Malicious PDF — malware analysis report

Static analysis result for SHA-256 53070897d8d25988…

MALICIOUS

PDF

82.1 KB Created: 2021-09-01 09:01:36 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-11-25
MD5: dfb3b2896735be9d15c8e089de44e683 SHA-1: d4340ed20f48dd2ec4eea2bd2b6fe56647a0ce56 SHA-256: 53070897d8d259880a2999c124a73cfb0d80bfc21ac5bce066790301c50b92d2
156 Risk Score

Malware Insights

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

The PDF contains numerous embedded URLs, many of which point to compromised CMS uploads or disposable hosting, indicating a link farm designed to obscure the final destination. The ML classifier and ClamAV detection strongly suggest malicious intent, likely phishing or malware delivery. The presence of multiple compromised upload links and disposable hosting suggests an attempt to evade detection and analysis.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9988

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 http://sten.kr/club/data/userfiles/file/20210826093315.pdf In PDF document text
    • http://www.dr.schure.net/ckfinder/userfiles/files/womujeduzera.pdfIn PDF document text
    • https://hmv.ir/wp-content/plugins/formcraft/file-upload/server/content/files/1608089edd45c4---38444481256.pdfIn PDF document text
    • http://minerva-collection.net/files/files/bupazimezibe.pdfIn PDF document text
    • https://www.oasipizza.it/wp-content/plugins/formcraft/file-upload/server/content/files/160c96366d62a3---17925895532.pdfIn PDF document text
    • https://namastehealth.in/wp-content/plugins/super-forms/uploads/php/files/a9klevgttf2lbvnf52ea8mcqrp/laxedo.pdfIn PDF document text
    • http://inlikeflintlogistics.com/wp-content/plugins/formcraft/file-upload/server/content/files/160ae1983d38bc---dinululozatetegobafidu.pdfIn PDF document text
    • http://brain-sh.tw/upload/file/46039961270.pdfIn PDF document text
    • http://gamecoast.by/uploads/files/56744610338.pdfIn PDF document text
    • https://fortworthdental.net/cmsCart/upload/file/33229909930.pdfIn PDF document text
    • http://beateromer.com/bilder/file/31507622066.pdfIn PDF document text
    • http://xn----7sbab1bcaqplb0ccyi9d.xn--p1ai/files/file/63393410120.pdfIn PDF document text
    • http://kenshopvn.com/uploads/files/zogabax.pdfIn PDF document text
    • https://www.wikiwebagency.it/wp-content/plugins/super-forms/uploads/php/files/878a85d285229634d9c9dc4619995bbc/47782744511.pdfIn PDF document text
    • http://nuyewpilot.academy/wp-content/plugins/super-forms/uploads/php/files/4aa5793cb5fda3440bad4f70347650db/taxiwovokirexodamegiji.pdfIn PDF document text
    • http://share-world.tw/userfiles/file/35761032988.pdfIn PDF document text
    • http://quangcaosms.org/media/ftp/file/zotet.pdfIn PDF document text
    • https://vivekanandbawwa.com/userfiles/file/32146757454.pdfIn PDF document text
    • https://blackknowledge.com/wp-content/plugins/super-forms/uploads/php/files/be0a6c8a1d356bb36fc44dbad593f0cb/7444492253.pdfIn PDF document text
    • http://dienvietbac.com/uploads/files/marib.pdfIn PDF document text
    • http://0-50.ru/userfiles/file/82125716399.pdfIn PDF document text
    • http://phuocthuan.vn/images/pic/file/21627507390.pdfIn PDF document text
    • https://feedproxy.google.com/~r/skout/mBVl/~3/PmAiG5ZyT-k/uplcv?utm_term=assistant+speech+and+language+therapistPDF 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_off0000df27.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xDF27 16096 bytes
SHA-256: 7e04364322bb217fd3a045dcb6ea3a26e8fb834176b42d60a0158ba308313ebc
font_01_sfnt_off000108b9.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x108B9 10752 bytes
SHA-256: a67cf2f6de026c4581a59bc45f1a8fcd5fb5a1c47c82fb99d1d584168252a7fc
font_02_sfnt_off0001212f.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x1212F 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1