Malicious PDF — malware analysis report

Static analysis result for SHA-256 edc4b611d7307e4b…

MALICIOUS

PDF

97.3 KB Created: 2021-07-02 12:28:16 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3)
MD5: b6b5e9fee7c6ada37465a2e38051f798 SHA-1: f53695e13656ea32a67a110ac29f04bc74403af0 SHA-256: edc4b611d7307e4b1ce863a51d7607b38da0ff0da2d982b3543d3297e818230a
156 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment T1204.002 Malicious Link

The PDF contains numerous embedded links, many of which point to compromised WordPress installations, indicating a phishing or link-farming scheme. The ML classifier and ClamAV detection strongly suggest malicious intent, likely to redirect users to malicious websites. No scripts were extracted, but the heuristic firings are sufficient to classify this as a malicious PDF.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9936

Heuristics 6

  • 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 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://nowbali.co.id/wp-content/plugins/formcraft/file-upload/server/content/files/16079fa9ec30ea---33415241944.pdf
    • https://readxyz.org/wp-content/plugins/super-forms/uploads/php/files/3010051ad6d1dca35ad6d2144025b061/98499582099.pdf
    • http://st-communications.com/ckfinder/userfiles/files/kuzajuweviwama.pdf
    • http://www.consorcio.edu.pe/wp-content/plugins/formcraft/file-upload/server/content/files/16073d9c13d526---35944242825.pdf
    • https://actorconseil.com/files/file/lebenijedivotul.pdf
    • https://www.qlsny.com/wp-content/plugins/super-forms/uploads/php/files/dccbcc7af5c59581abe07759e9529094/80147456757.pdf
    • http://www.investing-in-women.com/wp-content/plugins/formcraft/file-upload/server/content/files/160b1f39cabfe9---mejedif.pdf
    • http://viviapalermo.com/userfiles/files/91634180308.pdf
    • https://regalcabs.co.uk/wp-content/plugins/formcraft/file-upload/server/content/files/160755e8fa940f---54100966361.pdf
    • http://w-f-l.de/user_img/file/wuxiserijikinopazebufuse.pdf
    • http://asesorialuishervas.com/wp-content/plugins/formcraft/file-upload/server/content/files/16074b56a9a5f8---62832121433.pdf
    • http://www.miamiairportlimo.net/wp-content/plugins/formcraft/file-upload/server/content/files/1607222b51dea6---28638452971.pdf
    • http://ei-windykacja.pl/upload/file/lerirewadamafamaviwoke.pdf
    • http://www.dadosefatos.net.br/wp-content/plugins/formcraft/file-upload/server/content/files/160ad82ed279a7---nuzevokujajogidaxinino.pdf
    • https://sieuthimaytinhcu.vn/upload/files/69995959988.pdf
    • https://viboot.com/ckfinder/userfiles/files/sowitorabojiwujebugap.pdf
    • http://insureacompany.com/userfiles/file/58864026697.pdf
    • https://phase1acoustics.com/wp-content/plugins/formcraft/file-upload/server/content/files/160a638119c474---33453432073.pdf
    • http://ck-kutnahora.cz/gais/image/file/xulimob.pdf
    • http://www.highlandmetals.co.za/wp-content/plugins/formcraft/file-upload/server/content/files/16099ed5c783dc---zelijatova.pdf
    • http://www.asejnrtigers.co.uk/wp-content/plugins/formcraft/file-upload/server/content/files/160a5ec6d66a70---nisekavaxarizovixetaxen.pdf
    • http://ruishikaishi.com/upload/content/files/2021/06/20210611145958.pdf
    • http://vds-construct.pl/userfiles/file/75173622471.pdf
    • https://denizlihorozu.com/resimler/files/kakifinekane.pdf
    • https://feedproxy.google.com/~r/Uplcv/~3/YTWXjIUwRh0/uplcv?utm_term=medical+term+for+two+different+colored+eyes
    • 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_off000111cd.bin
b6be974f03ceed9893b13a4c5d5111ef62e40dedb68db775029939d1b2c1e0a7
pdf-font-stream PDF embedded font (sfnt) at offset 0x111CD 20228 bytes
font_01_sfnt_off000144f5.bin
9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
pdf-font-stream PDF embedded font (sfnt) at offset 0x144F5 16792 bytes
font_02_sfnt_off00015d0c.bin
016212d2c5e4a348fd98986030d8d271f1a482a1561cf6c97a43f9d40e289cd5
pdf-font-stream PDF embedded font (sfnt) at offset 0x15D0C 10832 bytes