckfinder/userfiles/files/93829653749.pdfIn PDF document text
    • http://nanoservice.cz/upload/file/notodulamogoketiwujeza.pdfIn PDF document text
    • http://vivatbacchus.hu/files/file/32220090530.pdfIn PDF document text
    • http://homespakistan.net/magzine/uploadfiles/file/57044303789.pdfIn PDF document text
    • https://gs-hemeringen.de/ablage/userfiles/files/badefesutexipur.pdfIn PDF document text
    • http://www.uppld.org/wp-content/plugins/formcraft/file-upload/server/content/files/16141396ab7b85---90847567440.pdfIn PDF document text
    • http://tunesistudio.eu/userfiles/files/tagodasilizujakilakiz.pdfIn PDF document text
    • http://peaceinsrilanka.lk/userfiles/file/60077117951.pdfIn PDF document text
    • https://arvikabc.com/images/uploadedimages/file/91437141883.pdfIn PDF document text
    • http://hublihorse.com/uploads/userfiles/files/nuwam.pdfIn PDF document text
    • 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_off0000d76e.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xD76E 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
font_01_sfnt_off0000ef80.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xEF80 16996 bytes
SHA-256: ed16294dcb243df6b3431d6bb1e839473239cc95faa46512f3842a632f3367e9
font_02_sfnt_off00011b4c.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x11B4C 10924 bytes
SHA-256: cfd27b6ede7e64a2c9b9c962987e5a4faabf904a9786c231697c14eee226e1aa