Malicious PDF — malware analysis report

Static analysis result for SHA-256 1626d4bf1bf5766a…

MALICIOUS

PDF

72.1 KB Created: 2021-09-14 04:02:40 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-10-05
MD5: 839f893bb607399ac43c722383985a0d SHA-1: fe41e48444ffdc6196d6f437ec247a790e54f19b SHA-256: 1626d4bf1bf5766a59df733fd43063d25ccb405465f51df401f7470a96624c51
156 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment

The PDF contains numerous external links, many pointing to compromised websites or disposable hosting, suggesting a link farm designed to redirect users. The ML classifier and ClamAV detection strongly indicate malicious intent, likely for phishing or distributing further malware. No scripts were extracted, but the heuristic firings and URL analysis point to a common pattern of using documents to redirect users to malicious sites.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9956

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 https://smidgel.ru/uplcv?utm_term=tuck+everlasting+study+guide+pdf PDF link annotation
    • http://rovitek.com/userfiles/file/20285533686.pdfIn PDF document text
    • http://crm333.com/documentos/file/parurusigos.pdfIn PDF document text
    • http://tydafa.com/dafa/uploadfiles/20210913215416.pdfIn PDF document text
    • https://pakistanchristiancongress.org/userfiles/file/54542250350.pdfIn PDF document text
    • http://nuyewrecruitment.com/wp-content/plugins/super-forms/uploads/php/files/a3031ccf16b9d0c02b69cea9caccd8ac/41697883677.pdfIn PDF document text
    • http://gfb.it/upload/fck/file/79527331302.pdfIn PDF document text
    • http://szm.hu/userfiles/file/xugudizopama.pdfIn PDF document text
    • http://misosmile.com/upload/editor/files/9279660999.pdfIn PDF document text
    • http://shanghaiqingchen.com/upload/files/1997658222.pdfIn PDF document text
    • http://gasasosong.com/upload/fckeditor/file/luwesewonesedekatigexared.pdfIn PDF document text
    • http://pedraferro.com/files/files/19096109598.pdfIn PDF document text
    • http://ping-property.com/user_img/files/22243676092.pdfIn PDF document text
    • http://asesorialuishervas.com/wp-content/plugins/formcraft/file-upload/server/content/files/1613fedfbe2425---pibedunejewa.pdfIn PDF document text
    • https://giasidaily.com/uploads/userfiles/file/lezunebazuvesijufizaxisep.pdfIn PDF document text
    • http://cartopack.com/Images/file/99777716139.pdfIn PDF document text
    • http://intranet.uts.edu.co/portal/app/ckfinder/userfiles/files/zemixagalanewiwes.pdfIn PDF document text
    • https://www.champagne-cornevin.fr/ckfinder/userfiles/files/54150822933.pdfIn PDF document text
    • https://www.grandiosa.is/wp-content/plugins/super-forms/uploads/php/files/tua72ea8q14avru6v8vms5ltj4/fazufebaw.pdfIn PDF document text
    • http://ilink.pl/userfiles/file/nuvevorexuwibuxisopezujo.pdfIn PDF document text
    • https://motionslam.com/wp-content/plugins/super-forms/uploads/php/files/7cc451c883caa143ca4eb00518a856cf/zosevibepolevofed.pdfIn PDF document text
    • http://xn----7sbezcba9a5aggb3j.xn--p1ai/ckfinder/userfiles/files/62470048729.pdfIn PDF document text
    • http://cl-metalparts.com/d/files/40789589665.pdfIn PDF document text
    • https://haisanquangninh.org/data/dulieu/files/vitomizugajifitifiwu.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_off0000b98f.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xB98F 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
font_01_sfnt_off0000d1a6.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xD1A6 11012 bytes
SHA-256: b9a2b7c15c8f9790658595c6c43f997d85facb56d06a911afaac4c65fa9a989d
font_02_sfnt_off0000eb38.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xEB38 15416 bytes
SHA-256: 29f3db237d29c73d653b3a89bda6b580bbf8aa2bcb442a6c49196319e22a490b