Malicious PDF — malware analysis report

Static analysis result for SHA-256 257e8131b6cc925a…

MALICIOUS

PDF

82.5 KB Created: 2021-09-06 20:49:08 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3)
MD5: e920f4afda7203677aafbdb2f2535641 SHA-1: eb6b762ac5f64b4025df9f394e4244216f121d25 SHA-256: 257e8131b6cc925a31ec27c955a61d67a4e077e3ac52615fdb9bc02a8e29d75e
156 Risk Score

Malware Insights

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

The PDF contains numerous links, many pointing to websites hosted on compromised WordPress installations, indicating a link farm designed to redirect users. The ML classifier and ClamAV detection strongly suggest malicious intent, likely for phishing or distributing further malware. No scripts were extracted, but the heuristic findings point to a malicious link distribution pattern.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9960

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://artsketch.ru/wp-content/plugins/super-forms/uploads/php/files/18a3302833ac9533206936b3561d4e6f/xofubefadaxawofuzudunoj.pdf
    • https://kes-stv.ru/wp-content/plugins/super-forms/uploads/php/files/cfacbb3a1e796d7e7af3f7f3abe3ab19/37167978199.pdf
    • http://yamamatoen-wanwan.jp/ckfinder/userfiles/files/4607263.pdf
    • http://le-lemniscus-incandescent.fr/ckeditor/upload/files/64207451819.pdf
    • http://socialbomjesus.org.br/wp-content/plugins/formcraft/file-upload/server/content/files/160c0a509c9ff7---16954760847.pdf
    • http://xn----8sbfeahwarn6ac1adp3fb2p.xn--p1ai/userfiles/file/10295244376.pdf
    • http://perfekttorun.pl/pliki/36139680720.pdf
    • https://www.ergunaygoren.com/wp-content/plugins/formcraft/file-upload/server/content/files/1607a7db84fe3b---89095378108.pdf
    • https://www.properties-thassos.com/wp-content/plugins/super-forms/uploads/php/files/q93lfc8lb87ai2n2ip9hg5s8pa/guvoxawikuvul.pdf
    • https://alquimia.in/admin/fckeditor/editorfile/fafokenom.pdf
    • http://2sisaccount.com/userfiles/files/30277812993.pdf
    • https://ocvirapuato.com.mx/wp-content/plugins/super-forms/uploads/php/files/7efa60587a610a79375c216a7b079aa2/6977311073.pdf
    • https://hkfew.org.hk/ckfinder/userfiles/files/2849019123.pdf
    • https://esteticarcare.com/wp-content/plugins/super-forms/uploads/php/files/af812b784d8c7f590283d6f82aead03c/vusojelen.pdf
    • https://westcoastmovers.ca/wp-content/plugins/super-forms/uploads/php/files/4j1l5rbk5c79aicro6s5d923d0/76587851415.pdf
    • https://unique.global/wp-content/plugins/super-forms/uploads/php/files/d0214d6e24070af74275080d76b72e73/mutekajotugekona.pdf
    • http://e-hematologica.com/users//file/13677135947.pdf
    • https://alianzatours.com/imagenes/file/xawesuliteluzotebup.pdf
    • http://amoy-art.com/Upload/file/pagedadu.pdf
    • https://cullinanconstruction.com/wp-content/plugins/super-forms/uploads/php/files/p9bapovtdimprbc5gd4r8hi9s1/kisipilijilipataz.pdf
    • http://www.iycadana.org/wp-content/plugins/super-forms/uploads/php/files/o1umuk00hr8f6bdubsfr04fbk4/tulumizike.pdf
    • https://fond.ru/userfiles/file/92357893716.pdf
    • http://gleneaglehoa.org/images/file/botovagetizepobu.pdf
    • https://feedproxy.google.com/~r/1eyvgo/aqOO/~3/ngfLrbzwjls/uplcv?utm_term=mission+d%27audit+externe+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 3

Files carved from inside the sample during analysis.

FilenameKindSourceSize
font_00_sfnt_off0000dcd1.bin
757c109b3a2cabb33256204ce52cf14e997bbafebbf67b5db8b8db467bd9c3cf
pdf-font-stream PDF embedded font (sfnt) at offset 0xDCD1 18668 bytes
font_01_sfnt_off00010a76.bin
d5aabf35fc567edef39d3ea833947b3ebd68de6a7d95ac25a6beff505935f6b5
pdf-font-stream PDF embedded font (sfnt) at offset 0x10A76 10672 bytes
font_02_sfnt_off00012325.bin
9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
pdf-font-stream PDF embedded font (sfnt) at offset 0x12325 16792 bytes