Malicious PDF — malware analysis report

Static analysis result for SHA-256 82359f80cf69769d…

MALICIOUS

PDF

86.0 KB Created: 2021-09-15 20:15:49 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-10-14
MD5: 36cf7204a0808aa7be3fb49dd5160078 SHA-1: 58c0709d42fd86a05cf5fa208d3ddeb90c040a53 SHA-256: 82359f80cf69769d23d558fd1fa4a2768f1a2e9b3725b366169a14a12db6703a
126 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment

The PDF file was detected as malicious by ClamAV and an ML classifier, indicating a high likelihood of malicious intent. Heuristics identified it as a link farm on disposable hosting, with numerous external URIs pointing to potentially malicious sites. The document body is heavily obfuscated, but the presence of embedded URLs and the link farm heuristic suggest the primary goal is to redirect users to external, potentially malicious content, likely for phishing or malware distribution.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9980

Heuristics 5

  • ClamAV: Pdf.Phishing.Trojan-d2528dad23a95d95-d2528dad23a95d95-10044376-0 critical CLAMAV_DETECTION
    ClamAV detected this file as malware: Pdf.Phishing.Trojan-d2528dad23a95d95-d2528dad23a95d95-10044376-0
  • 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://philabc.ru/uplcv?utm_term=white+christmas+3d+live+wallpaper+and+screensaver PDF link annotation
    • http://d-innovation.com/upload/files/19970821416.pdfIn PDF document text
    • http://xn--rssx31a7tec6p.com/upload/userfiles/files/20210906110157.pdfIn PDF document text
    • http://holidayservicemarsala.it/userfiles/files/vubuvuketarixufigef.pdfIn PDF document text
    • http://quiltingacademy.com/fckeditor/userfiles/file/7497148680.pdfIn PDF document text
    • https://ladulceseguros.ar/noticias/fckeditor/file/43596235944.pdfIn PDF document text
    • https://treasurehunterdetectors.com/ckfinder/userfiles/files/sumularubozade.pdfIn PDF document text
    • http://giprozdraw.ru/ckfinder/userfiles/files/2812176376.pdfIn PDF document text
    • http://laboratorioshamalab.com/userfiles/file/63775850978.pdfIn PDF document text
    • http://kleinschaden-expert.de/userfiles/file/temapameluwonavozafon.pdfIn PDF document text
    • https://pelicanfinancialnetwork.com/ckfinder/userfiles/files/38856789005.pdfIn PDF document text
    • http://www.instalacionescueto.com/nueva/ckfinder/userfiles/files/xejezobuxuso.pdfIn PDF document text
    • http://eugensa.lt/app/webroot/uploads/userfiles/files/bigukatuduwer.pdfIn PDF document text
    • https://lrsinc.co/userfiles/file/nuvubabemizaviwiruwi.pdfIn PDF document text
    • http://inewbus.com/wp-content/plugins/super-forms/uploads/php/files/dbhktco4520jdrgsjtk0p5pkv4/14652802996.pdfIn PDF document text
    • http://bluebiz.kr/userData/board/file/15778072964.pdfIn PDF document text
    • https://thietkewebseo.com/webroot/img/files/bujobugibatezepivaj.pdfIn PDF document text
    • http://www.yoko-ono.be/images/userfiles/file/7055179546.pdfIn PDF document text
    • https://innovativallatgyogyszer.hu/fileok/file/wezulasutoram.pdfIn PDF document text
    • http://matchedtubes.de/userfiles/file/72086157457.pdfIn PDF document text
    • https://sts-cct.com/app/webroot/userfiles/files/44208606467.pdfIn PDF document text
    • https://divetechmarine.com/contents/files/lixokugazejujezudejafow.pdfIn PDF document text
    • http://bacsiha.com/public/ckfinder/userfiles/files/44817523665.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_off0000ea0f.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xEA0F 18108 bytes
SHA-256: 3ec5574b61e8541fdff778c3da77d68e272ea61a1aa0f519e869de95e33a3f6a
font_01_sfnt_off000118ac.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x118AC 10976 bytes
SHA-256: bb673aab8d3540d1e7e17cbd5cd319e7bc6c04bc614f8f5880ed532ab0ee75fc
font_02_sfnt_off00013210.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x13210 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1