Malicious PDF — malware analysis report

Static analysis result for SHA-256 efbe90d7140f6f6f…

MALICIOUS

PDF

69.8 KB Created: 2021-09-30 16:21:02 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-10-26
MD5: ac27889ccfee82fac6df70c16719b406 SHA-1: 5cf5ea0573c1ada594f5e16cbeafaa8acdb796d4 SHA-256: efbe90d7140f6f6fc7e29635ea5e57c46e7ce63cf741a1926f35f9023a5554f5
126 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment

The file was detected as malicious by ClamAV and an ML classifier, indicating a high likelihood of malicious intent. The PDF contains numerous embedded URLs pointing to a link farm, suggesting a phishing or SEO manipulation tactic. While no scripts were explicitly extracted, the PDF structure and heuristic firings suggest it may leverage embedded JavaScript for malicious actions, such as redirecting users to potentially harmful sites.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9975

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://kachelofen-prommegger.at/nalewemonobetikebal.pdf In PDF document text
    • http://pobierzplik.pl/uploads/files/16428399699.pdfIn PDF document text
    • http://miet-boot.ch/images/uploadedimages/file/42317447575.pdfIn PDF document text
    • http://m-s-g.ru/userfiles/files/5905682712.pdfIn PDF document text
    • https://marjoyunlar.com/calisma2/files/uploads/24484311169.pdfIn PDF document text
    • http://thanhlamresort.vn/wp-content/plugins/formcraft/file-upload/server/content/files/16141f2f38fe81---64517945157.pdfIn PDF document text
    • http://xn--9p4b29dncp2cc6y.net/upload/fckeditor/file/22062665573.pdfIn PDF document text
    • http://universalestetic.com/userfiles/file/89372479237.pdfIn PDF document text
    • https://essuances.com/ckfinder/userfiles/files/67017229983.pdfIn PDF document text
    • https://divetechmarine.com/contents/files/puxumer.pdfIn PDF document text
    • http://avs-market.ru/admin/ckfinder/userfiles/files/10525513937.pdfIn PDF document text
    • http://cukiernia.eu/upload/files/28028316538.pdfIn PDF document text
    • http://golfvillageonline.com/userfiles/file/bijobelusur.pdfIn PDF document text
    • https://tourpon.kr/FileData/ckfinder/files/20210906_B5BC425375BE1DB0.pdfIn PDF document text
    • https://pbanerjeeservices.4digitmagic.com/userfiles/file/gijomilovomijanewekunes.pdfIn PDF document text
    • http://morard-mcf.fr/data/Files/32212862570.pdfIn PDF document text
    • http://autoservizimensi.it/images/fck/file/59255976428.pdfIn PDF document text
    • http://df-2.de/images/daten/file/wuzanodo.pdfIn PDF document text
    • http://flomojapan.com/upload/files/tilit.pdfIn PDF document text
    • http://ykzn8.com/upfiles/editor/files/votezoleroketulefedix.pdfIn PDF document text
    • http://ud2-140.com/files/jugajoboxutekidumexuwobu.pdfIn PDF document text
    • http://www.findvoters.com/userfiles/file/38251412913.pdfIn PDF document text
    • http://phutunggiahungoto.com/uploads/files/sifiditarujafasisakitag.pdfIn PDF document text
    • https://www.allterra.group/wp-content/plugins/super-forms/uploads/php/files/2e4638855fe7d7a690c13ff813a08e2f/59011133371.pdfIn PDF document text
    • https://feedproxy.google.com/~r/Uplcv/~3/BvfzZFkJO3s/uplcv?utm_term=five+nights+at+freddys+unblocked+gamesPDF 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_off0000b141.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xB141 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
font_01_sfnt_off0000c958.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xC958 11412 bytes
SHA-256: 19a1af3345e5c6aa9be47e701834858a019b6cdc0cfa49aea7ee4d9c577a5a99
font_02_sfnt_off0000e3e4.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xE3E4 14860 bytes
SHA-256: b74feae2be7c06f48256ee743c8c505eefa98015df774c2be0483678226451cb