Malicious PDF — malware analysis report

Static analysis result for SHA-256 a559aef295229d7f…

MALICIOUS

PDF

72.3 KB Created: 2021-09-19 02:51:53 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-10-16
MD5: cb33c199f035023355ab1f9c0da92336 SHA-1: df4cb2c69d269b2139769ebea19ddf85d189dd16 SHA-256: a559aef295229d7f42a4611180ad7c8327f28a9957aa1233cd9a74cdfcd90538
156 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment

The PDF contains multiple embedded URLs, several of which point to compromised or disposable hosting, indicating a link farm designed to redirect users. The ML classifier and ClamAV detection strongly suggest malicious intent, likely phishing or malware delivery. While no scripts were directly extracted, the PDF structure and embedded links are consistent with techniques used to distribute malicious content.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9965

Heuristics 6

  • ClamAV: Pdf.Phishing.Trojan-d2568dad23a94d95-d2568dad23a94d95-10044375-0 critical CLAMAV_DETECTION
    ClamAV detected this file as malware: Pdf.Phishing.Trojan-d2568dad23a94d95-d2568dad23a94d95-10044375-0
  • PDF link farm points to compromised-WordPress upload storage medium PDF_COMPROMISED_CMS_UPLOAD_LINK_FARM
    PDF contains multiple clickable links, across many distinct hosts, whose targets are random-slug files parked in the upload directories of vulnerable WordPress form plugins (FormCraft, Super Forms). This is the hallmark of the 'free document/template' SEO phishing PDF family, which ranks for search queries and routes users into payload/redirect chains hosted on compromised sites. The PDF itself carries no exploit — the risk is the linked destinations.
  • 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://noithatkuongthinh.com/uploads/files/mafaxitawaketoraneneza.pdf In PDF document text
    • http://bamor.org/userfiles/file/jixatogemewemabepevuxapi.pdfIn PDF document text
    • http://www.astmalek.cz/obrazky/file/kalonibuxirepivobuvigez.pdfIn PDF document text
    • http://chagatea.ru/wp-content/plugins/super-forms/uploads/php/files/148d11adcb62d1634191c4cbaf95d8c9/60366099255.pdfIn PDF document text
    • http://test.uebersetzungen-nesselberger.de/wp-content/plugins/formcraft/file-upload/server/content/files/16134db4d9ad60---10145537840.pdfIn PDF document text
    • http://foto-preiss.at/upload_files/files/fabagolosoxe.pdfIn PDF document text
    • http://ingmontagna.com/userfiles/files/lumij.pdfIn PDF document text
    • http://sanarina.de/ckfinder/userfiles/files/zagoxonunokatov.pdfIn PDF document text
    • http://lamgi.pl/ckfinder/userfiles/files/didimigabulusis.pdfIn PDF document text
    • https://onecre.com/images/content/files/fitava.pdfIn PDF document text
    • http://vitalenzyme.com/uploads/fckupload/file/ziredokanasimobexi.pdfIn PDF document text
    • http://nnk.gr/wp-content/plugins/formcraft/file-upload/server/content/files/1612eacb888acb---36297404024.pdfIn PDF document text
    • http://zeci.nl/im/image/fuwinumunitisirejasowexu.pdfIn PDF document text
    • http://huerural.com/uploads/image/files/61515692580.pdfIn PDF document text
    • https://webhosting4.net/media/file/43961896147.pdfIn PDF document text
    • https://www.inter-tube.co.uk/wp-content/plugins/super-forms/uploads/php/files/88c01eaf36a1aa80605a397edc448962/7249231772.pdfIn PDF document text
    • http://timnhanhonline.vn/upload/files/49981814422.pdfIn PDF document text
    • https://www.meditech.cz/ckfinder/userfiles/files/40111092624.pdfIn PDF document text
    • http://www.lebedosapartotel.com/data/yukle/files/88190919323.pdfIn PDF document text
    • https://negaratoto.com/contents/files/pusafovujiwifamuroxir.pdfIn PDF document text
    • http://gtlfuelmarine.com/userfiles/file/95265236502.pdfIn PDF document text
    • https://www.weboonline.com/ckfinder/userfiles/files/58995060386.pdfIn PDF document text
    • https://feedproxy.google.com/~r/1eyvgo/aqOO/~3/ngfLrbzwjls/uplcv?utm_term=roblox+royale+high+cheatsPDF 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_off0000b779.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xB779 10804 bytes
SHA-256: 566bb4c460c72da521f05c07cfdb3b5ba4eee6e534b7d556313a66edaf645a5c
font_01_sfnt_off0000d09d.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xD09D 16836 bytes
SHA-256: 3ea89a83817efe4583cc0cf92f25686556d5881cbd823094d709b85509fc3e00
font_02_sfnt_off0000fc1f.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xFC1F 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1