Malicious PDF — malware analysis report

Static analysis result for SHA-256 16a3c97f7e7000c1…

MALICIOUS

PDF

198.8 KB Created: 2021-08-02 02:13:34 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3)
MD5: 4d1ed1e6adad947286d00b430efd9a6e SHA-1: 6d420e020c2dc64e24d218c11572c05c111264de SHA-256: 16a3c97f7e7000c1731d610bdb741767c2952a96b08bb8e4c2e4d3dd09bfd302
166 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment

The PDF contains multiple links to external resources, with several pointing to compromised WordPress upload directories. The ML classifier and ClamAV detection strongly indicate malicious intent, likely to deliver a secondary payload. The presence of PDF_RANDOM_URL_LINK and PDF_COMPROMISED_CMS_UPLOAD_LINK_FARM heuristics suggests a pattern of distributing malware through compromised web infrastructure.

Machine Learning

  • Nyx PDF Classifier malicious score 0.7662

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 to algorithmically-generated URL high PDF_RANDOM_URL_LINK
    PDF contains a clickable HTTP(S) link whose host looks algorithmically generated (pronounceable-random labels) and whose path/query carries a long high-entropy token. This is the randomized-redirector pattern of malspam phishing lures — the visible document is only a prompt — not a PDF parser vulnerability.
  • 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.
  • 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://grupo-bahia-real-estate.com/ckfinder/userfiles/files/lamevupekasa.pdf
    • https://www.kunapak.com/wp-content/plugins/super-forms/uploads/php/files/d35iu5nmqgkopi7344c5lcp1fh/20454584650.pdf
    • https://kalatranslation.co.uk/wp-content/plugins/super-forms/uploads/php/files/8l3djjqs3btpgr9gakod72o4be/26623451106.pdf
    • https://tahitotfaluovodak.hu/ckfinder/userfiles/files/61735988425.pdf
    • http://www.aqsclimited.com/EditorImages/file/58069654400.pdf
    • http://trips-in.com/ckupload/files/42991583303.pdf
    • https://vkgnassociates.com/dayafter/uploadimages/newsimages/file/81211519638.pdf
    • https://gearforfree.com/wp-content/plugins/super-forms/uploads/php/files/gsp2bmpuog1o26qkrr2ks2el9k/bukojisipan.pdf
    • http://coyada.com/up_images/up_images/jivatorosazipime.pdf
    • https://socialacademy.gr/wp-content/plugins/super-forms/uploads/php/files/0470acf6e67049731304d595ceeac769/37107616600.pdf
    • http://quickfix-poland.com/wp-content/plugins/formcraft/file-upload/server/content/files/160a5a16bc8147---refiwirapapusuw.pdf
    • http://www.argentum.com/wp-content/plugins/super-forms/uploads/php/files/le5vrltpj9aa7goj3opg88d8ov/3042877555.pdf
    • https://watfordfairtrade.org/app/webroot/img/files/jijazekono.pdf
    • http://prplus4u.com/ckupload/files/xisatezomax.pdf
    • http://scottleddy.net/clients/862555/File/fupinibadekifibe.pdf
    • https://bnbcostaverde.it/userfiles/file/xumat.pdf
    • http://grandbarnettfamily.com/clients/a/a0/a01b80d98e57c38af56892ab55e7d82f/File/mepen.pdf
    • https://xn--22ck6bdp5cach0mc23a.com/ckfinder/userfiles/files/fadamidikugemijozabu.pdf
    • https://izharfoster.com/wp-content/plugins/formcraft/file-upload/server/content/files/160bc95feb2934---ginuvovi.pdf
    • https://www.alphaveneers.com/wp-content/plugins/super-forms/uploads/php/files/f6ec7d908e3f5b857692a636c6807103/84774230109.pdf
    • http://busankid.com/webfiles/board/file///42799008481.pdf
    • https://bonekarusa.com/contents//files/gugutapevavumumufef.pdf
    • http://maduraigarlandshop.com/userfiles/file/23134025947.pdf
    • http://hilimall.ae/uploads/files/19572407104.pdf
    • https://ambulatorioveterinariosismondi.eu/file/80368225396.pdf
    • https://www.enviedecrire.com/wp-content/plugins/formcraft/file-upload/server/content/files/160d89dc2eba4d---69889248799.pdf
    • https://feedproxy.google.com/~r/1eyvgo/aqOO/~3/GLLx1DTH0VQ/uplcv?utm_term=pastoral+symphony+andre+gide+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_off0002aa79.bin
9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
pdf-font-stream PDF embedded font (sfnt) at offset 0x2AA79 16792 bytes
font_01_sfnt_off0002c290.bin
cb149fe1667c661c43044beda4d361b427341a8d19fc9786eb0fdb305f09c5c4
pdf-font-stream PDF embedded font (sfnt) at offset 0x2C290 11060 bytes
font_02_sfnt_off0002dbf4.bin
a206fa0f6eae3aa6b4698fbab7ce78fcb2a4b308ef8ace84cfa36b4afff62972
pdf-font-stream PDF embedded font (sfnt) at offset 0x2DBF4 17796 bytes