Malicious PDF — malware analysis report

Static analysis result for SHA-256 ab3dc8d15c5683af…

MALICIOUS

PDF

93.7 KB Created: 2021-06-26 00:57:44 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3)
MD5: 831e63ccada85f0aaf64af6449dbaa19 SHA-1: 4e2be0554dd69e2b7687e95b30c0626a5e1e913c SHA-256: ab3dc8d15c5683af0ac6759116705678a6c57f822981678423f51db1c20b0d9e
156 Risk Score

Malware Insights

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

The PDF contains a large number of external links, many pointing to compromised WordPress sites or disposable hosting, indicating a link farm designed to distribute malicious content or phish users. The ML classifier and ClamAV detection strongly suggest malicious intent, likely related to phishing or malware delivery.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9927

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 https://wastran.ru/uplcv?utm_term=hsk+4+standard+course+workbook+answers+pdf
    • https://amitadevnani.com/userfiles/file/wepaguponigewobalito.pdf
    • http://www.birapart.com/wp-content/plugins/formcraft/file-upload/server/content/files/16089fa84b4298---33224148588.pdf
    • http://akgikorea.com/file_upload/fck_upfile/file/poteputavemokugobubex.pdf
    • http://dmn.ca/wp-content/plugins/formcraft/file-upload/server/content/files/160a7895d2b1c3---84458030658.pdf
    • https://extremetour74.ru/wp-content/plugins/super-forms/uploads/php/files/245da5f28d5281a98f6c89c7f9222173/96639734159.pdf
    • https://alatheir.com/atheirwsfiles/file/sizorar.pdf
    • http://www.argentum.com/wp-content/plugins/super-forms/uploads/php/files/gd58qcn4lqh7bsorss8pfd3khp/xiluburuzo.pdf
    • https://sckstone.com/wp-content/plugins/super-forms/uploads/php/files/59b52efa61f01ec0687f6341f96054e4/wezopemol.pdf
    • http://akbmodel.com/wp-content/plugins/formcraft/file-upload/server/content/files/160c9404a953f4---letojunex.pdf
    • http://portalcom-b2b.es/img/user///file/_0470626001620586912.pdf
    • http://atthaya.com/file_media/file_image/file/soloxa.pdf
    • https://oiweld.com/wp-content/plugins/super-forms/uploads/php/files/f448c4cc4838cef5c9f135ab73daf407/bomubatuvip.pdf
    • https://bilbox.es/wp-content/plugins/super-forms/uploads/php/files/84cf188fcb488727480bf9265164abb6/raparutikeleloxivixe.pdf
    • http://drairtools.com/ckfinder/userfiles/files/82555478643.pdf
    • https://oncetrabzon.com/resimler/files/bavelojefomes.pdf
    • https://plentis.eu/ckfinder/userfiles/files/lewiwedaguxevuzaderaka.pdf
    • https://bostoncake888.com/UserFiles/files/tizapuponuzokezegezox.pdf
    • https://www.litesourcenc.com/wp-content/plugins/super-forms/uploads/php/files/d619fb95694db9f4bebd3a0828329d2e/27088132382.pdf
    • https://shen-su.eu/gfx/userfiles/files/gewizoteberakimis.pdf
    • http://www.zopfitravel.com/wp-content/plugins/formcraft/file-upload/server/content/files/1607dba11e4098---90285651337.pdf
    • http://aeskulap24h.com/wp-content/plugins/formcraft/file-upload/server/content/files/160b306c029b15---zejeralobepuvamimetinetuz.pdf
    • http://cpgny.com/userfiles/files/1169595561.pdf
    • http://www.1000ena.com/wp-content/plugins/formcraft/file-upload/server/content/files/1609836a44cca0---samosetukekuwusaro.pdf
    • http://www.w3.org/1999/02/22-rdf-syntax-ns#
    • http://purl.org/dc/elements/1.1/
    • http://ns.adobe.com/pdf/1.3/
    • http://ns.adobe.com/xap/1.0/
    • http://ns.adobe.com/xap/1.0/mm/
    • http://ns.adobe.com/xap/1.0/rights/
    • http://dejavu.sourceforge.net
    • http://dejavu.sourceforge.net/wiki/index.php/License

Extracted artifacts 4

Files carved from inside the sample during analysis.

FilenameKindSourceSize
font_00_sfnt_off00010107.bin
7c447cd0c4b3cd839c56dc38d446d0efca45c1143b84e352562e41f9bfa28d6b
pdf-font-stream PDF embedded font (sfnt) at offset 0x10107 10960 bytes
font_01_sfnt_off00011a72.bin
1ccb9243e3be76179a9593c4bcf8fcdbb29c0a93e9d7165459f81708b83163a5
pdf-font-stream PDF embedded font (sfnt) at offset 0x11A72 16652 bytes
font_02_sfnt_off000145a0.bin
9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
pdf-font-stream PDF embedded font (sfnt) at offset 0x145A0 16792 bytes
font_03_sfnt_off00015dad.bin
58c6ba57afdfad36af3a63436475a691b4ccfe3b787e0ad8160883184ef97754
pdf-font-stream PDF embedded font (sfnt) at offset 0x15DAD 2616 bytes