Malicious PDF — malware analysis report

Static analysis result for SHA-256 fc8aac7fb1b0872a…

MALICIOUS

PDF

76.0 KB Created: 2021-09-14 09:47:24 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-10-14
MD5: e10a0d5053e323d014b4562428228adf SHA-1: 150ff9f3ffef8d81e7f168b18829b2e71eadb041 SHA-256: fc8aac7fb1b0872a09bd6fc4a123916c5cc4678451dabc8047eeb8ac029a5a4c
126 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment

The PDF contains numerous embedded links, many of which point to disposable domains and are structured as link farms, suggesting a phishing or malware distribution attempt. The ClamAV detection and ML classifier strongly indicate malicious intent. While no scripts were directly extracted, the PDF structure and embedded URLs are indicative of a malicious document designed to trick users into downloading further malicious content.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9948

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 http://mikailang.com/userfiles/file/20210912134819_1987081409.pdf In PDF document text
    • http://storemisr.com/uploads/files/fivibujekimoso.pdfIn PDF document text
    • http://pdww.ru/ckfinder/userfiles/files/72032276321.pdfIn PDF document text
    • http://ramenhajimetustin.com/uploads/files/sorigomaja.pdfIn PDF document text
    • http://www.sosonomo.com/ckfinder/userfiles/files/35532409268.pdfIn PDF document text
    • https://civilkontroll.hu/uploads/file/nizitarix.pdfIn PDF document text
    • https://digireg.org/upload/93384033186.pdfIn PDF document text
    • https://wspaperbag.com/userfiles/file/vuden.pdfIn PDF document text
    • https://lisacutler.com/wp-content/plugins/formcraft/file-upload/server/content/files/161316538b295a---kikafigot.pdfIn PDF document text
    • http://sparkpro.lv/content/file/46347936685.pdfIn PDF document text
    • http://mingzhicc.com/userfiles/files/28473275232.pdfIn PDF document text
    • https://istanajp.com/contents/files/visuxiluzalojutimemej.pdfIn PDF document text
    • https://maytinhdalat.vn/images/uploads/files/kapikisifufovizafudujub.pdfIn PDF document text
    • https://auditorescr.com/ckfinder/userfiles/files/xuzajometobekizuzifo.pdfIn PDF document text
    • https://millvalley.com/wysiwygfiles/file/85465495139.pdfIn PDF document text
    • https://afayl.com/userfiles/file/33945695442.pdfIn PDF document text
    • http://nadiadsa.org/userfiles/file/59796312273.pdfIn PDF document text
    • http://www.s-prom.si/fileupload/file/ralinuteximiwig.pdfIn PDF document text
    • http://hiro-seiko.com/upload/files/zexobiwogedadij.pdfIn PDF document text
    • http://www.kymkarajok.net/tiedostot/files/14654345196.pdfIn PDF document text
    • http://karlsbach.de/userfiles/files/bikebonuj.pdfIn PDF document text
    • https://fertilizerproductionprocess.com/d/files/85663314528.pdfIn PDF document text
    • http://vladjurnalist.ru/archive/file/rojogiminapobanuro.pdfIn PDF document text
    • http://atek-ent.com/upload/file/jinutelewaludasukuj.pdfIn PDF document text
    • https://feedproxy.google.com/~r/1eyvgo/aqOO/~3/S30rS-6n6vg/uplcv?utm_term=the+walking+dead+android+full+game+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_off0000c6bc.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xC6BC 10776 bytes
SHA-256: 7f0fc8134c6e80ea433b6d51dd72b66a7d4c7c8e88335b23cb156ce906bd912c
font_01_sfnt_off0000df20.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xDF20 16776 bytes
SHA-256: d1048529e6a08f4b81bc1c7598c3cd3fc749d70cfd98743ec9c887817b931fe6
font_02_sfnt_off00010a74.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x10A74 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1