Malicious PDF — malware analysis report

Static analysis result for SHA-256 4331cd9dd3e19c24…

MALICIOUS

PDF

80.5 KB Created: 2021-09-18 07:09:49 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-11-24
MD5: 26452638a37e23c0cbc7bfbf663af1a3 SHA-1: 7c5e02e8696c7de9737af9cc9a80dcc9240874d1 SHA-256: 4331cd9dd3e19c2429e751c23bd6ac0c12abe0a2668fb23d627b27dd05a92497
126 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment

The PDF contains numerous embedded URLs, many of which are associated with link farms and disposable hosting, indicating a phishing or malware distribution attempt. The ML classifier and ClamAV detection strongly suggest malicious intent. While no scripts were directly extracted, the nature of the embedded URLs and the heuristic firings point towards a malicious document designed to redirect users to harmful sites.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9960

Heuristics 5

  • ClamAV: Pdf.Phishing.Trojan-d2568dad23a94d95-d2568dad23a94d95-10044375-0 critical CLAMAV_DETECTION
    ClamAV detected this file as malware: Pdf.Phishing.Trojan-d2568dad23a94d95-d2568dad23a94d95-10044375-0
  • 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://huntic.ru/uplcv?utm_term=adblock+chrome+ipad+pro PDF link annotation
    • https://sportyou.fr/ckfinder/userfiles/files/17911390897.pdfIn PDF document text
    • http://votava2.altrodesign.eu/ckfinder/userfiles/files/15157706285.pdfIn PDF document text
    • https://85097781.com/upload/files/gagapesorapus.pdfIn PDF document text
    • https://butzbacher.turnpoint.jo/app/webroot/upload/files/suvugapaj.pdfIn PDF document text
    • http://mutitar.com/user_img/files/49923216263.pdfIn PDF document text
    • https://airxps.com/userfiles/files/vapatotisawojubidebeg.pdfIn PDF document text
    • http://mofrantech.com/userfiles/file/dasabimexiwatel.pdfIn PDF document text
    • http://ziepniekkalns.lv/wp-content/plugins/formcraft/file-upload/server/content/files/16142c1e96e6c6---kofawezepinugepaniza.pdfIn PDF document text
    • https://napraforgohotel.hu/upload/file/wiwemufilixok.pdfIn PDF document text
    • http://strap.sk/uploads/file/kojozobexulonixigos.pdfIn PDF document text
    • http://btsoft.vn/uploads/files/13622478180.pdfIn PDF document text
    • http://brilspa.ro/userfiles/file///44350827751.pdfIn PDF document text
    • http://ttfi.org/app/webroot/userfiles/file/75311802005.pdfIn PDF document text
    • http://www.fullertherapy.com/wp-content/plugins/formcraft/file-upload/server/content/files/161450d207f6ce---84932268527.pdfIn PDF document text
    • http://sieuthimaynhapkhau.com/upload/files/nemamefutemolufegagimem.pdfIn PDF document text
    • http://newgrids.com/userfiles/file/zabijevudukutevakoxo.pdfIn PDF document text
    • https://saunadlaciebie.pl/userfiles/file/babogezumunozuxuju.pdfIn PDF document text
    • http://hoshitorionline.com/uploads/files/38873174277.pdfIn PDF document text
    • http://libron.pl/fckupload/assets/file/ketukul.pdfIn PDF document text
    • http://teewer.mn/ckfinder/userfiles/files/puzorebomipepuxufogowaxi.pdfIn PDF document text
    • https://panegovernance.com/ourprojects/chowki/UserFiles/file/66083729323.pdfIn PDF document text
    • https://ourlady-schools2.com/userfiles/files/69151295302.pdfIn PDF document text
    • https://stiglic.sk/userfiles/file/raxijor.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_off0000d4e1.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xD4E1 10624 bytes
SHA-256: fb1096c571b34144154c1f717300f52bd21e92c8a156cbb7cf013bde743ec675
font_01_sfnt_off0000ece5.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xECE5 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
font_02_sfnt_off000104f7.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x104F7 18192 bytes
SHA-256: 1e39ee16f4ff1709e7203f1a3286f09a3f221067226c242929bc48bf3e950199