Malicious PDF — malware analysis report

Static analysis result for SHA-256 fd31b4a3e8af7f0c…

MALICIOUS

PDF

82.2 KB Created: 2021-09-14 00:52:13 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-11-25
MD5: 5d19a5045715b71721eb762192089c3b SHA-1: c619df5355629692f72e9ae4b637f28ce13de928 SHA-256: fd31b4a3e8af7f0c7f89a4beb6d58d35ba72963a88a934efa7c6f2d09dd284a3
126 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment

The file is identified as malicious by ML classifiers and ClamAV, indicating a phishing or trojan threat. It contains numerous embedded URLs, many pointing to disposable domains, suggesting a link farm designed to redirect users. The PDF structure and the presence of embedded URLs are consistent with phishing lures or malware distribution campaigns.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9846

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://zh-huaxun.com/uploadfiles/files/51928289107.pdf In PDF document text
    • https://unitjaya.com/contents/files/kofefozebuninufe.pdfIn PDF document text
    • http://longvu.vn/Images_upload/files/47935098277.pdfIn PDF document text
    • http://montesantangelo.it/files/files/40032406417.pdfIn PDF document text
    • http://christmaslandint.com/userfiles/94704072745.pdfIn PDF document text
    • https://santa.sg/images/users/00000000/files/88272128516.pdfIn PDF document text
    • http://www.saito-ken.jp/userdata/file/79316172161.pdfIn PDF document text
    • http://slhospital.com/upload/fckeditor/file/gevoneje.pdfIn PDF document text
    • http://lycee-elm.info/userfiles/file/jopelofimuzurunog.pdfIn PDF document text
    • http://tpokebar.com/uploads/files/pewibevirerolofamit.pdfIn PDF document text
    • http://erisalaw-chicago.com/customer/3/d/9/3d947ad6ce2568d98b832ccf5548371bFile/53319042526.pdfIn PDF document text
    • http://nm-union.ru/ckfinder/userfiles/files/nojowe.pdfIn PDF document text
    • http://lamelove-zakryti.cz/userfiles/file/96682479138.pdfIn PDF document text
    • https://resicolor.com/upload/files/zuxinolarenukowareni.pdfIn PDF document text
    • https://pikhospital.com/ck_uploads/uploads/files/80625485450.pdfIn PDF document text
    • http://ingmarcofaedi.com/userfiles/files/23997640386.pdfIn PDF document text
    • http://sterenstein.ru/userfiles/file/58843963655.pdfIn PDF document text
    • http://355353.ru/userfiles/file/maxutugonazotupegijopif.pdfIn PDF document text
    • http://thai-apsproducts.com/file_media/file_image/file/vururolosifosukiguz.pdfIn PDF document text
    • http://ksnjl.com/userfiles/files/dilifepuvovifiduwo.pdfIn PDF document text
    • http://skup-laptopow.com/wp-content/plugins/formcraft/file-upload/server/content/files/16131bb0a532a3---14479319078.pdfIn PDF document text
    • http://fzcce.com/aimgs/uload/files/pesuvexutusokekeg.pdfIn PDF document text
    • http://swapnakoodu.com/fck_uploads/file/dinimuxajub.pdfIn PDF document text
    • http://sgyscom.com/upload_fck/file/2021-9-2/20210902080210693853.pdfIn PDF document text
    • https://independentmusicleague.com/wp-content/plugins/super-forms/uploads/php/files/e646f1aa3378e0067825eca7b7a75c22/dopojis.pdfIn PDF document text
    • https://beautyyaurient.com/editor_upload/file/55547330769.pdfIn PDF document text
    • https://feedproxy.google.com/~r/skout/mBVl/~3/3CAf4wW3hvY/uplcv?utm_term=how+to+set+up+automatic+text+reply+on+androidPDF 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_off0000db40.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xDB40 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
font_01_sfnt_off0000f352.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xF352 17816 bytes
SHA-256: e1ecc071b41732dfdcbfcd916a88b8d8ee843e69c5bee6ec70190fc1e46808ad
font_02_sfnt_off00012122.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x12122 11068 bytes
SHA-256: 176bcf83a05f3e14a782f00ee53df1d6fc75d92b7c5b6c4f6e7b3053ea5e8dc2