Malicious PDF — malware analysis report

Static analysis result for SHA-256 1b28c7dfc925eb29…

MALICIOUS

PDF

83.1 KB Created: 2021-10-10 12:53:33 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-11-25
MD5: e8c7e391fd634451f1c8e40cec920936 SHA-1: ba9a3b4b796563a75289faab6b65d2b4dbe1af83 SHA-256: 1b28c7dfc925eb29cd2c2f2f45ac3e4f53bd5d706cd02e6e9c282b663785f89e
156 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment

The PDF contains numerous links to external websites, many hosted on compromised or disposable domains, indicating a link farm designed to redirect users. The ML classifier and ClamAV detection strongly suggest malicious intent, likely phishing or malware delivery. Although no scripts were explicitly extracted, the PDF structure and embedded URLs are indicative of a malicious document, potentially leveraging embedded JavaScript for redirection or further exploitation.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9985

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 https://www.lokalesichtbarkeit.de/wp-content/plugins/super-forms/uploads/php/files/ovsal9s7jjsdgmevqi5rvsllhc/siniji.pdf In PDF document text
    • http://bjqyms.com/filespath/files/20210926142516.pdfIn PDF document text
    • http://synfarm.com/upload/files/71020408161.pdfIn PDF document text
    • http://varosom.hu/userfiles/files/vamunixofu.pdfIn PDF document text
    • http://es-umzuege-transporte.de/wp-content/plugins/super-forms/uploads/php/files/be483a952b0e624368681de843254fae/tawuvukitapazumawe.pdfIn PDF document text
    • https://ienter.bg/files/20951667251.pdfIn PDF document text
    • https://phukienbep.net/media/files/12661843441.pdfIn PDF document text
    • http://abwcoliseum.com/uploads/files/fafatawade.pdfIn PDF document text
    • http://jfhconsultancy.nl/userfiles/files/sunipirora.pdfIn PDF document text
    • http://twilaw.com/files/files/vewedugu.pdfIn PDF document text
    • http://vibrosystem.ro/wp-content/plugins/formcraft/file-upload/server/content/files/1612fe68a70e81---sagasazewud.pdfIn PDF document text
    • http://gabinetpro.gabinetpro.pl/kosmetyczka/krakow/files/18003006237.pdfIn PDF document text
    • http://es-iyashinomori.net/yamituki-n/uploads/files/8098429310.pdfIn PDF document text
    • http://jimsclub.net/new/board/img_tinfo/file/20210919005216.pdfIn PDF document text
    • http://birizgardenhotel.com/userfiles/file/94068094887.pdfIn PDF document text
    • https://playgametoday.ru/wp-content/plugins/super-forms/uploads/php/files/e0196051cd54c0e3fbeda0c73e450167/63383612781.pdfIn PDF document text
    • http://ysenb.kr/board/file/editor/file/remewatibadejovemusafuxi.pdfIn PDF document text
    • https://tonerihned.cz/userfiles/file/mokelibozokapolurofudit.pdfIn PDF document text
    • https://hensuyenpqa.traigiongthuha.com/ckfinder/userfiles/files/pajemowip.pdfIn PDF document text
    • https://skl.deindrukdemo.nl/upload/files/79851450408.pdfIn PDF document text
    • https://gentrilieu.vn/userfiles/file/51428130914.pdfIn PDF document text
    • https://feedproxy.google.com/~r/1eyvgo/aqOO/~3/BkSY9tpko7c/uplcv?utm_term=another+word+for+art+galleryPDF 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_off0000e15b.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xE15B 10556 bytes
SHA-256: 1e1dfb4ac442b1d52a9ae906daa394a9056feb6e41798c74f777c3b60be35362
font_01_sfnt_off0000f945.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xF945 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
font_02_sfnt_off00011157.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x11157 17700 bytes
SHA-256: 95e81fd7a1b6695b26402bb0b56f862d5623dddfd82fdea17cbd1eb8bc7f93cc