Malicious PDF — malware analysis report

Static analysis result for SHA-256 f0550a2d459db93c…

MALICIOUS

PDF

82.5 KB Created: 2021-09-20 16:54:34 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-11-23
MD5: 8fb5b086a32b7813355c61577be9e576 SHA-1: cd5b9e57230dfe03653bec0f8e5ac7ae2d90ecf1 SHA-256: f0550a2d459db93c8c6b432c0b478752942647591e6a29d8591606453e0ef78d
156 Risk Score

Malware Insights

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

The PDF was flagged by ClamAV as Pdf.Phishing.Trojan and an ML classifier indicated a high probability of maliciousness. Several heuristics identified the PDF as a link farm, with many URLs pointing to compromised CMS upload directories or disposable hosting. The embedded URLs suggest an attempt to direct users to external, potentially malicious, content.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9955

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://nhatrangpalace.vn/app/webroot/upload/files/fabezetinadirege.pdf In PDF document text
    • https://mattress-leader.com/media/mezuwefeli.pdfIn PDF document text
    • http://kmkonsult.cz/userfiles/file/falokezixefajidupaxamep.pdfIn PDF document text
    • http://inciboya.com/resimler/site/files/98904152692.pdfIn PDF document text
    • http://fazendasaojudastadeu.net/fotosempresa/files/nowavavejelat.pdfIn PDF document text
    • https://www.frankcapassoandsons.com/wp-content/plugins/formcraft/file-upload/server/content/files/1613ff15a31f80---98254426389.pdfIn PDF document text
    • https://stratasphere.online/userfiles/file/45967580474.pdfIn PDF document text
    • http://3handseg.com/wp-content/plugins/formcraft/file-upload/server/content/files/161451d89dcdad---jagarigaxijuvaxanugew.pdfIn PDF document text
    • https://people11people.com/uploads/File/1089377143.pdfIn PDF document text
    • http://xn--3bsx3iw22bmot.com/filespath/files/20210915105948.pdfIn PDF document text
    • https://lmbri.com/WYSIWYGImage/file/22434271323.pdfIn PDF document text
    • http://cablexconsulting.com/Upload/file/6936231304.pdfIn PDF document text
    • http://gemwishrs.com/ckfinder/stones/files/mepebaroru.pdfIn PDF document text
    • http://inarchengineering.it/userfiles/files/wajubozafawivut.pdfIn PDF document text
    • http://quatanggiabao.com/images/uploads/files/tivebezasewagofuwetowa.pdfIn PDF document text
    • http://thoitrangvabaoho.com/Images_upload/files/13850503922.pdfIn PDF document text
    • http://kwik-it.ru/wp-content/plugins/formcraft/file-upload/server/content/files/1614862b7a5c00---xibodumiguzi.pdfIn PDF document text
    • http://findmealocalpainter.com/insurazon/admin/userfiles/file/gefuzijavegikijum.pdfIn PDF document text
    • https://doitoutdoorz.com/file/wjuwUqwj9LRwkGzF.pdfIn PDF document text
    • http://farashimirooz.com/files/6310621084.pdfIn PDF document text
    • http://www.marcelasemper.com/wp-content/plugins/formcraft/file-upload/server/content/files/16139a52ae783f---jabojifokowarasurasi.pdfIn PDF document text
    • https://namhunglogistic.vn/site/files/54277496575.pdfIn PDF document text
    • http://www.loicadesacavem.pt/wp-content/plugins/formcraft/file-upload/server/content/files/1613cd7c4f0dd4---65249752573.pdfIn PDF document text
    • http://powercleanperu.com/cms_powerclean_2015/sgi_userfiles/userfiles/files/4911697249.pdfIn PDF document text
    • https://feedproxy.google.com/~r/skout/mBVl/~3/fzgW7-mxBc0/uplcv?utm_term=the+seven+deadly+sins+season+3+episode+1PDF 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_off0000da60.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xDA60 19180 bytes
SHA-256: 287b3b02583be17c230cea10e192c254d5307c6158438746860966c357265002
font_01_sfnt_off00010bbe.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x10BBE 10656 bytes
SHA-256: 64b07d774c94016f21e59b204acf5b57903dbbefc6450fd187ff3f6ef5264913
font_02_sfnt_off0001242b.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x1242B 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1