Malicious PDF — malware analysis report

Static analysis result for SHA-256 a4daff6e1c739854…

MALICIOUS

PDF

75.6 KB Created: 2021-09-21 11:14:37 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-11-25
MD5: d39d9abc8411fb19c1d4913f8ea6fae3 SHA-1: 6ad82e86fbcf9ae25471030f016f51f51650afa5 SHA-256: a4daff6e1c7398541e2f7b72681496333f6bb7b7f3e767a481167957b90ec723
156 Risk Score

Malware Insights

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

The file was detected by ClamAV as Pdf.Phishing.Trojan and flagged by an ML classifier, indicating malicious intent. It contains numerous external links, many pointing to potentially compromised or disposable hosting, suggesting a link farm designed to redirect users. The PDF structure and embedded links are consistent with phishing or malware distribution campaigns.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9901

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://321eastern-thailand.com/userfiles/files/muxiwekibepavepega.pdf In PDF document text
    • http://kerekagy.hu/UserFiles/file/96144769890.pdfIn PDF document text
    • https://marupyara.com/fotos/userfiles/file/dotuguregonebinopugume.pdfIn PDF document text
    • https://ice-group.pl/userfiles/file/55101402342.pdfIn PDF document text
    • http://www.tm-africa.com/beta/public/uploads/cms_filescms_files/68975289929.pdfIn PDF document text
    • https://livstyle.ro/home/livstyle/public_html/uploads/files/lotoruneligogokawerulur.pdfIn PDF document text
    • http://atrsara.ir/resource/files/87734770984.pdfIn PDF document text
    • http://travelci.ru/ckfinder/userfiles/files/92603655944.pdfIn PDF document text
    • http://datong-travel.tw/upload/ckeditor/files/20210921111931.pdfIn PDF document text
    • https://rmissio.pl/wp-content/plugins/formcraft/file-upload/server/content/files/16138b49799376---80901424051.pdfIn PDF document text
    • https://adiwirawanbali.com/wp-content/plugins/super-forms/uploads/php/files/7d9a0430f917cfabb924cff17d25572b/jogosifafo.pdfIn PDF document text
    • http://rajskiewakacje.pl/userfiles/file/64039328515.pdfIn PDF document text
    • https://marblobath.com/app/webroot/img/files/70973435339.pdfIn PDF document text
    • http://jyotiacademicpress.org/uploads/file/risetafex.pdfIn PDF document text
    • http://officegate.biz/admin/fck_upload/file/tenigifog.pdfIn PDF document text
    • https://sg-design.top/wp-content/plugins/super-forms/uploads/php/files/ab95237c8e2082b2b9e9e8dee45786dd/gijobapa.pdfIn PDF document text
    • http://3234.us/data/attachment/file/xejifiduredufirujobib.pdfIn PDF document text
    • http://ks-system.co.uk/ckfinder/userfiles/files/rexowonivujofaloseperu.pdfIn PDF document text
    • http://wo-kop.pl/userfiles/file/lutavaxasezaxomaweta.pdfIn PDF document text
    • https://www.oalysa.cz/ckfinder/userfiles/files/guvafenipoworilela.pdfIn PDF document text
    • https://intekcanada.com/ckfinder/userfiles/files/53142858885.pdfIn PDF document text
    • http://fygl.net/uploads/file/101953379662.pdfIn PDF document text
    • http://sun-green.eu/ckfinder/userfiles/files/gomikipiva.pdfIn PDF document text
    • http://xn--80ackbssfuieecff0e8c.xn--p1ai/wp-content/plugins/super-forms/uploads/php/files/nbri0h84f61shecmrfojgq74q5/12602820615.pdfIn PDF document text
    • http://lexxyin.net/files/fckeditor/file/burerutokezopatufujuk.pdfIn PDF document text
    • http://lactopad.com/uploads/files/rinolapo.pdfIn PDF document text
    • http://xn--3bsx3iw22bmot.com/filespath/files/20210907023158.pdfIn PDF document text
    • https://feedproxy.google.com/~r/1eyvgo/aqOO/~3/S30rS-6n6vg/uplcv?utm_term=scheduler+in+android+examplePDF 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_off0000c33a.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xC33A 17024 bytes
SHA-256: f50a43f6e0b88637b790526b19db1b16d39ff12eafd6827e1080b5c45532fc22
font_01_sfnt_off0000efbc.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xEFBC 10788 bytes
SHA-256: 63054414a2c44c0ca5775dc754c94efac38b9b2d5b2638aea69d3bad5f0a341f
font_02_sfnt_off00010857.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x10857 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1