Malicious PDF — malware analysis report

Static analysis result for SHA-256 8425260612b35c4d…

MALICIOUS

PDF

74.5 KB Created: 2021-09-17 19:26:11 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-10-14
MD5: 9dd1a0b2773a432ef1acb5a97cb34590 SHA-1: 5e28885f687b6712b44554e5e9b05acb2bdb6c87 SHA-256: 8425260612b35c4d2a7f4f6522a9864e11bd1ef9ad7672f389208160ff980158
134 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment

The PDF contains embedded JavaScript, which is a common technique for exploiting vulnerabilities or redirecting users. The heuristic PDF_SEO_DISPOSABLE_LINK_FARM indicates the PDF is part of a link farm, suggesting a phishing or spam campaign. The ML classifier and ClamAV detection strongly indicate malicious intent, likely to redirect users to malicious sites hosted on domains like starcity-vinhomes.vn.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9947

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
  • 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.
  • Embedded JS stream low PDF_JS
    PDF references a /JS stream. Generic JavaScript is common in benign forms; specific dangerous APIs are scored by separate rules.
  • 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://starcity-vinhomes.vn/app/webroot/img/files/30899813271.pdf In PDF document text
    • https://siriusdynamics.com/assets/uploads/files/60648399387.pdfIn PDF document text
    • https://samavetpharm.com/userfiles/files/nuwuzoregu.pdfIn PDF document text
    • http://articolo17.it/siti/usr/foto/files/81271483339.pdfIn PDF document text
    • http://www.belladermeestetica.com.br/wp-content/plugins/formcraft/file-upload/server/content/files/1613daffdcc116---1206658860.pdfIn PDF document text
    • http://skidubravy.sk/spravca/ckfinder/userfiles/files/kefosinugarirodosus.pdfIn PDF document text
    • http://www.impactit.in/ckfinder/userfiles/files/39464641144.pdfIn PDF document text
    • http://nissanotogovap.vn/uploads/images/files/75458697448.pdfIn PDF document text
    • https://saftanton.dk/wp-content/plugins/formcraft/file-upload/server/content/files/16140e409e9474---namobovob.pdfIn PDF document text
    • http://rockhousemethod.com/ckfinder/userfiles/files/wuzibinekaledupegorokobi.pdfIn PDF document text
    • https://toolsatool.com/userfiles/files/57212286677.pdfIn PDF document text
    • http://ambvetsanprospero.eu/userfiles/files/dafegugu.pdfIn PDF document text
    • https://samsungklimamodelleri.com/upload/ckfinder/files/93735337224.pdfIn PDF document text
    • http://kyochonbuenapark.iorderfoods.com/uploads/files/dufolividarufaxenaragudag.pdfIn PDF document text
    • https://warsztatgdynia.pl/app/webroot/media/files/83510004733.pdfIn PDF document text
    • http://elai.kz/upload/2021/09files/210910023711863965pgix0.pdfIn PDF document text
    • https://ww150001.linebot.net/upfile/files/20210911041524.pdfIn PDF document text
    • https://netiko.ge/img/Data/file/62538179001.pdfIn PDF document text
    • http://rosg.net/sa_upload/userfiles/file/20210913164543.pdfIn PDF document text
    • http://tks-forever.com/upload/2021/09/04/file/48670960444.pdfIn PDF document text
    • http://pcccmiennam.com/media/ftp/file/tanikurukekojegiwusebo.pdfIn PDF document text
    • http://mebizstekla.ru/userfiles/file/lobibibilofitabuv.pdfIn PDF document text
    • http://scard.vn/app/webroot/uploads/files/xuzawiguwabovuremedasub.pdfIn PDF document text
    • http://musclecar-taps.com/js/upload/files/jikojisoza.pdfIn PDF document text
    • http://www.gamylai.vn/uploads/files/22456430700.pdfIn PDF document text
    • https://feedproxy.google.com/~r/Uplcv/~3/1xuhb7AK25c/uplcv?utm_term=cooking+mama+2+romPDF 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_off0000bf87.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xBF87 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
font_01_sfnt_off0000d79e.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xD79E 10252 bytes
SHA-256: 46da952a488ae024398a3586fde1ccfd8326cc24b72405317100b01c86ec0d33
font_02_sfnt_off0000eea4.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xEEA4 17780 bytes
SHA-256: 4bc9918d9ebae5ceac95dc2905c73ed00e2feecccb4705266a9ea4c585352543