Malicious PDF — malware analysis report

Static analysis result for SHA-256 5f7efa9ab3ab4eca…

MALICIOUS

PDF

77.0 KB Created: 2021-09-18 18:28:56 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-10-23
MD5: db2275615a7ba75a19c019b7817bd0f5 SHA-1: 5ce90ffbf4073728b30c3a40e6f64b278c7dd26b SHA-256: 5f7efa9ab3ab4eca321a765f62d333a21e954d7ade7f2c90981f8fd0f06a4774
126 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment

The PDF file was flagged by multiple heuristics, including a critical ClamAV detection and an ML classifier, indicating malicious intent. The presence of numerous external URIs and the 'PDF_SEO_DISPOSABLE_LINK_FARM' heuristic suggest the document is designed to redirect users to potentially harmful websites. While no scripts were explicitly extracted, the PDF format can embed JavaScript, and the overall structure points towards a phishing or malware distribution lure.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9943

Heuristics 5

  • ClamAV: Pdf.Phishing.Trojan-d2528dad23a95d95-d2528dad23a95d95-10044376-0 critical CLAMAV_DETECTION
    ClamAV detected this file as malware: Pdf.Phishing.Trojan-d2528dad23a95d95-d2528dad23a95d95-10044376-0
  • 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 https://pistant.ru/uplcv?utm_term=null+clash+of+clans+apk PDF link annotation
    • https://jyapa.com/jhuoyue/uploadfiles/36674845041.pdfIn PDF document text
    • https://unicon-msk.ru/data/files/fimaxorewafug.pdfIn PDF document text
    • http://varadimasszazs.hu/uploads/files/45693174958.pdfIn PDF document text
    • http://dgxzz.com/uploadfile/file/dorex.pdfIn PDF document text
    • http://studioaeditecne.it/userfiles/file/98247986003.pdfIn PDF document text
    • https://drisraadentalcenter.com/userfiles/file/jazujenuwuxoriwaloxi.pdfIn PDF document text
    • http://fsanaq.com/upload/file/21091615123800475834bed0mbb9nb.pdfIn PDF document text
    • http://ajtoablakcentrum.com/_user/file/dunoxefuduton.pdfIn PDF document text
    • https://machnhaduong.com/images/uploads/files/kivedoruwugesofelogana.pdfIn PDF document text
    • http://shipsupply.ru/userfiles/files/motidodezitogorafa.pdfIn PDF document text
    • http://www.neoneophytou.com/ckfinder/userfiles/files/tabodobidixixek.pdfIn PDF document text
    • http://www.davidwoodpersonnel.com/wp-content/plugins/formcraft/file-upload/server/content/files/16130b56f3a617---61060433792.pdfIn PDF document text
    • http://jtravel.clickis.kr/FileData/ckfinder/files/20210906_536010CAD699069F.pdfIn PDF document text
    • http://win-sonic.com/ck_imgs/files/widorajuwup.pdfIn PDF document text
    • http://psychanalyste-gard.fr/ckfinder/userfiles/files/12588740441.pdfIn PDF document text
    • https://www.eos.org.eg/ckfinder/userfiles/files/vadilotiwegikezoxada.pdfIn PDF document text
    • http://veiligheidsslot.nl/ckfinder/userfiles/files/sisumewizeg.pdfIn PDF document text
    • http://cana.vn/uploads/userfiles/file/69342344029.pdfIn PDF document text
    • https://majorsagilekvaros.hu/uploads/file/28152941311.pdfIn PDF document text
    • https://radiosmile.hu/upload/file/51435251443.pdfIn PDF document text
    • http://toanthinh.vn/webroot/img/files/lajobozubezitozu.pdfIn PDF document text
    • http://www.1atlanticfunding.com/wp-content/plugins/formcraft/file-upload/server/content/files/1612f731d490db---11892608281.pdfIn PDF document text
    • http://rockhouseschool.com/rockhouse/uploads/files/donojubavi.pdfIn PDF document text
    • http://stlnsk.ru/uploads/file/kasarovafevuxajuxu.pdfIn PDF document text
    • http://ping-property.com/user_img/files/novodumivanebosapifaz.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_off0000c814.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xC814 10324 bytes
SHA-256: 5e42059b297ccec48dbe90ce803c24a3a12ae99e3736201607559a9ad7e096fc
font_01_sfnt_off0000df53.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xDF53 18036 bytes
SHA-256: 393559c0f2a5238640b8b5ddc4e2d8422b2eb114841c7f236bc465437b2c8cc7
font_02_sfnt_off00010e82.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x10E82 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1