Malicious PDF — malware analysis report

Static analysis result for SHA-256 a59aaf23fcb6aa2b…

MALICIOUS

PDF

79.2 KB Created: 2021-09-10 01:22:58 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-10-14
MD5: 9d5cc4bbea80e773f10a775443771ce1 SHA-1: 3a791d28499c7456ea27b69c41cec3c4a2e3e830 SHA-256: a59aaf23fcb6aa2b0a0223d705a069232397d9c574dada2b2ede5e686042e006
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, specifically as a phishing trojan. It contains a large number of embedded URLs, many pointing to disposable domains, indicating a link farm designed to redirect users. While no scripts were explicitly extracted, the PDF structure and the presence of numerous external links suggest an attempt to lure users to malicious sites, likely for phishing or further malware delivery.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9949

Heuristics 5

  • ClamAV: Pdf.Phishing.Trojan-d2528dad23a95d95-d2528dad23a95d95-10044376-0 critical CLAMAV_DETECTION
    ClamAV detected this file as malware: Pdf.Phishing.Trojan-d2528dad23a95d95-d2528dad23a95d95-10044376-0
  • 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://gruntbudowa.pl/files/file/vejujon.pdf In PDF document text
    • https://digitaluzaktanegitim.com/calisma2/files/uploads/54259865348.pdfIn PDF document text
    • http://ore-processing.ru/d/files/biginivekajozo.pdfIn PDF document text
    • https://anitt.in/ckfinder/userfiles/files/37586487714.pdfIn PDF document text
    • http://racecross.com/upload/edito_fckeditor/file/zuzofobidugukavatuzez.pdfIn PDF document text
    • http://monthclean.com/uploads/files/202109060603503778.pdfIn PDF document text
    • http://podwierzba.eu/ckfinder/userfiles/files/41035886014.pdfIn PDF document text
    • http://harringtonandlombardi.com/customer/3/d/9/3d947ad6ce2568d98b832ccf5548371bFile/labexilarilijotibawekimu.pdfIn PDF document text
    • http://oumkua.com/userfiles/file/64743213027.pdfIn PDF document text
    • http://n2nnetworks.com/files/others/relidadiveritutilaxe.pdfIn PDF document text
    • http://library.nesdb.go.th/ic/admin/ckfinder/userfiles/files/nanerodema.pdfIn PDF document text
    • http://www.iqubz.com/wp-content/plugins/formcraft/file-upload/server/content/files/16136f54c058bf---kavazonoziligudutaxomusaj.pdfIn PDF document text
    • https://testgit.begurholidays.com/uploads/userfiles/files/90997511941.pdfIn PDF document text
    • http://visit-pune.com/userfiles/file/girutazig.pdfIn PDF document text
    • http://tcihk.com/userfiles/jelavomeg.pdfIn PDF document text
    • http://opalbiosciences.com/wp-content/plugins/formcraft/file-upload/server/content/files/16137b6499025c---9229461999.pdfIn PDF document text
    • http://southerncross-ex.com/images/blog/file/95534928748.pdfIn PDF document text
    • http://innotack.com/userfiles/files/xixemojuvetumagit.pdfIn PDF document text
    • http://amuseonline.com/absite/userfiles/file/newasamozosunorawex.pdfIn PDF document text
    • http://njchemland.com/upload/files/48025569074.pdfIn PDF document text
    • http://pizzeria-millemiglia.de/app/webroot/img/editor/file/digojidemelilapov.pdfIn PDF document text
    • https://dunakanyarfesto.hu/ckfinder/userfiles/files/10786636450.pdfIn PDF document text
    • http://ediliziaunoaventi.com/userfiles/files/47456076887.pdfIn PDF document text
    • https://profipreklady.cz/www/ckfinder/userfiles/files/kipezixalotijaganowedo.pdfIn PDF document text
    • http://ud2-140.com/files/wonomakedatoxopiresatefof.pdfIn PDF document text
    • https://feedproxy.google.com/~r/1eyvgo/aqOO/~3/BkSY9tpko7c/uplcv?utm_term=my+player+apkPDF 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_off0000d583.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xD583 16844 bytes
SHA-256: cbf2abdfaaac7be79e02ee7fc98a3eec4051f2b871aa1939f5337adff4bbf9f4
font_01_sfnt_off000101c1.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x101C1 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
font_02_sfnt_off000119d7.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x119D7 9864 bytes
SHA-256: 9bb4a49d398d94b8fe841fa627bc1a6312c6ed1157a4997d1fdf0f31af91f470