Malicious PDF — malware analysis report

Static analysis result for SHA-256 263ee71341c4c9e9…

MALICIOUS

PDF

74.3 KB Created: 2021-09-10 19:07:58 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-10-27
MD5: 76a8ba6fb15e7b71d0f1bb5797173756 SHA-1: 7dfc044dad31390e66933b3af3cbc3ac6a6f07cd SHA-256: 263ee71341c4c9e995cbe2c7fc11c075f964ab0c60ebd08d0effb9f7580ebe88
126 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment

The file was detected as malicious by ML classifiers and ClamAV, indicating a high likelihood of malicious intent. It contains numerous embedded URLs, many of which point to PDF files on various domains, suggesting a link farm or redirection mechanism. The PDF_SEO_DISPOSABLE_LINK_FARM heuristic further supports this, indicating a strategy to obscure the final destination. While no scripts were explicitly extracted, the nature of the embedded URLs and the overall detection suggests it's designed to lead users to potentially harmful content.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9840

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://azbuka-d.ru/ckfinder/userfiles/files/bifunofogefitewuvixewez.pdf In PDF document text
    • https://rumputhijau.com/contents/files/kamejaxotutepakexivebu.pdfIn PDF document text
    • http://fixafilm.se/userfiles/file/45804465821.pdfIn PDF document text
    • https://birutelorasin.com/contents/files/65058454356.pdfIn PDF document text
    • http://zhizhencn.com/filespath/files/20210910102739.pdfIn PDF document text
    • https://osikovo.eu/webroot/img/content/files/pagonekuxudukukodo.pdfIn PDF document text
    • http://votejoedestefano.com/editorData/file/kipivorejakiv.pdfIn PDF document text
    • http://villaturri.it/wp-content/plugins/formcraft/file-upload/server/content/files/1613a7757dd2f3---dexolivolutu.pdfIn PDF document text
    • http://cnpair.com/userfiles/file/66289544569.pdfIn PDF document text
    • https://linhquan-group.com/upload/ck/files/31218437709.pdfIn PDF document text
    • https://alfa-clining.ru/wp-content/plugins/super-forms/uploads/php/files/a654607c30c24bb17f7f537f98946f21/72115251844.pdfIn PDF document text
    • https://albertoangel.sinecsas.com/ckfinder/userfiles/files/56824709649.pdfIn PDF document text
    • https://nacituran.com/userfiles/file/ruxemilupuni.pdfIn PDF document text
    • https://alohasafaris.com/files/mizaromufuzaxigugonijusu.pdfIn PDF document text
    • http://xn----ftbkdcamitb5h.xn--p1acf/files/fck/file/kuvisovetamiwixoluwa.pdfIn PDF document text
    • http://actlogistic.vn/upload/editor/files/mavonovexukawopafu.pdfIn PDF document text
    • http://ferrocom-spb.ru/userfiles/files/mebafojimaxuruwerir.pdfIn PDF document text
    • http://boathousebrokerage.com/userfiles/file/48718173107.pdfIn PDF document text
    • http://ijdssymposium.eu/upload/lazewomazotokas.pdfIn PDF document text
    • https://108pizza.pl/uploads/userfiles/files/bupikuzalukisamanavadana.pdfIn PDF document text
    • https://psg66.ru/admin/ckfinder/userfiles/files/3656699115.pdfIn PDF document text
    • http://kortennis.co.kr/B/ck/ckfinder/userfiles/files/26935915483.pdfIn PDF document text
    • http://balmybnb.com/t/tutorfirm/uploads/ck/files/27168251478.pdfIn PDF document text
    • https://horacebatten.com/ckfinder/userfiles/files/bisikajujubuzubiwivoxe.pdfIn PDF document text
    • http://hanhthien.net/uploads/file/72197641297.pdfIn PDF document text
    • http://studiosantomauro.it/userfiles/files/tosokijokevisitegenim.pdfIn PDF document text
    • https://feedproxy.google.com/~r/1eyvgo/aqOO/~3/GLLx1DTH0VQ/uplcv?utm_term=my+talking+angela+unlimited+allPDF 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_off0000bfb7.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xBFB7 16980 bytes
SHA-256: 72736729137aaac0de41e142abc454b1ab18185012f6afa31f97a39deef78faa
font_01_sfnt_off0000ec01.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xEC01 10500 bytes
SHA-256: 64fb7edd1aa9dccabbf89a07925c5ef6f030aacdf73cd92688bd9a87b0d5d7b4
font_02_sfnt_off0001039a.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x1039A 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1