Malicious PDF — malware analysis report

Static analysis result for SHA-256 74d825b9a5f7d65c…

MALICIOUS

PDF

72.7 KB Created: 2021-09-29 09:47:25 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-10-26
MD5: 8244a263fcce81752b5dc8c9fcaac33b SHA-1: 57fab2d6276339bff43116f99ea1fcf067b2feab SHA-256: 74d825b9a5f7d65c5b94c29ccc2eb02e1b6d9c23e0ec45fb66b9d045919d6d6d
66 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment

The PDF contains numerous embedded URLs, with a high-confidence ML classifier flagging it as malicious. The heuristic 'PDF_SEO_DISPOSABLE_LINK_FARM' indicates a pattern of using many distinct hosts for links, suggesting a link farm or redirection scheme. While no scripts were explicitly extracted, the nature of PDF exploitation often involves embedded JavaScript for malicious actions, hence T1059.007 is included as a likely technique.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9840

Heuristics 4

  • 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://terracell.pt/images/file/99591412545.pdf In PDF document text
    • http://xn--80aafbjcazdrhzgiddbbcsg4l.xn--p1ai/pict/file/36678880149.pdfIn PDF document text
    • http://ltptech.vn/uploads/userfiles/file/dilupigugarurixenugeki.pdfIn PDF document text
    • http://investin-khj.ir/ckfinder/userfiles/files/25408657390.pdfIn PDF document text
    • http://library.nesdb.go.th/ic/admin/ckfinder/userfiles/files/72818372362.pdfIn PDF document text
    • https://exam11.menapoint.com/app/webroot/upload/files/zobabejukonetifi.pdfIn PDF document text
    • https://groupburuemas2.com/contents/files/kapidowalezujefir.pdfIn PDF document text
    • http://nyitotthaz.hu/userfiles/files/tuvitefu.pdfIn PDF document text
    • http://baobianhkhang.com/upload/files/lidifovimumajokajib.pdfIn PDF document text
    • https://maturana.cl/upload/file/pawepiketigetokewiwusijur.pdfIn PDF document text
    • http://baharemadinah.com/wp-content/plugins/formcraft/file-upload/server/content/files/1612f9228149df---33742171387.pdfIn PDF document text
    • http://vswet.ru/f/mosilukupurabejiran.pdfIn PDF document text
    • http://pcccphucvinh.com/upload/files/21741660144.pdfIn PDF document text
    • http://sportsbettingconsultants.net/cote_dor_import/admin/ckfinder/userfiles/files/58066489018.pdfIn PDF document text
    • http://kaies.net/upfiles/file/bikujawapuzidi.pdfIn PDF document text
    • http://smartpaintingplus.com/userfiles/files/tonafiguxasorara.pdfIn PDF document text
    • https://xn--64-mlcufjjaii0l.xn--p1ai/wp-content/plugins/super-forms/uploads/php/files/96c7740fa7b35f147e1ec29d8379986c/bofofofamunokidowazo.pdfIn PDF document text
    • https://speakingparrot.com/upload/ckfinder/files/11386651666.pdfIn PDF document text
    • http://hometextiles-consultant.com/ckfinder/userfiles/files/murawokezupu.pdfIn PDF document text
    • http://xn--80aer5aza.xn---42-5cdakyymnnb9ake1az.xn--p1ai/ckfinder/userfiles/files/68453163639.pdfIn PDF document text
    • http://tlumacz-lipno.pl/pdrzewiecki/files/xasewowazewazaparodewi.pdfIn PDF document text
    • https://etadelloro.it/images/file/79119095412.pdfIn PDF document text
    • https://redac.ch/upload/11681594885.pdfIn PDF document text
    • http://ky-auto.com/uploadfile/files/lurifimoboluzamesek.pdfIn PDF document text
    • http://7166867.ru/ckfinder/userfiles/files/bigage.pdfIn PDF document text
    • https://novsport.com/content/File/2156697876.pdfIn PDF document text
    • https://feedproxy.google.com/~r/1eyvgo/aqOO/~3/3vuEKuznOb8/uplcv?utm_term=what+is+the+collective+noun+of+starsPDF 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_off0000b616.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xB616 18376 bytes
SHA-256: 8305ad4e4a50c6d1a885bd8330a1424dc7a5d724c04cd7d2285d03ca549ae353
font_01_sfnt_off0000e4e1.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xE4E1 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
font_02_sfnt_off0000fcf8.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xFCF8 10592 bytes
SHA-256: 2e7524f333e94fd513330c54d1ccbcbebb9cd45d086bd944cc490a1af5f372dd