Malicious PDF — malware analysis report

Static analysis result for SHA-256 fb28fe15b0c15e43…

MALICIOUS

PDF

111.4 KB Created: 2021-09-02 23:35:28 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-10-16
MD5: 629bbcce4f52a47e9147f0daa99353c7 SHA-1: bad6b21a35f4ade757828c3103aeb57c8a8c7554 SHA-256: fb28fe15b0c15e435d0c31d4ac9457886d923398947a7e2407d2f118c2c1dd70
164 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment T1203 Exploitation for Client Execution

The file is identified as malicious by ClamAV and an ML classifier, indicating a high likelihood of malicious intent. The PDF contains a link farm pointing to compromised CMS uploads, suggesting a phishing or malware distribution lure. The presence of external URIs and the 'ML_NYX_PDF_MALICIOUS' heuristic further support this assessment.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9966

Heuristics 7

  • 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.
  • 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 http://mko-yug.ru/wp-content/plugins/super-forms/uploads/php/files/dbb4a0dbd7c06a95779671519fd9f7b1/19901808558.pdf In PDF document text
    • http://izumrud38.com/ckfinder/userfiles/files/66196143307.pdfIn PDF document text
    • https://akproauto.com/nbloom/fckuploads/file/wezol.pdfIn PDF document text
    • http://kliknetezde.cz/admin/obrazky/file/11903203740.pdfIn PDF document text
    • http://heatherjansch.com/ckfinder/userfiles/files/15283688124.pdfIn PDF document text
    • http://hsound.ro/images/custom/file/dibageve.pdfIn PDF document text
    • https://realschoolspirit.com/scauserfiles/files/fanevo.pdfIn PDF document text
    • https://www.ewdel.cz/ckfinder/userfiles/files/45840786597.pdfIn PDF document text
    • http://mecaniquekd.ca/upload/file/melefaj.pdfIn PDF document text
    • http://cgt-fo-csc.fr/wp-content/plugins/formcraft/file-upload/server/content/files/160800b6348622---katotezuvesimi.pdfIn PDF document text
    • https://miaousland.fr/ckfinder/userfiles/files/zeminuresofiwabi.pdfIn PDF document text
    • http://eurekaelearning.com/upload/news/file/50233800604.pdfIn PDF document text
    • https://beaumont-residence.com/wp-content/plugins/super-forms/uploads/php/files/42lo0k0qm90frt80vpscdbg5l4/sajulumekagupire.pdfIn PDF document text
    • https://ashleymongolia.mn/uploads/files/nofiwajifenif.pdfIn PDF document text
    • http://profisystem.ro/wp-content/plugins/formcraft/file-upload/server/content/files/1609c45a061c6f---supekisonuwa.pdfIn PDF document text
    • http://www.ausafrica.co.za/wp-content/plugins/formcraft/file-upload/server/content/files/16092dd12ce738---95859010313.pdfIn PDF document text
    • https://maidintown.co.uk/wp-content/plugins/super-forms/uploads/php/files/52fc1b8becfbd9d1453b1d465c85498c/nadinegalenes.pdfIn PDF document text
    • http://stphilomenaonline.org/userfiles/file/butidoxetatevamefapu.pdfIn PDF document text
    • http://triumphtoday.org/wp-content/plugins/formcraft/file-upload/server/content/files/1607126e0ea410---gesixureduruz.pdfIn PDF document text
    • http://xpeedon.net/userfiles/file/20210829073427.pdfIn PDF document text
    • http://speakingaboutnetworking.com/ckfinder/userfiles/files/pewosemaxolota.pdfIn PDF document text
    • http://endustriyelkiralama.com/wp-content/plugins/super-forms/uploads/php/files/1lbri1atk80qpb7ofujlibc1ik/rudiverowifeduzat.pdfIn PDF document text
    • https://www.carlosfunes.es/wp-content/plugins/formcraft/file-upload/server/content/files/1608046e4e4c43---40704295784.pdfIn PDF document text
    • http://zeci.nl/im/image/825361429.pdfIn PDF document text
    • http://robwalker.net/fckupload/file/vutajemeruwepakufijowa.pdfIn PDF document text
    • https://feedproxy.google.com/~r/Uplcv/~3/1KS0DP0cxss/uplcv?utm_term=blood+relation+reasoning+tricks+in+english+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_off0001460c.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x1460C 11044 bytes
SHA-256: 6ebc2b044e63c7c4325dfc07dc055e3e797fb1037e2168ff33728f0018735fba
font_01_sfnt_off00015f7b.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x15F7B 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
font_02_sfnt_off0001778d.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x1778D 21076 bytes
SHA-256: 220e236fc0e3b5815d4a6f7a1bac23d71369c22f667efbadececd6dad9448379