Malicious PDF — malware analysis report

Static analysis result for SHA-256 657f62ebdf213be7…

MALICIOUS

PDF

78.2 KB Created: 2021-09-02 14:07:25 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-10-23
MD5: 147d542246888501c5d1a9a7d81a5171 SHA-1: 8b73110183a21ef621067718a392ba348fada197 SHA-256: 657f62ebdf213be797e12aa6b53af77b31066e7b20c3456fa88e585e04de72f7
156 Risk Score

Malware Insights

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

This PDF was flagged by a machine learning classifier and ClamAV as malicious, indicating a high likelihood of malicious intent. The heuristics reveal it functions as a link farm, directing users to multiple external URLs hosted on compromised or disposable domains. These links are likely intended to facilitate phishing attacks or distribute further malware.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9911

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://mandarinusa.com/userfiles/file/1626488708.pdf In PDF document text
    • http://thanhlamresort.vn/wp-content/plugins/formcraft/file-upload/server/content/files/1611d719541efb---sigufonevimuvifafuxapox.pdfIn PDF document text
    • http://bioscipublisher.com/files/upfiles/file/fomuruweri.pdfIn PDF document text
    • http://www.ecostroyservis.ru/File/56827051879.pdfIn PDF document text
    • https://dmddsgn.com/wp-content/plugins/super-forms/uploads/php/files/31b6225399c3f5afe08bd9b11b29a714/xesitizekivive.pdfIn PDF document text
    • https://alsultantrading.ae/userfiles/files/fepuxodawazoj.pdfIn PDF document text
    • http://www.ondebiz.com/userfiles/file/8893848808.pdfIn PDF document text
    • http://51www.org/uploadfile/file/dd421be0e20364b3f02005472fdb767a.pdfIn PDF document text
    • http://marinaxaraes.com.br/ckfinder/userfiles/files/6225970489.pdfIn PDF document text
    • http://www.pics4us.de/userfiles/file/53565328490.pdfIn PDF document text
    • http://ophtalmic-overnight.fr/wp-content/plugins/formcraft/file-upload/server/content/files/160fd63d487815---60969316410.pdfIn PDF document text
    • http://machin.kr/userData/board/file/marerugibowisak.pdfIn PDF document text
    • https://vetranhtuongmamnon.vn/wp-content/plugins/super-forms/uploads/php/files/3r025t0njestg1f35125aedv0t/rumamoronutiwasupe.pdfIn PDF document text
    • http://sad-azov.ru/wp-content/plugins/super-forms/uploads/php/files/9b2f0a912aa7d4af5fed5ded5d54f012/80004772574.pdfIn PDF document text
    • https://anakmeong.com/contents/files/37105120105.pdfIn PDF document text
    • http://castudio.eu/userfiles/files/kodavupawesonuw.pdfIn PDF document text
    • http://kondicionery-krasnogorsk.ru/upload_picture/file/45626781120.pdfIn PDF document text
    • https://trsbarriersdirect.com/wp-content/plugins/super-forms/uploads/php/files/tofha548ra5a0mv7grueunb8fo/94272023285.pdfIn PDF document text
    • https://lightupalife.org.uk/wp-content/plugins/formcraft/file-upload/server/content/files/16110ce2e9eba2---31565419487.pdfIn PDF document text
    • https://mojer.bg/files/43762271353.pdfIn PDF document text
    • http://cnmrobotics.com/files/files/lotapepanoniwuwaxi.pdfIn PDF document text
    • http://propertiesforrent.com/userfiles/file///94369739767.pdfIn PDF document text
    • https://hoanghaie.com/Images_upload/files/881779009.pdfIn PDF document text
    • http://foto-klub.dk/userfiles/file/bupenaniwotolejav.pdfIn PDF document text
    • http://ural-kip.ru/admin/ckfinder/userfiles/files/20492649676.pdfIn PDF document text
    • http://worldnaturalfood.com/image/upload/File/17082319506.pdfIn PDF document text
    • https://aimhc.com/userfiles/file/68884165674.pdfIn PDF document text
    • https://feedproxy.google.com/~r/1eyvgo/aqOO/~3/A3Ryygt5BCM/uplcv?utm_term=dental+primary+tooth+trauma+guide+pdfPDF 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_off0000cbe1.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xCBE1 10992 bytes
SHA-256: 8fb8e21d0634291ec11db3846a1ffa81c2868246bfb78b92def13b8b60724e1f
font_01_sfnt_off0000e500.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xE500 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
font_02_sfnt_off0000fd12.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xFD12 17536 bytes
SHA-256: 8888e355e8fe9c7708ff75e6964fba086be8f175e195ffdde1f1a31d28997765