Malicious PDF — malware analysis report

Static analysis result for SHA-256 5aed653c79018edd…

MALICIOUS

PDF

70.3 KB Created: 2021-09-26 09:14:22 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-10-26
MD5: 91d771b086d9030a6e45ebc83273f925 SHA-1: 6a47fe72ea6515f2f3df7ae939dfc28fbd5d111b SHA-256: 5aed653c79018edd1786caddf291e7aaa0b6368539ccf23eafbea4c9bfc44d0c
156 Risk Score

Malware Insights

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

This PDF file was identified as malicious by ML classifiers and ClamAV, indicating a phishing or trojan-like nature. It functions as a link farm, with numerous embedded URLs pointing to potentially compromised WordPress sites and other disposable hosting. These links likely serve to redirect users to malicious payloads or phishing pages, a common tactic for initial compromise.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9975

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 http://www.linkkorea.co.kr/wp-content/plugins/formcraft/file-upload/server/content/files/1614d0ad2580d4---gitibekexela.pdf In PDF document text
    • http://klubalfa.org/img/userfiles/file/96391137607.pdfIn PDF document text
    • http://oa30us.com/userfiles/file/jifimez.pdfIn PDF document text
    • https://cincia.ro/ckfinder/userfiles/files/faxaromitemez.pdfIn PDF document text
    • http://bumsnab.ru/uploads/files/22387593116.pdfIn PDF document text
    • http://email-database.info/userfiles/file/luwokosar.pdfIn PDF document text
    • http://madinagirls.com/easydo%20v2.00/files/uploads/12560365165.pdfIn PDF document text
    • http://eatatrudy.com/uploads/files/84448052818.pdfIn PDF document text
    • http://entone.es/wp-content/plugins/super-forms/uploads/php/files/30583b3ffd2070046555b8164bff94b9/98685561054.pdfIn PDF document text
    • http://bkht.vn/userfiles/file/16300125033.pdfIn PDF document text
    • http://anshan56.cn/userfiles/file/16305844621970637385.pdfIn PDF document text
    • http://anabakorea.jp/userfiles/file/80229829698.pdfIn PDF document text
    • http://songhandiban.com/uploadfile/file/2021091514021473499.pdfIn PDF document text
    • http://thaimassageboy.com/ckfinder/userfiles/files/mafoxapenuledetalitaruke.pdfIn PDF document text
    • http://mos-craciun-inchiriere.ro/fckfiles/file/tonekerowixevukev.pdfIn PDF document text
    • https://forkidsvietnam.vn/wp-content/plugins/super-forms/uploads/php/files/i21qsbjho90vnabn8vmdboqi15/xowafejo.pdfIn PDF document text
    • http://archbot.pl/files/file/77411772392.pdfIn PDF document text
    • http://odesignlab.ru/admin/ckfinder/userfiles/files/junevigofuzutot.pdfIn PDF document text
    • https://vicareyou.com/userfiles/file/zamijo.pdfIn PDF document text
    • http://suspensionestg.mx/userfiles/file/nukutaboxugat.pdfIn PDF document text
    • http://www.prunay-en-yvelines.fr/ckfinder/userfiles/files/17545918016.pdfIn PDF document text
    • http://prefinancovaniehypoteky.sk/res/file/xijegabevabibogudezezif.pdfIn PDF document text
    • http://chithanhplastics.com/uploads/userfiles/file/kiwadujutetefuke.pdfIn PDF document text
    • https://sooryasales.com/uploads/file/xuxiwojopu.pdfIn PDF document text
    • https://feedproxy.google.com/~r/skout/mBVl/~3/BvfzZFkJO3s/uplcv?utm_term=dungeon+keeper+2+for+androidPDF 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_off0000b133.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xB133 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
font_01_sfnt_off0000c945.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xC945 15844 bytes
SHA-256: 327911e9062b6f5d46f0afcc06f5bc6eb7a804ff5ad7793bfaa8759d251043a8
font_02_sfnt_off0000f139.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xF139 10676 bytes
SHA-256: 6292e5b270996848e1089626bded2e83e2d9a52d0f270d0065eac093a4a0663d