Malicious PDF — malware analysis report

Static analysis result for SHA-256 0a2f3a78a02d208b…

MALICIOUS

PDF

74.5 KB Created: 2021-09-08 19:06:26 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3)
MD5: c639cf35dabf0461d6fa3ea1d9f70233 SHA-1: 99e0dae20e8afd1ce07b9707ba5c3474188c2046 SHA-256: 0a2f3a78a02d208bd86eba7c472152443bed3b49566cb8a30069edd8a37d5439
156 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment

This PDF file was flagged by multiple heuristics and an ML classifier as malicious, with ClamAV identifying it as a phishing trojan. The document functions as a link farm, containing numerous external URLs pointing to other PDF files, likely for SEO manipulation or to distribute further malicious content. While no scripts were explicitly extracted, the presence of multiple compromised CMS upload links and disposable hosting suggests a coordinated effort to host and distribute malicious files.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9953

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 http://xn--b1adrijbbb.xn--p1ai/upload_picture/xexuwasutigiwidetagofivez.pdf
    • http://friluftsgruppen.se/wp-content/plugins/formcraft/file-upload/server/content/files/1613058fbe3019---zepub.pdf
    • https://tiemhoahaibara.com/data/dulieu/files/nuzadepimoma.pdf
    • https://nolimitscenter.be/peausitive/images/FCKeditor/file/12215197267.pdf
    • http://www.sunarsurdurulebilir.com/wp-content/plugins/super-forms/uploads/php/files/jm0f0strl98g22idq2n19s5ss3/pobidewemegi.pdf
    • http://awkontrakt.pl/ckfinder/userfiles/files/68591556418.pdf
    • http://vhz.cz/user-files/lavaripiropebud.pdf
    • http://xn--b1amishc2fb.xn--p1ai/ckfinder/userfiles/files/15538237339.pdf
    • http://humansharehouse.com/userData/board/file/lefamugozapiw.pdf
    • https://staffxrecruitment.com/wp-content/plugins/super-forms/uploads/php/files/9c5877f13ae10a783ce69002e2808622/vijud.pdf
    • https://padservhosting.com/userfiles/file/nosadenakemodesojajon.pdf
    • http://rigdrilling.org/userfiles/file/memolivenuso.pdf
    • http://nicolalazzarotto.com/userfiles/files/13429178754.pdf
    • http://www.driftime.ee/wp-content/plugins/formcraft/file-upload/server/content/files/16136cc9e7c8c6---givozexubumozuvas.pdf
    • http://robvancampen.nl/userfiles/file/32096610126.pdf
    • http://www.cavice.fi/tiedostot/files/592117539.pdf
    • https://klingende-zeder.de/wp-content/plugins/formcraft/file-upload/server/content/files/16136805ff118f---20994505744.pdf
    • http://permanentnimakeup-brno.cz/userfiles/files/35361076725.pdf
    • https://alfa-clining.ru/wp-content/plugins/super-forms/uploads/php/files/07a68de305c28e164c533779b9f79b4e/77699265094.pdf
    • http://mevlanaasm.com/resimler/files/9173347135.pdf
    • http://trumoi-khutrung.com/upload/files/buxixijevinilax.pdf
    • http://arenabilardo.com/data/_files/tiwev.pdf
    • https://www.ediliziaindustriale.com/wp-content/plugins/formcraft/file-upload/server/content/files/161333635086ce---42462483994.pdf
    • https://feedproxy.google.com/~r/skout/mBVl/~3/zMnd8XtcwSM/uplcv?utm_term=command+your+morning+by+cindy+trimm+pdf
    • http://www.w3.org/1999/02/22-rdf-syntax-ns#
    • http://purl.org/dc/elements/1.1/
    • http://ns.adobe.com/pdf/1.3/
    • http://ns.adobe.com/xap/1.0/
    • http://ns.adobe.com/xap/1.0/mm/
    • http://ns.adobe.com/xap/1.0/rights/
    • http://dejavu.sourceforge.net
    • http://dejavu.sourceforge.net/wiki/index.php/License

Extracted artifacts 3

Files carved from inside the sample during analysis.

FilenameKindSourceSize
font_00_sfnt_off0000c154.bin
2c47b7a92f6ba7efb5a89931b54065370bc6d47303298046a3f0bad568679d32
pdf-font-stream PDF embedded font (sfnt) at offset 0xC154 16552 bytes
font_01_sfnt_off0000eb39.bin
9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
pdf-font-stream PDF embedded font (sfnt) at offset 0xEB39 16792 bytes
font_02_sfnt_off00010350.bin
0da16008ae27ebc2434f1295d15eba897c605fdb8338939beb52737136df98a9
pdf-font-stream PDF embedded font (sfnt) at offset 0x10350 11004 bytes