Malicious PDF — malware analysis report

Static analysis result for SHA-256 a0b8130f395f1d76…

MALICIOUS

PDF

81.8 KB Created: 2021-09-20 09:35:00 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-10-23
MD5: 6a81c8ce7e818bde03092568ee2764b4 SHA-1: 2d83bbbe022078626ac4594c5fa545ca4b55be5a SHA-256: a0b8130f395f1d76ac65bcb8dff8ed5cda3712839cd995f06f6cf8c45a0b11f8
166 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment

The PDF contains numerous external links, with a high-confidence heuristic identifying a link to a potentially malicious URL. The ClamAV detection and ML classifier strongly indicate malicious intent, likely related to phishing or malware delivery. The document body is heavily obfuscated and unreadable, but the presence of embedded URLs and the overall structure suggest it's designed to redirect users to malicious content.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9974

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 to algorithmically-generated URL high PDF_RANDOM_URL_LINK
    PDF contains a clickable HTTP(S) link whose host looks algorithmically generated (pronounceable-random labels) and whose path/query carries a long high-entropy token. This is the randomized-redirector pattern of malspam phishing lures — the visible document is only a prompt — not a PDF parser vulnerability.
  • 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://vetportonaccio.it/userfiles/files/texosomini.pdf In PDF document text
    • https://ozanetiket.com/TasarimAcarnet/serhali/upload/files/norupefewiguvi.pdfIn PDF document text
    • http://xyr59.com/filespath/files/20210903081411.pdfIn PDF document text
    • http://vita24h.com/uploads/userfiles/file/33302998625.pdfIn PDF document text
    • https://spcinternational.in/ckfinder/userfiles/files/melakunaxejijedis.pdfIn PDF document text
    • https://holzhaus-suedtirol.it/wp-content/plugins/formcraft/file-upload/server/content/files/161445e6f3976d---mezawekot.pdfIn PDF document text
    • http://synowka.pl/galeria/file/surukopevimetotapazix.pdfIn PDF document text
    • https://jf-orvalho.pt/userfiles/file/12060349073.pdfIn PDF document text
    • http://robwalker.net/fckupload/file/7579332980.pdfIn PDF document text
    • http://etkenkalip.com/files/rodawezidelelo.pdfIn PDF document text
    • http://bakoca.hu/files/file/42682661344.pdfIn PDF document text
    • http://costanzolegal.com/customer/3/d/9/3d947ad6ce2568d98b832ccf5548371bFile/488513473.pdfIn PDF document text
    • https://xyoaa.org/sites/default/files/files/lazevorova.pdfIn PDF document text
    • http://cornucopiafrederick.com/uploads/files/31537644591.pdfIn PDF document text
    • http://herve-coiffure.ci/files/40725783566.pdfIn PDF document text
    • https://aimhc.com/userfiles/file/bebikirose.pdfIn PDF document text
    • http://technestudio.eu/userfiles/files/43936456548.pdfIn PDF document text
    • http://busangh.com/attfile/fckimg/file///20210914135114_1054596726.pdfIn PDF document text
    • https://ghadir-eng.com/userfiles/files/63950474843.pdfIn PDF document text
    • http://www.vitrierbxl.be/wp-content/plugins/formcraft/file-upload/server/content/files/161302ab8c2d09---pirawerijawegibabobarovu.pdfIn PDF document text
    • https://sssmri.com/ckfinder/userfiles/files/wigoru.pdfIn PDF document text
    • https://childrencareandliteracysociety.org/userfiles/files/sakewegadovivikujakufigoz.pdfIn PDF document text
    • https://chowdhurytourism.com/ckfinder/userfiles/files/92708183353.pdfIn PDF document text
    • http://jiachuankeji.com/upload_fck/file/2021-9-11/20210911064650956886.pdfIn PDF document text
    • https://feedproxy.google.com/~r/skout/mBVl/~3/ngfLrbzwjls/uplcv?utm_term=mortal+kombat+8+apk+downloadPDF 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_off0000d8c4.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xD8C4 18584 bytes
SHA-256: 3fc09bdaf7f24a7cded678702d3ea01a684045c5f6870d72228e5d7aed65704d
font_01_sfnt_off00010924.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x10924 10680 bytes
SHA-256: 9c8c037d596ad94e85009ad33ca95f9e11dde0453a4fd7f94cac348fd9aa37a5
font_02_sfnt_off0001217c.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x1217C 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1