Malicious PDF — malware analysis report

Static analysis result for SHA-256 88741efe3e4a6c20…

MALICIOUS

PDF

78.3 KB Created: 2021-09-18 16:43:33 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-10-12
MD5: f1837b920110479616574ce58af5156c SHA-1: 22ce7c5294b050ff5c02760c8d1ff71c78933000 SHA-256: 88741efe3e4a6c2011c8a16861acb6c1ff29bbbde5dd286b415274bba68ba27c
156 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment T1204.002 Malicious Link

The file was detected as malicious by ClamAV and an ML classifier, indicating a high likelihood of malicious intent. Heuristics identified it as a link farm, with multiple URLs pointing to PDF files hosted on potentially compromised websites. The presence of these links suggests the document is designed to lure users to external resources, likely for phishing or to download further malicious content.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9975

Heuristics 6

  • ClamAV: Pdf.Phishing.Trojan-d2568dad23a94d95-d2568dad23a94d95-10044375-0 critical CLAMAV_DETECTION
    ClamAV detected this file as malware: Pdf.Phishing.Trojan-d2568dad23a94d95-d2568dad23a94d95-10044375-0
  • 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 http://queensparkview.com/image/upload/File/bosukiguxopi.pdf In PDF document text
    • http://revize-elektro.info/UserFiles/File/63471732842.pdfIn PDF document text
    • https://hotelharmika.com/assets/userfiles/files/57048550222.pdfIn PDF document text
    • http://novena99.com/uploads/files/202109050054075284.pdfIn PDF document text
    • http://memsports.com.br/admin/libs/ckeditor/ckfinder/files/mapesedazazosora.pdfIn PDF document text
    • http://dharmapuridiocese.com/svnprojects/DHD/Source/images/files/2511637717.pdfIn PDF document text
    • http://sherwoodonionfestival.com/ckfinder/userfiles/files/44015697016.pdfIn PDF document text
    • https://www.energetisch-therapeut-estie.nl/wp-content/plugins/formcraft/file-upload/server/content/files/1613609e68a098---baxuzimu.pdfIn PDF document text
    • https://bienenaktuell.com/sites/bienenaktuell.com/files/file/60262252743.pdfIn PDF document text
    • http://aquamedia.cn/ckfinder/userfiles/files/44095940076.pdfIn PDF document text
    • http://fornacedelia.it/userfiles/files/14884822085.pdfIn PDF document text
    • http://www.louisianarebarcontractor.com/editorimg/file/3207326686.pdfIn PDF document text
    • https://walkandsmile.com/userfiles/file/jizusafukumepanibofenaje.pdfIn PDF document text
    • http://loca-granderoue-montaletang.com/ckfinder/userfiles/files/fixakumuvaj.pdfIn PDF document text
    • http://baschin-heizung.com/meineBilderAlbertGrundschule/file/35380784124.pdfIn PDF document text
    • http://yourmoneyyourbank.com/uploads/File/gipalisakuwodesamutaj.pdfIn PDF document text
    • http://mmbc.cz/_data/user_files/file/15634933666.pdfIn PDF document text
    • http://sethhukumchandschool.com/userfiles/file/6900518189.pdfIn PDF document text
    • http://www.combatsim.eu/wp-content/plugins/formcraft/file-upload/server/content/files/16135b3e5d2fd8---feralininomavukizi.pdfIn PDF document text
    • http://www.ortodonciaelisafarache.com/ckfinder/userfiles/files/48373467526.pdfIn PDF document text
    • http://milwaukee.center/userfiles/file/91152063370.pdfIn PDF document text
    • http://asiavent.com/UserFiles/file///jotuzupamuwarok.pdfIn PDF document text
    • https://rmissio.pl/wp-content/plugins/formcraft/file-upload/server/content/files/1614564a19b9a5---76977314134.pdfIn PDF document text
    • https://siangyun.com/upfiles/editor/files/fesuwi.pdfIn PDF document text
    • http://bjsddesign.com/filespath/files/20210910125410.pdfIn PDF document text
    • https://feedproxy.google.com/~r/1eyvgo/aqOO/~3/PmAiG5ZyT-k/uplcv?utm_term=mobile+apk+onlinePDF link annotation
    • 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_off0000d04f.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xD04F 17144 bytes
SHA-256: 48d53cd246223493685319b231a5a719b369ffe9b03121dcc544a44fc63e4cb3
font_01_sfnt_off0000fd4a.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xFD4A 10104 bytes
SHA-256: cf6c64a43684087d766eb7ae46435ba02b648f39b3e38933f8628f2adf1fd3a1
font_02_sfnt_off000113a3.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x113A3 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1