Malicious PDF — malware analysis report

Static analysis result for SHA-256 a83d7569fcfc335c…

MALICIOUS

PDF

73.0 KB Created: 2021-09-01 12:53:05 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-10-07
MD5: faa52cb8e6daf170e56f147338a1470d SHA-1: 5deb879ab40024d403880434b1d6d1103a211f77 SHA-256: a83d7569fcfc335ce85a5ff3d880d0a8e59e3bb4b57aca2f3ccf056a7f04126e
156 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment T1203 Exploitation for Client Execution

This PDF file was flagged by multiple heuristics and a machine learning classifier as malicious, with ClamAV identifying it as a phishing trojan. The document functions as a link farm, containing numerous URLs pointing to compromised WordPress installations and other disposable hosting. These links likely serve to redirect users to phishing sites or download further malicious payloads.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9915

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 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://milcontabil.com.br/wp-content/plugins/super-forms/uploads/php/files/ohf1mu0a3pr4nl79jlbmq1shd6/53498272964.pdf In PDF document text
    • https://mvservice.it/file/54756433749.pdfIn PDF document text
    • https://www.kbstephens.com/wp-content/plugins/super-forms/uploads/php/files/9eac76b8eec3d489ed581ce95e033254/86917170285.pdfIn PDF document text
    • https://immobiliaresancarlotrieste.it/file/pidifepivorijeke.pdfIn PDF document text
    • https://alshamiltrading.com/alshamilfiles/file/12317546488.pdfIn PDF document text
    • http://honghuibio.com/d/files/torisapekizedeviraterowik.pdfIn PDF document text
    • https://highrise.pl/file/99253561683.pdfIn PDF document text
    • https://engravestone.com/wp-content/plugins/formcraft/file-upload/server/content/files/1608a80746ae31---89472685322.pdfIn PDF document text
    • http://le-lemniscus-incandescent.fr/ckeditor/upload/files/601281040.pdfIn PDF document text
    • https://jiptv.nl/wp-content/plugins/super-forms/uploads/php/files/8g0hld6hf695odkejilh2mp6no/taninazaxikunalivodegikul.pdfIn PDF document text
    • http://mebelhotel.ru/images/news/file/8616340416.pdfIn PDF document text
    • http://windcampus.com/wp-content/plugins/formcraft/file-upload/server/content/files/1606ea1c1a9a2f---kukivurexoparaz.pdfIn PDF document text
    • http://megaeventoa100.com/clients/f/fa/fa03970f5feff24be7017758158681b9/File/xegexobejobujaxegesos.pdfIn PDF document text
    • http://agataklimowska.pl/userfiles/file/gufuta.pdfIn PDF document text
    • https://valleyrestoration.net/home/apf/public_html/ckfinder/userfiles/files/36809424766.pdfIn PDF document text
    • https://doctmcooper.com/userfiles/files/43408278358.pdfIn PDF document text
    • http://willtorock.com/wp-content/plugins/formcraft/file-upload/server/content/files/160904afe3864e---fadififugekidaxeri.pdfIn PDF document text
    • https://alusol-kw.com/ckfinder/userfiles/files/81567151018.pdfIn PDF document text
    • http://asea-admin.com/_userfiles/file/20210731071020.pdfIn PDF document text
    • http://irmascaritasdejesus.org.br/wp-content/plugins/formcraft/file-upload/server/content/files/1611b3a9ac4144---57535120683.pdfIn PDF document text
    • https://gaseg.com/wp-content/plugins/super-forms/uploads/php/files/imfi0fp19tm908pjmbvo5kl4ud/gunose.pdfIn PDF document text
    • https://drahmetbostanci.com/wp-content/plugins/formcraft/file-upload/server/content/files/1607674425054f---xojapuxobiloxurivevejut.pdfIn PDF document text
    • http://bestforfishing.com/wp-content/plugins/super-forms/uploads/php/files/0d94e162d7e98a258498e0df270ee6fa/79489269445.pdfIn PDF document text
    • https://www.yoursurveysurveyors.co.uk/wp-content/plugins/formcraft/file-upload/server/content/files/161117b6a815d7---sizakegilaxugujomewew.pdfIn PDF document text
    • http://btfa.tw/upload/files/jokubajen.pdfIn PDF document text
    • http://benetalent.com/upload/files/papomesu.pdfIn PDF document text
    • https://feedproxy.google.com/~r/Uplcv/~3/DOqCt-cVA4I/uplcv?utm_term=lalitha+audios+dj+songs+download+2020+mp3PDF 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_off0000bb7c.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xBB7C 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
font_01_sfnt_off0000d38e.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xD38E 15696 bytes
SHA-256: 45ed8416b3fdd888b796074d14ae9c192a977e4d82d3faab44674cb9410f4882
font_02_sfnt_off0000fbc9.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xFBC9 11292 bytes
SHA-256: ff3ac2d7cb4689acf4081c26a30e175aebe054ad5d71e358b535530d644e9ce2