Malicious PDF — malware analysis report

Static analysis result for SHA-256 a8f55efd6410c899…

MALICIOUS

PDF

85.1 KB Created: 2021-09-14 13:12:28 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-10-11
MD5: 7a1ed8c39ba36d752f6b9165968984dc SHA-1: a3fa348f1213298f8ddd2718b1da4d991c08ae44 SHA-256: a8f55efd6410c899ed602e0ce7d661030b808cbb2679db39c5d9d45654be4229
156 Risk Score

Malware Insights

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

The PDF contains a large number of links pointing to various domains, many of which are identified as compromised CMS uploads or disposable hosting. The ML classifier and ClamAV detection strongly indicate malicious intent, likely to lure users to malicious sites. No scripts were extracted, and the document body was unreadable, but the link farm structure is a common phishing and malware distribution tactic.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9974

Heuristics 6

  • ClamAV: Pdf.Phishing.Trojan-d2528dad23a95d95-d2528dad23a95d95-10044376-0 critical CLAMAV_DETECTION
    ClamAV detected this file as malware: Pdf.Phishing.Trojan-d2528dad23a95d95-d2528dad23a95d95-10044376-0
  • 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://www.examnotice.in/uploads/files/bitubunufuwajop.pdf In PDF document text
    • https://5uempat.com/contents/files/nilikitavavilusizodivufeb.pdfIn PDF document text
    • http://ahcxdq.com/uploads/file/071255457439.pdfIn PDF document text
    • http://hondatayho.vn/images/ckeditor/files/89924928815.pdfIn PDF document text
    • http://inphilong.com/upload/files/niwujuwibawumumu.pdfIn PDF document text
    • https://hmjrgoldhockey.org/wp-content/plugins/super-forms/uploads/php/files/d70f4e82a99c8e9733fbf0b7d7845d55/71573674072.pdfIn PDF document text
    • http://www.giuseppe.ru/ckfinder/userfiles/files/bofejegozoxujola.pdfIn PDF document text
    • http://eros-arena.de/eros/userfiles/file/178488437.pdfIn PDF document text
    • http://sieckultury.pl/wp-content/plugins/super-forms/uploads/php/files/e8b8bc96f2d571a965c432f896d9ad78/42463595559.pdfIn PDF document text
    • https://mr-alian.com/upload/ckfinder/files/dixazejuwipopamosorefi.pdfIn PDF document text
    • http://www.anclupnapoli.it/userfiles/file/8779056246.pdfIn PDF document text
    • http://cathugo-yachts.de/res/wysiwyg/file/vosesemolevukanonogule.pdfIn PDF document text
    • http://culfordequestriancentre.org/UserFiles/file/6127676495.pdfIn PDF document text
    • https://yournew.site/wp-content/plugins/super-forms/uploads/php/files/l364i4jh494j873vim0b2mc8fs/rewilokorogitujubobelope.pdfIn PDF document text
    • https://hunglivet.com/uploads/files/202109040709563566.pdfIn PDF document text
    • http://macabrey-luthier.fr/data/Files/xopejutis.pdfIn PDF document text
    • https://husvagnsexpo.se/wp-content/plugins/formcraft/file-upload/server/content/files/1612ef81e4b4e5---81576374428.pdfIn PDF document text
    • http://www.1000ena.com/wp-content/plugins/formcraft/file-upload/server/content/files/16134ebaa22a75---5496909539.pdfIn PDF document text
    • http://www.siscbolivia.com/admin/uploaded/fck/file/11040159133.pdfIn PDF document text
    • http://kaplanpm.com/wp-content/plugins/formcraft/file-upload/server/content/files/16138cea3b1b00---68019412782.pdfIn PDF document text
    • http://shinserviceodi.ru/wp-content/plugins/super-forms/uploads/php/files/edf0e8ab63b90bf2e86e60d4d3d89507/vawadokosolixitigokenit.pdfIn PDF document text
    • http://daechienglishpark.com/ckfinder/userfiles/files/serubonada.pdfIn PDF document text
    • http://zoscm.zohukum.com/ckfinder/userfiles/files/47841615014.pdfIn PDF document text
    • https://vibangthuaphatlai.net/uploads/files/rodugomos.pdfIn PDF document text
    • https://lesrimaudieres.com/images/uploads/file/wudubujodelelopaxujoji.pdfIn PDF document text
    • https://feedproxy.google.com/~r/Uplcv/~3/FevRqgeaUVY/uplcv?utm_term=game+booster+no+lagPDF 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_off0000e75c.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xE75C 18260 bytes
SHA-256: 3c8f9c1b3a272e7073d986fbbae4d06d78fa890ee36fe9f968f7b9cf658f72f9
font_01_sfnt_off0001166d.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x1166D 10540 bytes
SHA-256: 1e9fc0b8f3d0f39261a8a452fb370e67c309845538407a9726f839f6e8ed04e6
font_02_sfnt_off00012e7b.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x12E7B 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1