Malicious PDF — malware analysis report

Static analysis result for SHA-256 63dd888bfda60d1d…

MALICIOUS

PDF

69.5 KB Created: 2021-10-01 04:18:51 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-10-31
MD5: 1636d18a44e74a4c00ce3f2854e0a58a SHA-1: f05b92bb26b75a5f841348c87c1d2be413434a60 SHA-256: 63dd888bfda60d1d3cc444ddecd6a52a892da910b9cf80d9b8c6f23f2ec3a7c0
156 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment

The file was detected as malicious by ML classifiers and ClamAV, indicating a high likelihood of malicious intent. It contains numerous external links, many hosted on compromised or disposable domains, suggesting a link farm designed to redirect users to malicious sites. The presence of PDF-specific heuristics like 'PDF_SEO_DISPOSABLE_LINK_FARM' and 'PDF_COMPROMISED_CMS_UPLOAD_LINK_FARM' further supports this, indicating the PDF's primary function is to act as a lure for external malicious content.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9975

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 https://allytemp.ru/uplcv?utm_term=aparted+apk+download PDF link annotation
    • http://lngpetro.com/userfiles/file/56519016041.pdfIn PDF document text
    • https://festivaldelmaridaje.com/sgi_userfiles/userfiles/files/rabukekenunuperegoregit.pdfIn PDF document text
    • http://special-pharma.com/upload/files/dijubuporuguvujexaso.pdfIn PDF document text
    • http://cuacongtudongbinhduong.com/upload/files/68938364795.pdfIn PDF document text
    • https://tucsonhomewindowtint.com/wp-content/plugins/super-forms/uploads/php/files/89bac1c421e76b32400821cf51b30a1f/20887063994.pdfIn PDF document text
    • http://knipia.com/userfiles/file/96523515449.pdfIn PDF document text
    • https://matras-matrasych96.ru/admin/ckfinder/userfiles/files/maxepuziretisatumesed.pdfIn PDF document text
    • https://smsenerji.com/resimler/files/fuleguvorosufamiror.pdfIn PDF document text
    • https://812423.qqtogeljackpot2.com/contents/files/34832906164.pdfIn PDF document text
    • https://kattliv.com/kattliv/admin/userfiles/file/6428071177.pdfIn PDF document text
    • http://cu-mbc.com/ckfinder/userfiles/files/31061574669.pdfIn PDF document text
    • https://www.novet.de/wp-content/plugins/formcraft/file-upload/server/content/files/161556dd54f6d6---24505139334.pdfIn PDF document text
    • http://easytravel63.ru/ckfinder/userfiles/files/vuketamatoxijulosenuta.pdfIn PDF document text
    • http://ihdbd.org/upload/files/83684661809.pdfIn PDF document text
    • https://asiquim.com/ckfinder/userfiles/files/29442229447.pdfIn PDF document text
    • http://a-xian-coat.com/uploads/files/202109110013413458.pdfIn PDF document text
    • https://otomatcilarmetal.com/otomat/upload/files/72513749067.pdfIn PDF document text
    • http://postelezmasivu-olomouc.cz/ckfinder/userfiles/files/49956555973.pdfIn PDF document text
    • https://lazeo.nl/userfiles/file/movabekawigobitag.pdfIn PDF document text
    • http://greenld.com/userfiles/gidezagag.pdfIn PDF document text
    • https://33mobility.net/uploads/files/jukekogozexoteteme.pdfIn PDF document text
    • https://brawlcall.com/ckfinder/userfiles/files/85249936545.pdfIn PDF document text
    • http://thebookmarkcafe.com/uploads/files/33541144182.pdfIn PDF document text
    • http://b40555.handyfriendship.com/upload/files/buzitananidazalitogabupo.pdfIn PDF document text
    • https://simovi.mx/wp-content/plugins/formcraft/file-upload/server/content/files/1613eb96ad20ab---gegumevopenizev.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_off0000b407.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xB407 14808 bytes
SHA-256: 92dfa69c8b545a536d1c4e8df72b3c5450c992cb3f06c9858201b3be201284c3
font_01_sfnt_off0000d8d6.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xD8D6 10284 bytes
SHA-256: 5395704399316e25ca5345162126f8a983cab6edfcd434f0f07e5217db52caae
font_02_sfnt_off0000f037.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xF037 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1