Malicious PDF — malware analysis report

Static analysis result for SHA-256 dd13af752aafb683…

MALICIOUS

PDF

84.3 KB Created: 2021-07-21 12:52:22 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-09-14
MD5: ddbdd6716874e8fa58afecd74b5a56ba SHA-1: 8c31fed0310e382796537e57acdc73c4975472de SHA-256: dd13af752aafb683429952c2d594fea21ee231eabeb51843ba9dd31469357db5
156 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment T1204.002 Malicious Link

The PDF contains numerous links pointing to compromised WordPress sites, identified by the 'PDF_SEO_DISPOSABLE_LINK_FARM' and 'PDF_COMPROMISED_CMS_UPLOAD_LINK_FARM' heuristics. The ML classifier and ClamAV also flagged this PDF as malicious, with ClamAV specifically identifying it as 'Pdf.Phishing.Trojan'. The primary attack pattern involves directing users to malicious content via these links, likely for phishing or further malware delivery.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9992

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://siyata.co.il/wp-content/plugins/formcraft/file-upload/server/content/files/16074f8a1bf6ea---rakilazejuzipin.pdf In PDF document text
    • http://www.hollyskauaicondo.com/wp-content/plugins/formcraft/file-upload/server/content/files/160a0f52507286---472210325.pdfIn PDF document text
    • https://bishopsalamatkhokhar.org/userfiles/file/kavixukotuxazefiw.pdfIn PDF document text
    • http://artecgroupservices.com/imagenes/file/kotubeware.pdfIn PDF document text
    • https://marcuspietrek.de/MARCUS/files/file/93436274052.pdfIn PDF document text
    • http://albatrossmrn.com/konadnew/userfiles/file/sexomepumazasugazuzobawo.pdfIn PDF document text
    • http://www.cargeacrew.com.br/wp-content/plugins/formcraft/file-upload/server/content/files/160e23df53a7bf---dugemanapemagurizuzi.pdfIn PDF document text
    • http://abington1964.com/clients/865474/File/jobexowazasunukiz.pdfIn PDF document text
    • http://beloit1962.com/clients/8/83/8368a4f838dea3176655029ae9e337da/File/54434323415.pdfIn PDF document text
    • https://fellowpeo.com/wp-content/plugins/super-forms/uploads/php/files/91bf16829dcd227e4ecceca27e666dc5/vatilakewetama.pdfIn PDF document text
    • http://kripasec.com/userfiles/file/58477757459.pdfIn PDF document text
    • http://www.next-conseil.fr/wp-content/plugins/formcraft/file-upload/server/content/files/16074fd1795b72---pudixowawonudazovax.pdfIn PDF document text
    • https://evocative.ru/wp-content/plugins/formcraft/file-upload/server/content/files/1609d41ba7ec4a---lalulatil.pdfIn PDF document text
    • https://studiovizia.com/webroot/img/content/files/45630539057.pdfIn PDF document text
    • http://xn--o39a91gvwm83kbsn.com/FileData/ckfinder/files/20210612_209C39D91806F88D.pdfIn PDF document text
    • https://sv-fin.ru/wp-content/plugins/super-forms/uploads/php/files/bcf11b9f39e2081238679aa8fc6ca8b6/5136400815.pdfIn PDF document text
    • http://rosniyom.com/userfiles/files/jejovuzosusewipivit.pdfIn PDF document text
    • https://www.hagensmarketing.com/wp-content/plugins/formcraft/file-upload/server/content/files/160a65c5c80f24---fajetopakovaf.pdfIn PDF document text
    • https://feedproxy.google.com/~r/1eyvgo/aqOO/~3/FevRqgeaUVY/uplcv?utm_term=how+many+cups+of+water+in+5+quartsPDF 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_off0000e4c8.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xE4C8 11168 bytes
SHA-256: 74c435f59a0974596963bbf47d1d7199f2b3c427ed1d63302de6536670b126ff
font_01_sfnt_off0000fef8.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xFEF8 17284 bytes
SHA-256: 5d9098bacaaf7c91071501196a900f5b4de3bdf22b0abed31a4f2c04fb6e77d6
font_02_sfnt_off00012c60.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x12C60 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1