Malicious PDF — malware analysis report

Static analysis result for SHA-256 df3f39dcce6f6a53…

MALICIOUS

PDF

69.8 KB Created: 2021-06-17 19:18:49 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 4.8.7) First seen: 2021-10-27
MD5: 3fa47ab06cbc71ef39dc396ad2aade3a SHA-1: 1a99937949064dab6a04801424a7b78e92297294 SHA-256: df3f39dcce6f6a53f9b48b59de40d5539200645f0062608f7dcb52e7310ce5bc
156 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment

This PDF file was detected as malicious by ClamAV and an ML classifier, indicating a phishing attempt. The document body, though heavily obfuscated, suggests a lure for a free PDF download. The numerous embedded URLs pointing to compromised WordPress sites and file upload directories further support the phishing and potential malware distribution vector.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9997

Heuristics 6

  • ClamAV: Pdf.Phishing.Trojan-d2528dad23a95d95-d2528dad23a95d95-10044376-0 critical CLAMAV_DETECTION
    ClamAV detected this file as malware: Pdf.Phishing.Trojan-d2528dad23a95d95-d2528dad23a95d95-10044376-0
  • 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://travelselection.us/wp-content/plugins/formcraft/file-upload/server/content/files/16086da157bd27---51529680076.pdf In PDF document text
    • http://qboardapp.com/wp-content/plugins/super-forms/uploads/php/files/b1aec41800fd4f0e49e6d47d853cc79b/12847598592.pdfIn PDF document text
    • http://kaplanpm.com/wp-content/plugins/formcraft/file-upload/server/content/files/160727a6772600---wezotabofig.pdfIn PDF document text
    • http://www.grupohk.com.br/wp-content/plugins/formcraft/file-upload/server/content/files/160827847794bd---vuxulesumumutelolibi.pdfIn PDF document text
    • https://mudrun.com/home/mud/public_html/ckfinder/userfiles/files/94633039374.pdfIn PDF document text
    • http://www.auditsi.com/wp-content/plugins/formcraft/file-upload/server/content/files/1606c796a73ae6---nizuto.pdfIn PDF document text
    • http://mateuszkucharski.pl/admin/file/26522626515.pdfIn PDF document text
    • https://pluckywize.com/wp-content/plugins/formcraft/file-upload/server/content/files/1606d65b2d7435---56309567237.pdfIn PDF document text
    • https://mikepromedia.com/wp-content/plugins/super-forms/uploads/php/files/04nucavjbros96p4l3fmf0dqm1/jupopedeveruk.pdfIn PDF document text
    • https://carlojans.com/cms/file/16554942727.pdfIn PDF document text
    • https://ascinfratech.com/clientprojects/trading/file/53354892355.pdfIn PDF document text
    • http://chiangmai-clean.com/user_img/files/wolokupajifu.pdfIn PDF document text
    • http://aaexpansionjoint.com/wp-content/plugins/formcraft/file-upload/server/content/files/160c9c97fe8f3a---jadapojotusoxobuxubileti.pdfIn PDF document text
    • https://www.hotel-palladium.gr/wp-content/plugins/super-forms/uploads/php/files/kodjodr4gn6uquh99l0okcl9gp/93289282327.pdfIn PDF document text
    • https://www.mercato.co.za/wp-content/plugins/formcraft/file-upload/server/content/files/160c47adb1f7fc---faborofinimikebowipuvip.pdfIn PDF document text
    • http://www.grupohk.com.br/wp-content/plugins/formcraft/file-upload/server/content/files/160949cb458782---47340940804.pdfIn PDF document text
    • https://unitedcardsolutions.com/wp-content/plugins/formcraft/file-upload/server/content/files/160c5f75039b09---nekufabul.pdfIn PDF document text
    • http://www.ascendercorp.com/In PDF document text
    • http://www.ascendercorp.com/typedesigners.htmlIn PDF document text
    • https://feedproxy.google.com/~r/1eyvgo/aqOO/~3/FevRqgeaUVY/uplcv?utm_term=focus+on+grammar+4+4th+edition+pdf+free+downloadPDF 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://scripts.sil.org/OFLIn PDF document text

Extracted artifacts 2

Files carved from inside the sample during analysis.

FilenameKindSourceSize
font_00_sfnt_off0000c820.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xC820 5704 bytes
SHA-256: cd8c45423a1b830588716f65672b0f15b5e96a883e9a4bd8fd520f895b14c766
font_01_sfnt_off0000db7c.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xDB7C 14624 bytes
SHA-256: cdef06b333e6596185ca5c0e672651fc6b15851653cbe4492b5637739aff93bd