Malicious PDF — malware analysis report

Static analysis result for SHA-256 6a5aa9364f785697…

MALICIOUS

PDF

69.4 KB Created: 2021-09-25 06:11:21 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-10-27
MD5: 69b6d38a7b904e5dbf5259faa1799cf0 SHA-1: 30aa077a88281ecda8fa6c904cc980e3a36e289b SHA-256: 6a5aa9364f785697d07b644a026d89a7f463c8ebff55a60fe3fc5c4fd29142ec
176 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment T1204.001 User Execution: Malicious Link

The PDF is identified as malicious by ClamAV and an ML classifier, and heuristics indicate it's an image-only lure designed to trick users into clicking external links. Many of these links point to compromised WordPress sites hosting similar PDF files, suggesting a phishing campaign. The document body is heavily obfuscated and unreadable, providing no direct clues to its specific purpose beyond the general phishing lure.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9975

Heuristics 7

  • ClamAV: Pdf.Phishing.Trojan-d2568dad23a94d95-d2568dad23a94d95-10044375-0 critical CLAMAV_DETECTION
    ClamAV detected this file as malware: Pdf.Phishing.Trojan-d2568dad23a94d95-d2568dad23a94d95-10044375-0
  • Image-only document with action trigger (screenshot lure) medium PDF_IMAGE_LURE
    PDF has 1 image(s), only 0 text block(s), carries a click-outward action, and is only 69 KB — typical shape of a phishing lure where a full-page screenshot hides a clickable button that launches or submits to an attacker URL.
  • 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 http://www.kindytennis.com/wp-content/plugins/formcraft/file-upload/server/content/files/1614125c0aa4cb---32802886754.pdf In PDF document text
    • http://hkwwta.org/userfiles/boburozegugabil.pdfIn PDF document text
    • http://www.logistiekverbeteren.nl/ckfinder/userfiles/files/6986840584.pdfIn PDF document text
    • https://acethamessecurity.co.uk/wp-content/plugins/super-forms/uploads/php/files/3ac30394fd0fd3174efcbc934af4861a/kexoxo.pdfIn PDF document text
    • http://gibisch.biz/files/files/turesuguwugaxudew.pdfIn PDF document text
    • http://wiskind.com/filespath/files/20210913213302.pdfIn PDF document text
    • http://eventologia.com/userfiles/files/19198378154.pdfIn PDF document text
    • http://bakoca.hu/files/file/rijozepoxof.pdfIn PDF document text
    • http://cainghienbinhduong.com/uploads/userfiles/file/91223848992.pdfIn PDF document text
    • http://chaodontuonglai.vn/uploads/ck_upload/files/gadivitaposo.pdfIn PDF document text
    • http://shiny-baby.com/fileimage/file/94323491842.pdfIn PDF document text
    • http://www.absolutecateringla.com/wp-content/plugins/formcraft/file-upload/server/content/files/16139efaae2aab---gubavibofekaf.pdfIn PDF document text
    • http://atlantichomeportugal.com/wp-content/plugins/formcraft/file-upload/server/content/files/1613979092a521---legalajejopufuduf.pdfIn PDF document text
    • http://lagerunda.it/public/upload/file/79238913547.pdfIn PDF document text
    • https://adrfarysz.pl/userfiles/file/wonepexagagegowologa.pdfIn PDF document text
    • http://lpc2529.com/piceditor/file/gejarotibozaduwuxul.pdfIn PDF document text
    • http://21cedu.com/pds/userfiles/files/34066768573.pdfIn PDF document text
    • https://gpagroup.in/wp-content/plugins/formcraft/file-upload/server/content/files/161346f06e6db2---40235119072.pdfIn PDF document text
    • https://encouragingmath.com/wp-content/plugins/super-forms/uploads/php/files/2f61b20a30d9118a75cfc1ace66ed2aa/wakixononulojisut.pdfIn PDF document text
    • http://arohitourandtravels.com/userfiles/file/83415212829.pdfIn PDF document text
    • http://sevvalturizm.com/rsm/files/64477266767.pdfIn PDF document text
    • http://raczcsalad.hu/files/12187926910.pdfIn PDF document text
    • https://audit-advisers.com/userfiles/file/95620543456.pdfIn PDF document text
    • http://theclelandgroup.com/img/upload/file/lowofilepamukil.pdfIn PDF document text
    • https://feedproxy.google.com/~r/1eyvgo/aqOO/~3/DOqCt-cVA4I/uplcv?utm_term=how+do+i+enable+developer+optionsPDF 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_off0000b3a7.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xB3A7 10668 bytes
SHA-256: bfea981c294ef109b3a7c7c002c33f735a453000705d5b9570a19a7a36084c77
font_01_sfnt_off0000cbf9.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xCBF9 14160 bytes
SHA-256: 66ab9063f755296cc85dddf7e9fd20f3e6c57405cfc149869017b4533297ac8d
font_02_sfnt_off0000ef81.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xEF81 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1