Malicious PDF — malware analysis report

Static analysis result for SHA-256 27a8c05892b5a876…

MALICIOUS

PDF

67.8 KB Created: 2021-09-20 10:42:01 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-10-26
MD5: a40ca3d20208d187c499336b3d133c50 SHA-1: ca1d7c3b6f5f58ac7389833b3cdf77557abd6d9a SHA-256: 27a8c05892b5a876ed8879c5ba07c0ec1137f07e18f377a411dc81e1eb4f452a
126 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment

The PDF contains numerous embedded URLs, with a high heuristic indicating it functions as a link farm on disposable hosting. The ML classifier and ClamAV detection strongly suggest malicious intent, likely for phishing or distributing further malware. Although no scripts were explicitly extracted, the PDF structure and URL distribution are indicative of a malicious document, potentially leveraging embedded JavaScript for malicious actions.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9952

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 http://ndt-tl.ru/upload/file/64650301163.pdf In PDF document text
    • https://robustbrakes.com/administrator/imagetemp/file/mepemesepenepomi.pdfIn PDF document text
    • http://xn--80aer5aza.xn---42-5cdakyymnnb9ake1az.xn--p1ai/ckfinder/userfiles/files/35606088508.pdfIn PDF document text
    • http://hansungid.com/userfiles/file/38493124940.pdfIn PDF document text
    • https://marblo.com/app/webroot/img/files/62447158214.pdfIn PDF document text
    • http://christ-china.com/filespath/files/20210906092545.pdfIn PDF document text
    • https://athensviptour.com/wp-content/plugins/super-forms/uploads/php/files/29ab067d5453c22ce32def18425dbaed/57118240717.pdfIn PDF document text
    • http://hanlacsclub.com/ckupload/files/witewesawiten.pdfIn PDF document text
    • https://www.q-jin.ne.jp/ckfinder/userfiles/files/bakob.pdfIn PDF document text
    • https://livre-d-art.com/ckfinder/userfiles/files/gipitosixivi.pdfIn PDF document text
    • https://alamansyria.com/userfiles/file/wewuxonovigaje.pdfIn PDF document text
    • http://kccmaul.com/files/files/dutakatipozexafejasujokun.pdfIn PDF document text
    • http://trip-sale.ru/userfiles/file/sazilopivovof.pdfIn PDF document text
    • https://degardo.hollandpazsit.hu/ckfinder/userfiles/files/mewokigoxizaxunigo.pdfIn PDF document text
    • https://lenaoyunlar.com/calisma2/files/uploads/31578717798.pdfIn PDF document text
    • https://zahrek.com/userfiles/file/11798035502.pdfIn PDF document text
    • http://scouttautomotive.com/editor_uploads/system/files/wojumobeku.pdfIn PDF document text
    • http://tagsu.com/attachments/fckattachments/file/tupemuzugumibajomifuz.pdfIn PDF document text
    • http://drcleancenter.com/uploads/files/202109161803027605.pdfIn PDF document text
    • http://chaodontuonglai.vn/uploads/ck_upload/files/94472680653.pdfIn PDF document text
    • http://aire-limpio.com/img/editor/file/xoruwoxojo.pdfIn PDF document text
    • http://evo-models.com/uploads/userfiles/files/48536005779.pdfIn PDF document text
    • https://abcelectricalonlineshop.brilliantwebtech.com/userfiles/files/17301805701.pdfIn PDF document text
    • https://feedproxy.google.com/~r/skout/mBVl/~3/A3Ryygt5BCM/uplcv?utm_term=flash+download+androidPDF link annotation
    • http://abcs.umontreal.ca/upload/files/60293840131.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_off0000af46.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xAF46 14360 bytes
SHA-256: c27ad8f642a1c69b95dd3f8d554e80a303f328443f7fae43563ef3ad3667e687
font_01_sfnt_off0000d35f.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xD35F 10176 bytes
SHA-256: bff40331cb149d88d56035f71abc5101189f9ef625095feda813afd3bbf954a7
font_02_sfnt_off0000ea0b.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xEA0B 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1