Malicious PDF — malware analysis report

Static analysis result for SHA-256 433b865fa3cf1c82…

MALICIOUS

PDF

79.7 KB Created: 2021-09-05 17:05:38 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-10-05
MD5: 0e9f49a1b035957b908a9a9c320bd56e SHA-1: 23ce455055e56d443ee4516ff4676a84e02fdfba SHA-256: 433b865fa3cf1c82d33b1a3c78d638a01736929a51b3a94060ad67c1578da17f
156 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment

This PDF file was flagged by multiple heuristics and a machine learning classifier as malicious, with ClamAV identifying it as a phishing trojan. It contains a link farm pointing to numerous domains, many of which appear to be compromised WordPress sites or disposable hosting, suggesting an attempt to obscure the ultimate destination. The primary purpose appears to be redirecting users through these links, likely to a phishing page or to download a secondary payload.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9949

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://synerhu.ru/uplcv?utm_term=combine+pdf+files+to+single+pdf+online PDF link annotation
    • https://www.techsrollout.com/wp-content/plugins/formcraft/file-upload/server/content/files/160b1640845e16---bogatolu.pdfIn PDF document text
    • http://novichiha.ru/pic/file/59987555807.pdfIn PDF document text
    • https://envida-nieuws.nl/bsb_website/upload_fck/file/pazefiwafewelijilege.pdfIn PDF document text
    • http://herium.net/FileData/ckfinder/files/20210713_14816A3671DAA38A.pdfIn PDF document text
    • https://www.travelticket.com.au/wp-content/plugins/super-forms/uploads/php/files/4m76guhr0cn9vvvr0n0hvaqccu/58248435317.pdfIn PDF document text
    • https://transport-vehicules.fr/userfiles/file/vagupinifiwilalalijol.pdfIn PDF document text
    • http://drvision.org/wp-content/plugins/formcraft/file-upload/server/content/files/1609eeb0a344c3---jorifepalipilenuwawi.pdfIn PDF document text
    • http://i-harmonics.com/upload/files/bumiduzemunutuw.pdfIn PDF document text
    • http://hnc2.com/userfiles/file/57596594693.pdfIn PDF document text
    • http://www.alwaysflorida.com/wp-content/plugins/formcraft/file-upload/server/content/files/160b27df6ee45f---laxufaruba.pdfIn PDF document text
    • http://kaufdeinauto.de/wp-content/plugins/formcraft/file-upload/server/content/files/16083e59047b5e---jimepud.pdfIn PDF document text
    • http://bazatalty.pl/wp-content/plugins/super-forms/uploads/php/files/25e95fee8c878e4ceefde201029567ac/puzojobivesarofajenup.pdfIn PDF document text
    • https://www.rydalmereprestige.com.au/wp-content/plugins/super-forms/uploads/php/files/5hugb7ktnqfhm70br9uljnbs0c/62537598955.pdfIn PDF document text
    • http://www.sevenchurchestour.net/seven/wp-content/plugins/formcraft/file-upload/server/content/files/1607bbe232e774---muritakazu.pdfIn PDF document text
    • http://proxima-design.cz/files/file/jewenomememovili.pdfIn PDF document text
    • http://kap-group.com/ckfinder/userfiles/files/2140936487.pdfIn PDF document text
    • http://fittbike.hu/files/file/rujij.pdfIn PDF document text
    • https://vizzzio.ru/wp-content/plugins/super-forms/uploads/php/files/5ff41dd5167608d7eeed598ba1d8a3bb/timatawok.pdfIn PDF document text
    • http://drivingschool-brno.eu/files/30699647146.pdfIn PDF document text
    • https://www.havanasalsa-dance-tours.com/wp-content/plugins/super-forms/uploads/php/files/779dc14a7057d189f337a04cc0d87e7c/62936218285.pdfIn PDF document text
    • https://senzedigicraft.com/wp-content/plugins/super-forms/uploads/php/files/6aaceb210e61216f1925eb9693a08901/54285866660.pdfIn PDF document text
    • http://greenbrier101.com/userimages/jetelofiru.pdfIn PDF document text
    • http://azizavacanze.com/userfiles/files/28466735516.pdfIn PDF document text
    • http://rocincorporated.com/domain.com/images/dynamic_pages/file/75797509206.pdfIn PDF document text
    • http://biolabsrl.org/userfiles/files/sodenozavusokemano.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_off0000d5e4.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xD5E4 10752 bytes
SHA-256: 98a914cc1349db15864b74b2311d1f088fb41a25a271c6c0922c0e1b5483131a
font_01_sfnt_off0000ee27.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xEE27 16524 bytes
SHA-256: c3444235b0f86d5da4d0a0e233a80e24254373e414185e2826e0645b1b793385
font_02_sfnt_off000118f6.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x118F6 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1