Malicious PDF — malware analysis report

Static analysis result for SHA-256 a1b342df7182c4b1…

MALICIOUS

PDF

69.0 KB Created: 2021-09-29 14:49:17 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-11-25
MD5: c76f7b917f6000f675a6e125122f57b6 SHA-1: af17f9e54dcd9bb7800d20ba9b3497ad38135e5b SHA-256: a1b342df7182c4b19fe41b2a3506e82068d2056cbbf5f6fdf857bb5f365b88da
126 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment

The sample is a PDF file flagged by ML classifiers and ClamAV as malicious. It contains numerous embedded URLs pointing to various domains, suggesting a phishing or malware distribution campaign. The heuristic 'PDF_SEO_DISPOSABLE_LINK_FARM' indicates a large number of links on disposable hosting, reinforcing the malicious intent. No scripts were extracted, but the presence of many external URIs suggests the PDF's primary function is to redirect users to potentially harmful content.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9978

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://krisoc.ru/uplcv?utm_term=roblox+got+talent+sheets PDF link annotation
    • http://pallenberg-busreisen.de/uploads/files/60264882221.pdfIn PDF document text
    • http://jjburgerut.com/uploads/files/kiwiwajukifabilonem.pdfIn PDF document text
    • http://songdolandmarkcity.com/userfiles/file/27775474717.pdfIn PDF document text
    • http://tekizolasyon.com/ckfinder/userfiles/files/79475860623.pdfIn PDF document text
    • http://areaengineeringsrl.eu/userfiles/files/45389695542.pdfIn PDF document text
    • http://zussobrance.sk/grafika/dokumenty/43522072794.pdfIn PDF document text
    • https://www.nvsrolko.org/ckfinder/userfiles/files/34150366481.pdfIn PDF document text
    • https://tonwen.org/userfiles/file/bumaduravipamim.pdfIn PDF document text
    • https://akdenizokullari.k12.tr/wp-content/plugins/super-forms/uploads/php/files/q36o83dir9l1pu67u097ol0osm/tomuvisidegar.pdfIn PDF document text
    • https://pecsikult.hu/files/file/7550791546.pdfIn PDF document text
    • https://www.studioline.ie/ckfinder/userfiles/files/tetuvaxajosufedipibojabim.pdfIn PDF document text
    • http://hfnhsw.com/upload/files/94287374014.pdfIn PDF document text
    • https://phr4u.com/files/xitobizaromixofazotaz.pdfIn PDF document text
    • https://dacoma.ro/wp-content/plugins/formcraft/file-upload/server/content/files/16138402a7d46c---tenomibojivudosufularim.pdfIn PDF document text
    • https://bauarch.bg/files/41065175321.pdfIn PDF document text
    • https://artenika.pl/fck/file/74725322993.pdfIn PDF document text
    • http://creativeindustries.ru/uploads/userfiles/file/lexebezemipab.pdfIn PDF document text
    • http://ristorantebiscione.com/userfiles/files/tuzut.pdfIn PDF document text
    • http://euromarkcreations.com/new/fck_img/file/furanovemexasegikizo.pdfIn PDF document text
    • http://privateeducation.sg/verzsape/demo/upload/admin/files/gibozosinetufodemaze.pdfIn PDF document text
    • http://straub-online.ch/userfiles/files/sifurubifebi.pdfIn PDF document text
    • http://soosanfix.com/upload/fckeditor/file/37439526796.pdfIn PDF document text
    • https://rockyhotelsgroup.com/uploaded/files/63551524544.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_off0000b09e.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xB09E 14948 bytes
SHA-256: 49acd763bb7c142e09dfef449e813566e267d649e107e902e6fe931e4eafa8fb
font_01_sfnt_off0000d648.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xD648 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
font_02_sfnt_off0000ee5f.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xEE5F 10484 bytes
SHA-256: 5dfb276400ba005ebd4a31fa438c29b1c74a98a2ab6cc4d77b407107fe4ff47d