Malicious PDF — malware analysis report

Static analysis result for SHA-256 52a7de90e0201e59…

MALICIOUS

PDF

85.7 KB Created: 2021-09-18 23:48:52 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-10-23
MD5: 012f765b08fa35051fdee5581529f7b2 SHA-1: 27d608cfc39362c9db98e0a70e7aaa87d5354a83 SHA-256: 52a7de90e0201e59bd83bbccef7bd5cc0b582c58f4941a5c604e3a7ff1913bd0
156 Risk Score

Malware Insights

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

The PDF file was flagged by ClamAV as Pdf.Phishing.Trojan and a machine learning classifier indicated a high probability of maliciousness. Numerous heuristics indicate the PDF functions as a link farm, with many embedded URLs pointing to compromised websites or disposable hosting, likely to obscure the final malicious destination. The presence of 'utm_term=free+email+android+app' in one URL suggests a lure related to email applications.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9988

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://pistant.ru/uplcv?utm_term=free+email+android+app PDF link annotation
    • http://hataylezzeti.com/resimler/files/kijonakutivixufaxaviwixed.pdfIn PDF document text
    • https://taechoclub.com/FileData/ckfinder/files/20210906_8FD8593AD0743A55.pdfIn PDF document text
    • http://clean-ecology.com/Upload/files/46990785433.pdfIn PDF document text
    • http://lawyersmarketingusa.com/user_upload_image/file/In PDF document text
    • http://labotinnghia.com/img/files/65427074864.pdfIn PDF document text
    • http://alessandrobelleseveterinario.eu/userfiles/files/dofod.pdfIn PDF document text
    • https://galaxytraining.examinationonline.com/files/76010652546.pdfIn PDF document text
    • http://cbelmira.com/wp-content/plugins/super-forms/uploads/php/files/1fc0cee31c68dcc95db27599dd293c32/57175368825.pdfIn PDF document text
    • http://stonebreaker.at/tomovo.pdfIn PDF document text
    • http://ljhalls.com/wp-content/plugins/super-forms/uploads/php/files/085fadac0890daed54d437e4d4a31d7b/ridakosisigezebewuxuvam.pdfIn PDF document text
    • http://vpecargo.com/userfiles/file/87141168026.pdfIn PDF document text
    • http://guitarenko.fr/img/files/kiligarejiwijepepimom.pdfIn PDF document text
    • http://mariautonoleggiomarsala.it/userfiles/files/bokusufuk.pdfIn PDF document text
    • http://huabulaw.com/uploadpic/2021-9/file/2021090508555273499.pdfIn PDF document text
    • https://www.bluegreenshouseboats.in/wp-content/plugins/formcraft/file-upload/server/content/files/1613caec6b16e1---99731501244.pdfIn PDF document text
    • https://afayl.com/userfiles/file/73743783920.pdfIn PDF document text
    • https://network-italia.com/file/61160576158.pdfIn PDF document text
    • https://franchise-vietnam.com/app/webroot/img/files/39624805164.pdfIn PDF document text
    • https://valleyrentals.com/userfiles/file/kukotuvaro.pdfIn PDF document text
    • https://aglogistics-bo.net/userfiles/file/meker.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_off0000edb0.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xEDB0 17308 bytes
SHA-256: 51ef6fe582422df524b9eb706f58558dff4a631424faedfd2a146f8708efad07
font_01_sfnt_off00011a77.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x11A77 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
font_02_sfnt_off0001328e.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x1328E 10264 bytes
SHA-256: f93b1251aea26469dee4b9b9c39fee38228adfd1eafdee8d576d2975829bf7ca