Malicious PDF — malware analysis report

Static analysis result for SHA-256 de8a8e0ce3c65aa7…

MALICIOUS

PDF

73.6 KB Created: 2021-09-21 00:58:27 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-10-31
MD5: 84daa87b2beabb0250364374ce63bdce SHA-1: c2c7ee3f1f272277a51faa10d389bf0e7c02aa98 SHA-256: de8a8e0ce3c65aa73341719e25391a39e5052b5432c821bb17ab81c341ae1772
186 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment

The PDF contains a high-confidence heuristic indicating a link to an algorithmically-generated URL, which is a common tactic for phishing and malware distribution. The ML classifier also strongly flagged this PDF as malicious. The presence of numerous embedded URLs, many of which are suspicious, further supports the malicious intent. The document body is heavily obfuscated and appears to be generated by wkhtmltopdf, suggesting it's not intended for human readability but rather to host malicious links.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9907

Heuristics 7

  • ClamAV: Pdf.Phishing.Trojan-d2528dad23a95d95-d2528dad23a95d95-10044376-0 critical CLAMAV_DETECTION
    ClamAV detected this file as malware: Pdf.Phishing.Trojan-d2528dad23a95d95-d2528dad23a95d95-10044376-0
  • PDF link to algorithmically-generated URL high PDF_RANDOM_URL_LINK
    PDF contains a clickable HTTP(S) link whose host looks algorithmically generated (pronounceable-random labels) and whose path/query carries a long high-entropy token. This is the randomized-redirector pattern of malspam phishing lures — the visible document is only a prompt — not a PDF parser vulnerability.
  • Malformed active-content stream length medium PDF_MALFORMED_EXPLOIT_STREAM_LENGTH
    A PDF stream that carries active/exploit-looking content has a declared /Length that does not match the recovered stream body. Malformed stream boundaries and length mismatches are common parser-evasion/supporting evidence around Reader exploit streams.
  • 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://milliondollardesiclub.com/upload_files/featured/files/fekopeporabewexekusibi.pdf In PDF document text
    • http://copingconversations.com/userfiles/file/kibepapu.pdfIn PDF document text
    • http://emannsltd.com/userfiles/kulusali.pdfIn PDF document text
    • http://moscow-vernisage.com/files/files/tijovumuposixe.pdfIn PDF document text
    • http://onlinetradeshow.ir/uploads/files/xevabudisutuwamekibuzikox.pdfIn PDF document text
    • https://rubyyadav.com/nbloom/fckuploads/file/jinenezilew.pdfIn PDF document text
    • http://tainanrup.longi.tw/uploadfiles/files/20210908_142910_7089.pdfIn PDF document text
    • http://asid.rw/userfiles/file/40971502791.pdfIn PDF document text
    • https://trexanh.net/upload/files/25247947732.pdfIn PDF document text
    • https://k31szmq42-nu28.com/contents/files/joranuleturazifunufa.pdfIn PDF document text
    • https://avukatwebsitesi.trakyasoft.com/upload/files/97566600080.pdfIn PDF document text
    • http://retailcop.ca/files/sonekoxerexutejunuwemajob.pdfIn PDF document text
    • http://www.slenderclub.cz/ckfinder/userfiles/files/tatugulelesov.pdfIn PDF document text
    • http://rtm-plus.com/ckfinder/userfiles/files/15557401013.pdfIn PDF document text
    • http://dirpub.org/editor/ckfinder/userfiles/files/medov.pdfIn PDF document text
    • https://ipssecurityconsultants.com/ckfinder/userfiles/files/24368016082.pdfIn PDF document text
    • https://hasekei.jp/userfiles/file/redokakuxuvol.pdfIn PDF document text
    • https://superiorservicesandsolutionsfl.com/nbloom/fckuploads/file/vijijas.pdfIn PDF document text
    • https://actaviaserica.org/board/file/files/26186154984.pdfIn PDF document text
    • https://bibonatura.com/ckfinder/userfiles/files/wakipajiduw.pdfIn PDF document text
    • http://protech.com.ng/wp-content/plugins/formcraft/file-upload/server/content/files/1613a9978c9803---guviw.pdfIn PDF document text
    • https://tidurmalam2.com/contents/files/ririwirutosuziwejeso.pdfIn PDF document text
    • https://maximatrimony.com/ckfinder/userfiles/files/77093195270.pdfIn PDF document text
    • http://machinesupplier.cn/data/product/file/202199_191945_783.pdfIn PDF document text
    • http://capesociety.ca/uploads/files/62343492616.pdfIn PDF document text
    • http://www.caribbeandentist.com/wp-content/plugins/formcraft/file-upload/server/content/files/1613b6859f1026---xelujopuxosagoxatadoxo.pdfIn PDF document text
    • https://maciejabramowicz.pl/upload/files/file/91542387427.pdfIn PDF document text
    • https://feedproxy.google.com/~r/Uplcv/~3/BkSY9tpko7c/uplcv?utm_term=online+line+dancingPDF 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_off0000bdb7.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xBDB7 17460 bytes
SHA-256: f9695de6634c81499b37a7c4328ee96643bff36b9f1899cd6f25a31d80e2de79
font_01_sfnt_off0000ea60.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xEA60 10084 bytes
SHA-256: 2c76e1f657aa3d3abdf0da160e2382f57a0f40130e695818e8b3fc720d11e80f
font_02_sfnt_off000100ba.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x100BA 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1

Open this report in the interactive analyzer, or submit your own file for analysis.