Malicious PDF — malware analysis report

Static analysis result for SHA-256 3916d51c5e448d61…

MALICIOUS

PDF

69.2 KB Created: 2021-10-03 16:31:39 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-11-24
MD5: dee48d761c399058a61e7b670fd09570 SHA-1: cebb6d2ff3ed713a50f37dadb9d9d78a5107fef1 SHA-256: 3916d51c5e448d611a780a957d0a67b0fb4bbe0dcac7dc3abd8bc73d1730ab99
126 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment

The PDF contains numerous external URIs and is flagged as a link farm on disposable hosting, indicating a phishing or redirection scheme. The ML classifier and ClamAV detection strongly suggest malicious intent. Although no scripts were explicitly extracted, the PDF structure and external links point towards a common attack pattern of luring users to malicious sites, likely for credential harvesting or further payload delivery.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9965

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://archism.ru/uplcv?utm_term=maple+cash+and+carry PDF link annotation
    • http://cftckr.marketsearching.com/upload/files/makagiwagumevigunobujid.pdfIn PDF document text
    • http://kartinatv.org/uploads/files/42357984238.pdfIn PDF document text
    • http://talk200.com/admin/admin/uploadfiles/file/rivowuderixekagabuvuritid.pdfIn PDF document text
    • http://lindendirect.com/ckfinder/userfiles/files/baloruloxopuvavofad.pdfIn PDF document text
    • https://siam-royal-view.ru/data/files/11982917389.pdfIn PDF document text
    • http://maketmaster.ru/admin/ckfinder/userfiles/files/linavi.pdfIn PDF document text
    • https://nacionalequipamentos.com/ckeditor/uploads/files/21343202892.pdfIn PDF document text
    • http://phunphu.com/userfiles/file/29184591701.pdfIn PDF document text
    • https://innovativallatgyogyszer.hu/fileok/file/lapixage.pdfIn PDF document text
    • https://10glazsikeyrosa.ru/file/45028363609.pdfIn PDF document text
    • https://www.parquesanalbertohurtado.cl/ckfinder/userfiles/files/20205197819.pdfIn PDF document text
    • https://dazzlin.co.uk/wp-content/plugins/super-forms/uploads/php/files/2282cdbf16a008b8dc01bfbc0ee9ad40/34912229292.pdfIn PDF document text
    • http://gasthaus-steinkirchen.de/img/editor/file/xitoj.pdfIn PDF document text
    • http://gu-bo.cn/uploads/files/35303612234.pdfIn PDF document text
    • https://hoffmanowska.pl/wp-content/plugins/formcraft/file-upload/server/content/files/16140cb78f4014---7376218292.pdfIn PDF document text
    • http://fleshlight-tw.com/userfiles/file/ferepexerutijijefodunimo.pdfIn PDF document text
    • http://heichapuzi.com/uploadfile/file/xebezotarapotimatofa.pdfIn PDF document text
    • http://swapnakoodu.com/fck_uploads/file/rolugulorese.pdfIn PDF document text
    • http://hodoan.net/userfiles/file/resokonare.pdfIn PDF document text
    • http://www.trisad.kz/ckfinder/userfiles/files/30725812283.pdfIn PDF document text
    • http://techsystem.gr/data/uploads/ckeditor/files/81700572755.pdfIn PDF document text
    • http://gtlitalia.com/userfiles/files/pesulakadutupinodugi.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_off0000ad74.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xAD74 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
font_01_sfnt_off0000c58b.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xC58B 10408 bytes
SHA-256: a77e93d670b1cca7cea0b7250549f04e855e924bf633f55113d1e70fd736e262
font_02_sfnt_off0000dd14.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xDD14 16808 bytes
SHA-256: c984ae8859386ec0447f47ef45015710b017d1eee310c59371c3b16549e849f0