Malicious PDF — malware analysis report

Static analysis result for SHA-256 bcf1b23a7037a814…

MALICIOUS

PDF

84.1 KB Created: 2021-09-04 23:23:21 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-10-07
MD5: e1b1a47a9a552be705c9051eb5a4ee3a SHA-1: 015ee9b9a962ba0ab72d444ff0a0f27bf7516f8b SHA-256: bcf1b23a7037a814333d066b43cdf8393950f7d68c40bb72e982c9838353a749
164 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment

The file was detected as malicious by ClamAV and an ML classifier, indicating a high likelihood of malicious intent. Heuristics identified it as a link farm pointing to potentially compromised CMS uploads and disposable hosting, suggesting a phishing or malware distribution lure. The presence of embedded URLs, including one with a 'utm_term' parameter, further supports the attack pattern of directing users to external malicious sites.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9972

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.
  • Fake invoice / payment lure low SE_INVOICE_LURE
    Document contains invoice or payment language paired with an action verb — useful context when combined with link, macro, or attachment indicators
  • 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://garglob.ru/uplcv?utm_term=harga+mesin+serut+es+batu+manual+swan PDF link annotation
    • https://rhagro.com.mx/wp-content/plugins/super-forms/uploads/php/files/b2b3548cea5d73f3d3ca817ae1883aed/vagarumikujedep.pdfIn PDF document text
    • http://www.kocay.com.tr/wp-content/plugins/formcraft/file-upload/server/content/files/1609c85c2162f6---64636996638.pdfIn PDF document text
    • https://dichvuhappyhouse.com/upload/files/zevevubewibapa.pdfIn PDF document text
    • https://aymexco.ro/ckfinder/userfiles/files/fadup.pdfIn PDF document text
    • https://newat.ru/wp-content/plugins/super-forms/uploads/php/files/8297bb8817edd744bf8ebde92478d874/libesifaxukejivibidaras.pdfIn PDF document text
    • https://www.criteriainvest.com.br/wp-content/plugins/super-forms/uploads/php/files/kvar2kagcha0ntahmk63d6ustt/79072363486.pdfIn PDF document text
    • http://www.linkkorea.co.kr/wp-content/plugins/formcraft/file-upload/server/content/files/16077d86497e22---67621403087.pdfIn PDF document text
    • https://www.siemers-deutschmann.de/wp-content/plugins/super-forms/uploads/php/files/o6thiv6n0h2ft9cj48g6i26mtg/witekigesidavureliwimodux.pdfIn PDF document text
    • http://www.northeastmarquees.com/wp-content/plugins/super-forms/uploads/php/files/b6ac512d05c75ecf864f0f7726ae803b/dosuwebutuzo.pdfIn PDF document text
    • https://ahi.com.ua/wp-content/plugins/super-forms/uploads/php/files/24ced1e543cb3362c8e11beb627614b4/42224625838.pdfIn PDF document text
    • http://ziepniekkalns.lv/wp-content/plugins/formcraft/file-upload/server/content/files/1606f59ec7e15c---rikokurusedozajeriguk.pdfIn PDF document text
    • https://www.mii.net/wp-content/plugins/super-forms/uploads/php/files/56eabcddac7fca133e03b1848adaf065/tobimuvawemefulabiwi.pdfIn PDF document text
    • https://alves.bg/ckfinder/userfiles/files/75864587129.pdfIn PDF document text
    • https://oknoplus-omsk.ru/wp-content/plugins/super-forms/uploads/php/files/01f2d5e03c7d8e1939a6151988e2e478/zovonalawawosazuvoxab.pdfIn PDF document text
    • http://cokhihoangvinh.com/uploads/userfiles/file/67452601268.pdfIn PDF document text
    • https://www.tctnanotech.com/wp-content/plugins/super-forms/uploads/php/files/81fb0b48d704a78a670f1c1feaebd930/86555355396.pdfIn PDF document text
    • https://orkhaconstruction.com/wp-content/plugins/super-forms/uploads/php/files/sja76bllivg065p97ovisol07v/vonunikili.pdfIn PDF document text
    • http://yuseigachi.nl/wp-content/plugins/formcraft/file-upload/server/content/files/1609e5f5d55569---zukaripotebazudutupetukug.pdfIn PDF document text
    • https://drlanda.hu/user/file/zavap.pdfIn PDF document text
    • https://patriot.ch/wp-content/plugins/super-forms/uploads/php/files/s365mgrqs3mb3kdbnu83jg56jg/rugepitajilelivazakizi.pdfIn PDF document text
    • http://zs.tom.ru/jsplugins/ckfinder/userfiles/files/81596142600.pdfIn PDF document text
    • 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_off0000e3bb.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xE3BB 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
font_01_sfnt_off0000fbd2.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xFBD2 10648 bytes
SHA-256: 316b9f8fbdf15bc87db47a5b41b66f3b46a467d69172b15c3f2af38b88fa0668
font_02_sfnt_off00011429.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x11429 18292 bytes
SHA-256: c2d3832ef408432a6be1ff4f5a9ed76286b66f0de1dea95faa6dedb4c4fcf550