Malicious PDF — malware analysis report

Static analysis result for SHA-256 0137b3f80f82d3f5…

MALICIOUS

PDF

94.2 KB Created: 2021-07-20 19:19:56 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-11-25
MD5: d147acda5ce352e1a32a10cf8178a3c2 SHA-1: f42319cc000482794ab65f4523b180f7f759b138 SHA-256: 0137b3f80f82d3f590c58829233b5042dfd589dff921bb2d105f5dd1ead135fa
164 Risk Score

Malware Insights

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

The PDF contains numerous links, many pointing to compromised WordPress sites and disposable hosting, indicative of a link farm designed to redirect users. The ML classifier and ClamAV detection strongly suggest malicious intent, likely phishing or malware distribution through these links. No scripts were extracted, and the document body was unreadable, so the rationale is based on the URL analysis and heuristic firings.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9992

Heuristics 7

  • 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.
  • Visual download / call-to-action button lure low SE_DOWNLOAD_BUTTON
    Document contains a call-to-action phrase ('Click here to download', 'Download Now', etc.) — low-signal unless other findings point to a malicious workflow
  • 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://foundryindia.org/userfiles/file/81696704223.pdf In PDF document text
    • http://bioident.pl/photos_fck/file/xemuxavuwizivudewur.pdfIn PDF document text
    • https://www.lumisolar.pe/wp-content/plugins/formcraft/file-upload/server/content/files/16077f4c40b1d2---gobojofijututugugizugex.pdfIn PDF document text
    • https://copab.tn/216mag.svn/uploads/files/damajizifabosidugoxoxo.pdfIn PDF document text
    • http://hattingtoemrerogsnedker.dk/userfiles/file/fijuz.pdfIn PDF document text
    • http://wbbray.com/wp-content/plugins/formcraft/file-upload/server/content/files/16087b50b41691---wemagedusi.pdfIn PDF document text
    • https://mandalaconfeccao.com.br/wp-content/plugins/formcraft/file-upload/server/content/files/160b754059fa25---41541943540.pdfIn PDF document text
    • https://saraelv.no/wp-content/plugins/formcraft/file-upload/server/content/files/1608ace0eed35d---21367318249.pdfIn PDF document text
    • http://makesrealsense.com/ckfinder/userfiles/files/fesojagekepado.pdfIn PDF document text
    • https://vigiweb.cl/dinamicos/files/file/duvuxapamozoberusesi.pdfIn PDF document text
    • https://heritagelogs.com/wp-content/plugins/super-forms/uploads/php/files/v4rd1j9kcuhk66j4p6vfaj93q4/33216600032.pdfIn PDF document text
    • https://terlickodds.cz/www/www/fckphotos/file/dinemitoxemolabopi.pdfIn PDF document text
    • http://thietbiotovn.com/Images_upload/files/58465468529.pdfIn PDF document text
    • http://lichnyiybrand.ru/wp-content/plugins/formcraft/file-upload/server/content/files/160740127be961---89470367690.pdfIn PDF document text
    • https://feedproxy.google.com/~r/Uplcv/~3/BkSY9tpko7c/uplcv?utm_term=giancoli+physics+for+scientists+and+engineers+solutions+pdfPDF 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_off00010c47.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x10C47 17368 bytes
SHA-256: e57414a65ee4080db38afcfc91d6fb2c409d7352833ea31d1d1e51da0d8fc20a
font_01_sfnt_off000139e2.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x139E2 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
font_02_sfnt_off000151f9.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x151F9 11152 bytes
SHA-256: 5b7fd49e82abcc30a838349ea56b07e26b31bf5ee58e1455363e668354e2c810