Malicious PDF — malware analysis report

Static analysis result for SHA-256 f5a5d1118b3589ac…

MALICIOUS

PDF

78.2 KB Created: 2021-09-08 23:42:46 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-10-05
MD5: d7514eef8d21fb3a942da4ad94c80125 SHA-1: 1415e35a344f2f1796a80baaa1cd9f53f947baeb SHA-256: f5a5d1118b3589acfddd520be63313a708a17bf651501ab33d4b3be857d5b8fe
166 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment

The PDF contains numerous links to external websites, with several heuristics indicating a link farm on disposable hosting and random URLs. 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 numerous external links point towards a spearphishing attachment attack vector.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9980

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 to algorithmically-generated URL high PDF_RANDOM_URL_LINK
    PDF contains a clickable HTTP(S) link whose host looks algorithmically generated (pronounceable-random labels) and whose path/query carries a long high-entropy token. This is the randomized-redirector pattern of malspam phishing lures — the visible document is only a prompt — not a PDF parser vulnerability.
  • 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 https://griby.biz/ckfinder/userfiles/files/wobefiwerobupewalunawi.pdf In PDF document text
    • http://www.ashtralmedia.com/wp-content/plugins/formcraft/file-upload/server/content/files/161304f174bc7e---70567895631.pdfIn PDF document text
    • https://office-agglo-larochelle.fr/userfiles/file/53586709030.pdfIn PDF document text
    • http://premiumcsp.com/uploads/files/13537839696.pdfIn PDF document text
    • http://ankamet.com/userfiles/file/14527300817.pdfIn PDF document text
    • http://bogaarchitetti.it/userfiles/files/mabow.pdfIn PDF document text
    • http://willbramephotography.com/zubavudunipo.pdfIn PDF document text
    • http://prttour.ca/FileData/ckfinder/files/20210905_63C75D372750E74E.pdfIn PDF document text
    • https://akrmedia.no/ckfinder/userfiles/files/nokomizakel.pdfIn PDF document text
    • http://businessnavigator.in/ckeditor/uploads/files/lurubiwud.pdfIn PDF document text
    • http://sangjeom.com/userfiles/file///lujoneza.pdfIn PDF document text
    • http://lucidareemantenerepavimentifaidate.it/userfiles/files/63774477621.pdfIn PDF document text
    • http://wami.cc/data/files/96607400794.pdfIn PDF document text
    • http://baikalspring.ru/ckfinder/userfiles/files/zimevekovebiruno.pdfIn PDF document text
    • http://cameralehiep.com/hinhanh_fckeditor/file/38333995162.pdfIn PDF document text
    • http://wyadonline.com/userfiles/file/sejerivixilekosemofefene.pdfIn PDF document text
    • http://szyqjsj.com/UploadFile/file/20210907155056883.pdfIn PDF document text
    • http://ulsantour.com/FileData/ckfinder/files/20210909_CD7AC0FB975E2BE8.pdfIn PDF document text
    • http://skupka23.ru/upload/m/fejatiloremav.pdfIn PDF document text
    • https://learn-atdi.com/uploads/files/rowakebemomobepalafelig.pdfIn PDF document text
    • https://zerling.eu/nico/images/files/86886667973.pdfIn PDF document text
    • http://giaydantuongphongngudep.com/images/news/file/rogudiniki.pdfIn PDF document text
    • http://www.vnv.nu/admin/library/ckfinder/userfiles/files/42063427488.pdfIn PDF document text
    • http://gingerwooddesign.com/wp-content/plugins/formcraft/file-upload/server/content/files/161304fff86a2a---65038265425.pdfIn PDF document text
    • http://espokebar.com/uploads/files/lomalu.pdfIn PDF document text
    • https://feedproxy.google.com/~r/Uplcv/~3/PmAiG5ZyT-k/uplcv?utm_term=1337+x+ioPDF 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_off0000d096.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xD096 9572 bytes
SHA-256: 8c9fba68fcd21696be0d80a359d841765dc517bbeffc3cb7b372d1a0b1dc48ec
font_01_sfnt_off0000e55d.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xE55D 17768 bytes
SHA-256: 69a8ccee3df3155a8ac00632b9a4f17137ed2be4b8fa202339e7dc95a0441b37
font_02_sfnt_off0001139c.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x1139C 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1