Malicious PDF — malware analysis report

Static analysis result for SHA-256 7d534df5d4773c57…

MALICIOUS

PDF

87.4 KB Created: 2021-09-11 11:03:56 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-10-24
MD5: 2c65e190b40c11a9447aa8e7246aa89a SHA-1: 1dd36884caa995e849a4a39528cda3c6bb79bcaf SHA-256: 7d534df5d4773c5707d14cf0ac8eb19f5ac3480c9897ec7d17ae0816e8a9e37c
126 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment T1203 Exploitation for Client Execution

The file was detected as malicious by ML classifiers and ClamAV, indicating a high likelihood of malicious intent. It contains numerous external URIs and is identified as a link farm hosted on disposable domains, suggesting a phishing or malware distribution lure. The PDF structure itself does not contain readable content, but the presence of multiple external links points to an attack pattern focused on redirecting users to potentially harmful websites.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9980

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://synerhu.ru/uplcv?utm_term=intel+wireless+display+android+app PDF link annotation
    • http://marcobernini.it/userfiles/files/vagenedulawofegu.pdfIn PDF document text
    • https://www.potterycommercials.co.uk/wp-content/plugins/formcraft/file-upload/server/content/files/1612ec290d4084---wivadobozatazeru.pdfIn PDF document text
    • http://reopen911.info/media/file/kagerafa.pdfIn PDF document text
    • https://stka.gr/ckfinder/userfiles/files/35520439894.pdfIn PDF document text
    • http://pantanalmsnews.com.br/ckfinder/userfiles/files/diroboxivibizatepizikojud.pdfIn PDF document text
    • http://zjqzzx.com/uploadfile/file/2021090621482073499.pdfIn PDF document text
    • http://travellerisland.com/files/25566762477.pdfIn PDF document text
    • https://123natura.com/stockages/files/dujakolurukugazuzamamum.pdfIn PDF document text
    • https://propbrains.com/wp-content/plugins/super-forms/uploads/php/files/8720b097de73c610fa20a1118f572f1f/zijomuwilifikel.pdfIn PDF document text
    • http://vakantie-noordlimburg.nl/ckfinder/userfiles/files/54187591527.pdfIn PDF document text
    • http://muntepa.com/userfiles/files/xugazepimizozojaparebap.pdfIn PDF document text
    • http://dansungsala.com/uploads/files/91387610802.pdfIn PDF document text
    • http://dichvugiayphep.net/hinhanh_fckeditor/file/zopenuzonolasegiwipekeji.pdfIn PDF document text
    • https://srccaa.bdbabymart.com/app/webroot/ckfinder/userfiles/files/57807620536.pdfIn PDF document text
    • https://rivieresoceanie.com/userfiles/file/kifuvigeta.pdfIn PDF document text
    • http://ymmicro.com/files/files/sebujubaxoj.pdfIn PDF document text
    • https://apskarota.org/userfiles/file/60463272894.pdfIn PDF document text
    • http://pasaru.com/upload/files/93763507179.pdfIn PDF document text
    • http://saothienemb.com/uploads/images/files/xajinafekumarobokiravu.pdfIn PDF document text
    • https://khoahoc.timviec365.com/picturesfiles/58866756570.pdfIn PDF document text
    • http://hart-metale.pl/gimnazjum/userfiles/file/pesolaf.pdfIn PDF document text
    • http://olimpic.hu/ckfinder/userfiles/files/dodexeju.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_off0000ea80.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xEA80 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
font_01_sfnt_off00010292.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x10292 20452 bytes
SHA-256: c23bedcfa0cb1de730c0d6bb39fb8e0f6b519427911295a67beff9c36460f6d9
font_02_sfnt_off00013814.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x13814 10536 bytes
SHA-256: f54fff1f217ab585cf391d1d200e2eb49149ba02a710be277459cdcaacd420bf