Malicious PDF — malware analysis report

Static analysis result for SHA-256 d533cbd4e1a339d7…

MALICIOUS

PDF

85.6 KB Created: 2021-09-17 11:18:49 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-10-14
MD5: 054c9c3863ad9b2b9747dfa8b5b5b87f SHA-1: 9d14d5ae7359ab343718203d4353f464046f0ee0 SHA-256: d533cbd4e1a339d7b2621c37d15571052b07195e9bdf15d8cbf53eb54dd3d8bd
156 Risk Score

Malware Insights

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

The PDF was flagged by ClamAV as Pdf.Phishing.Trojan and a machine learning classifier indicated a high probability of maliciousness. Analysis revealed it functions as a link farm, with numerous embedded URLs pointing to various websites. Several of these URLs lead to compromised CMS uploads or disposable hosting, suggesting an intent to distribute phishing content or malware.

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://wjvanderheidedienstverlening.nl/uploads/file/27583338604.pdf In PDF document text
    • http://fitnessklub-impuls.pl/uploads/assets/file/jiwifejulopovuka.pdfIn PDF document text
    • http://amako-ra.com/wp-content/plugins/super-forms/uploads/php/files/208d1645682a8e9311d2e86fe9dc15db/tajemugoxiped.pdfIn PDF document text
    • http://grabnerestriche.at/riraribiwogekep.pdfIn PDF document text
    • http://woodbridgeabw.com/uploads/files/xajokosiluxejoxez.pdfIn PDF document text
    • http://timebymtm.com/upload/files/sodaradabagedisitewege.pdfIn PDF document text
    • https://leosservices.com/userfiles/file/9195767382.pdfIn PDF document text
    • http://woonhuislift.info/wp-content/plugins/formcraft/file-upload/server/content/files/1613b128111251---69572282837.pdfIn PDF document text
    • http://h-st.nl/bestanden/files/35482062678.pdfIn PDF document text
    • http://saikunghouse.hk/userfiles/larumofoma.pdfIn PDF document text
    • https://vickers-electronics.co.uk/wp-content/plugins/super-forms/uploads/php/files/c4884e76ab548da1017503e77d7eb989/kilezadale.pdfIn PDF document text
    • http://isotope3.pm-ural.com/uploads/files/10809501472.pdfIn PDF document text
    • https://shrmivirtual.org/wp-content/plugins/super-forms/uploads/php/files/f4df012d0d9530019d2fe5404c41851a/65609792572.pdfIn PDF document text
    • http://tid.vn/upload/files/viraluzafuwomipuranubaxe.pdfIn PDF document text
    • https://casalindasbakery.com/ckfinder/userfiles/files/95837495804.pdfIn PDF document text
    • http://www.yt333.com/userfiles/20210913/file/1631526319.pdfIn PDF document text
    • http://master-br.ru/img/file/67537402600.pdfIn PDF document text
    • http://matchedtubes.de/userfiles/file/fenigiwuwomejefese.pdfIn PDF document text
    • http://khonggianxua.samdigroup.vn/app/webroot/upload/files/nomedemasavodowamedaja.pdfIn PDF document text
    • http://rcp-ranstadt.us/files/taluzo.pdfIn PDF document text
    • http://tongrentangthai.com/UserFiles/file/famozigiparotug.pdfIn PDF document text
    • http://gachmenminhchien.com/media/ftp/file/gopetazurefezo.pdfIn PDF document text
    • http://lingvastar.z-i-g-z-a-g.com/userfiles/files/72814862616.pdfIn PDF document text
    • http://sieuthibongda.net/ckfinder/userfiles/files/jamolotopo.pdfIn PDF document text
    • https://yarsan.ru/wp-content/plugins/super-forms/uploads/php/files/2efba29872e291c28926932abffd8711/nurejazovikevu.pdfIn PDF document text
    • https://feedproxy.google.com/~r/Uplcv/~3/1KS0DP0cxss/uplcv?utm_term=best+entertainment+games+for+androidPDF 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_off0000ea52.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xEA52 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
font_01_sfnt_off00010264.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x10264 17808 bytes
SHA-256: 6b042728cc952dfb7f15507fb56540985cb3fdac3d48a5ec95c20f781d4aa132
font_02_sfnt_off0001302b.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x1302B 10704 bytes
SHA-256: 07efbf966c60116f8006b38ef1f71f7a3ce178257161a1f8d2c1b97f678f991e