Malicious PDF — malware analysis report

Static analysis result for SHA-256 c6d5eb3b38b4b5b8…

MALICIOUS

PDF

70.7 KB Created: 2021-09-26 01:57:14 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3)
MD5: 36684b8df4973f22802fc09caf3e6290 SHA-1: b1c8fe43cea5db0b6636e41eed2bd978aa257e5d SHA-256: c6d5eb3b38b4b5b81fb54a9583f51f40a339523f83a6b14e3e87346ac156c68d
156 Risk Score

Malware Insights

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

The PDF file was detected as malicious by ML classifiers and ClamAV, indicating a phishing or trojan payload. It functions as a link farm, directing users to multiple external URLs hosted on potentially compromised or disposable domains. The presence of numerous links, including those pointing to compromised CMS upload storage, suggests an attempt to distribute malicious content or phish for credentials.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9947

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://archism.ru/uplcv?utm_term=what+the+most+populated+country
    • https://divanich96.ru/admin/ckfinder/userfiles/files/60355925854.pdf
    • https://bengalroys.com/ckfinder/userfiles/files/dogafinajefixeda.pdf
    • https://spirit-legend-enterprises.com/webroot/editor-uploads/files/53318773141.pdf
    • http://tropo-design.com/ckfinder/userfiles/files/dapipatudonifilu.pdf
    • http://beautifulmoda.com/userfiles/files/22572681089.pdf
    • https://www.elshandmadedesign.nl/ckfinder/userfiles/files/89150362071.pdf
    • http://phuketdriveschool.com/userfiles/file/zusezalerufumariwapew.pdf
    • http://dmkert.hu/files/file/fakixopusidala.pdf
    • https://realwebguys.com/wp-content/plugins/formcraft/file-upload/server/content/files/16132a5b723500---83572991421.pdf
    • https://fishboat.hr/files/29204193884.pdf
    • http://kolesnikov.pro/ckfinder/userfiles/files/18462518872.pdf
    • https://agribusiness.pk/wp-content/plugins/formcraft/file-upload/server/content/files/1614208d4e2a5f---27200620262.pdf
    • http://bakefruit.com/uploads/files/202109030357458963.pdf
    • https://mysilofr.mysilo.com/upload/ckfinder/files/8491203427.pdf
    • http://vevo.keresztessyoptika.hu/elemek/file/pikupunakopasinifo.pdf
    • http://screen.by/images/file/lejeruzosaz.pdf
    • https://e-tta.com/app/webroot/userfiles/files/17539157553.pdf
    • https://forumhotel.by/wp-content/plugins/super-forms/uploads/php/files/gvcrpj57jlh8p05i00nhdagra5/51985806730.pdf
    • https://ka-base.no/images_students/files/kulotisa.pdf
    • http://gemaeldeundobjekte.de/uploads/files/50653024872.pdf
    • http://pi-consulting.ch/download/komebiwapu.pdf
    • http://ufnk.fr/app/webroot/files/file/sunukewibiriposagevozufo.pdf
    • https://elsa-daulte.com/ckfinder/userfiles/files/35207940107.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_off0000b096.bin
696b09fd0b67f013b4ba26df305397b09a60ba4ef0183c33c5ecd6ed531d6d13
pdf-font-stream PDF embedded font (sfnt) at offset 0xB096 10896 bytes
font_01_sfnt_off0000c9a7.bin
cb31683bf75f388c46c801162050ae8f23c581c670954962f6e896a17da1593c
pdf-font-stream PDF embedded font (sfnt) at offset 0xC9A7 17360 bytes
font_02_sfnt_off0000f5cd.bin
9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
pdf-font-stream PDF embedded font (sfnt) at offset 0xF5CD 16792 bytes