Malicious PDF — malware analysis report

Static analysis result for SHA-256 db6b34cc45062239…

MALICIOUS

PDF

71.3 KB Created: 2021-10-10 18:32:18 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-11-22
MD5: 16b4b439694591dffec985e8e2290818 SHA-1: 1f56ec9ed1dec849bdb5613ddfcb28db6d3214cd SHA-256: db6b34cc450622395b9c46cc865cc21e37ad287f361a716bef365b7dc1a3ce31
126 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment

The PDF file was flagged by a machine learning classifier and ClamAV as malicious, specifically identified as a phishing trojan. The heuristic analysis revealed it functions as a link farm, containing numerous links to potentially malicious PDF files hosted on various domains. While no scripts were explicitly extracted, the nature of the embedded links suggests an attempt to redirect users to phishing sites or download further malicious content.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9947

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://christembassybarking.org/wp-content/plugins/super-forms/uploads/php/files/50ab28ddd4de714697d9b8306c78fdda/7148600074.pdf In PDF document text
    • http://marktoby.com/akram/know_news/admin/userfiles/file/zovexowumina.pdfIn PDF document text
    • http://voszveszprem.hu/_user/file/komigolik.pdfIn PDF document text
    • https://xn--psg-9lac.hu/files/files/55468171287.pdfIn PDF document text
    • http://pincailight.com/zk/UploadFile/file/2021100101292873499.pdfIn PDF document text
    • https://vnnc.vn/img-hdmedia/files/41611260562.pdfIn PDF document text
    • https://quanghuydulich.vn/img_duhoc/files/22420733620.pdfIn PDF document text
    • http://pawsandtiaras.com/ckfinder/userfiles/files/zalisofupokojoso.pdfIn PDF document text
    • http://copy-office.it/userfiles/file/86985635742.pdfIn PDF document text
    • http://cmuniontravel.com/userfiles/file/disarorigavadu.pdfIn PDF document text
    • http://webinaris.org/ckfinder/userfiles/publics/files/susivujalavef.pdfIn PDF document text
    • https://biorenta.lt/ckfinder/userfiles/files/ragavagegojevuz.pdfIn PDF document text
    • https://scalping.ir/data/files/file/lemitatiniwafogej.pdfIn PDF document text
    • http://marsalanoleggio.it/userfiles/files/fasaxugux.pdfIn PDF document text
    • https://drmiamiconnect.com/wp-content/plugins/super-forms/uploads/php/files/2c3232c0851e590120fa7844f3c62878/fowomovekazovuzel.pdfIn PDF document text
    • http://assytekservizi.com/userfiles/files/16320532436.pdfIn PDF document text
    • https://rimi.sk/userfiles/file/10062292822.pdfIn PDF document text
    • http://krakowska98.com/zdjecia/fck/file/zovusuwinanusikirunosaga.pdfIn PDF document text
    • http://smepil.com/ckeditor/userfiles/files/65730445114.pdfIn PDF document text
    • http://xn----8sbfeahwarn6ac1adp3fb2p.xn--p1ai/userfiles/file/91534544684.pdfIn PDF document text
    • https://kratky.eu/files/file/jajuwekodusebok.pdfIn PDF document text
    • http://colorfusion.us/admin/images/file/37060233739.pdfIn PDF document text
    • https://agriplan-rs.com/dados/ckfinder/files/44930396556.pdfIn PDF document text
    • http://opusbiz.kr/data/editor/file/13725653206140413f1a4e5.pdfIn PDF document text
    • https://feedproxy.google.com/~r/Uplcv/~3/S30rS-6n6vg/uplcv?utm_term=scale+up+partnersPDF link annotation
    • http://elezioni2014.gds.it/userfiles/file/45706118116.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_off0000b618.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xB618 10328 bytes
SHA-256: 8b9ed842ec502e865cfe76f305e83731f3829f00f9450ca7d96bca48fd2dedff
font_01_sfnt_off0000cd84.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xCD84 16664 bytes
SHA-256: 52bbaaad94a049c73d58a267614e226b197ba8c579746a4f57d4b8e2b7d736d7
font_02_sfnt_off0000f809.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xF809 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1