Malicious PDF — malware analysis report

Static analysis result for SHA-256 accb9b6af01d8c18…

MALICIOUS

PDF

81.3 KB Created: 2021-09-19 04:19:27 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-10-16
MD5: e136efd9af5ccb742757fd2d79d33b3b SHA-1: 59bffe461a4a69b6de8adde73b98a5a9260454de SHA-256: accb9b6af01d8c18a8d8cc2ea8dc25e277ee268e85ee25b20526bc99acf8c9be
126 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment

The PDF contains numerous embedded URLs, many of which point to disposable hosting and are part of a link farm, a common tactic for phishing and malware distribution. The heuristic 'PDF_SEO_DISPOSABLE_LINK_FARM' specifically flags this behavior. The ML classifier and ClamAV detection strongly indicate malicious intent, likely related to phishing or trojan delivery.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9955

Heuristics 5

  • ClamAV: Pdf.Phishing.Trojan-d2568dad23a94d95-d2568dad23a94d95-10044375-0 critical CLAMAV_DETECTION
    ClamAV detected this file as malware: Pdf.Phishing.Trojan-d2568dad23a94d95-d2568dad23a94d95-10044375-0
  • 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://oniceh.ru/uplcv?utm_term=sms+backup+%26+restore+apk+download PDF link annotation
    • https://bnbtravels.com/ckfinder/userfiles/files/41612901365.pdfIn PDF document text
    • http://rlponder.com/customer/3/d/9/3d947ad6ce2568d98b832ccf5548371bFile/zelijobim.pdfIn PDF document text
    • http://isleford.com/filespath/files/20210917211432.pdfIn PDF document text
    • https://cambodiadriverservice.com/userfiles/file/71391807014.pdfIn PDF document text
    • https://factorysales.com/userfiles/files/5886367764.pdfIn PDF document text
    • https://airin.lv/images/userfiles/file/lizase.pdfIn PDF document text
    • http://cartonwrappingmachine.com/userfiles/file/48857619061.pdfIn PDF document text
    • http://luligang.com/ckfinder/userfiles/files/8033474748.pdfIn PDF document text
    • http://lsmtrontractor.com/upfiles/file/20210902214746.pdfIn PDF document text
    • https://greenfuturevietnam.com/Upload/files/rebaxo.pdfIn PDF document text
    • https://xo-sound.ru/userfiles/file/34688000913.pdfIn PDF document text
    • http://foodzipo.com/uploads/userfiles/files/kapatovilitapo.pdfIn PDF document text
    • http://pc580.cn/upload_fck/file/2021-9-1/20210901225117254808.pdfIn PDF document text
    • http://currycornersugarland.com/admin/images/file/sonenamabunopokawetepukol.pdfIn PDF document text
    • https://velvetskin.pl/wp-content/plugins/super-forms/uploads/php/files/ecd69dc4fd96dccc13481371d9eed1e6/sawamutoveragirowawova.pdfIn PDF document text
    • http://shamayachts.com/upload/file/94909041010.pdfIn PDF document text
    • http://gomientrung.vn/uploads/image/files/53486705362.pdfIn PDF document text
    • http://abpaluso.com/upload/file/mozidorididisali.pdfIn PDF document text
    • https://zweefvlieg.net/userfiles/file/gadilu.pdfIn PDF document text
    • https://californiaoptionsrealestate.com/wp-content/plugins/super-forms/uploads/php/files/161c2aad1b370018b370db51d167503c/mubowitisenuzowogazukidok.pdfIn PDF document text
    • https://enilubricant.hoakhanh.vn/uploads/image/files/73637458511.pdfIn PDF document text
    • http://labonguyenhoang.com/img-chamthi/files/78919377619.pdfIn PDF document text
    • http://trust-law-firm.com/userfiles/file/20210917155734_942916660.pdfIn PDF document text
    • http://espokebar.com/uploads/files/buxexemijowosirujakevolaj.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_off0000dc7a.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xDC7A 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
font_01_sfnt_off0000f491.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xF491 10248 bytes
SHA-256: de2fa12bd4495e333fc8bffdabdce9fcfc64ff607ce81bf4a9fce5813e8be185
font_02_sfnt_off00010b68.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x10B68 17104 bytes
SHA-256: f50c5471bfc1bea3a15346cf3bac74d2b4d97c10c3c4a440cf8563a086f7e611