Malicious PDF — malware analysis report

Static analysis result for SHA-256 cd362a823937eb6c…

MALICIOUS

PDF

90.1 KB Created: 2021-09-13 16:30:04 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-10-26
MD5: 23549451e99956d89a638a346896c252 SHA-1: 1d6585bbe94fb98c3a83d2975de925af72c7c9d7 SHA-256: cd362a823937eb6c30783ab5320792d4c6c5871b6a1f85b9b17c3b925ac16323
156 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment

The PDF file contains a link farm pointing to numerous unknown PDF files hosted on compromised or disposable domains, as indicated by the 'PDF_SEO_DISPOSABLE_LINK_FARM' and 'PDF_COMPROMISED_CMS_UPLOAD_LINK_FARM' heuristics. The ML classifier and ClamAV detection strongly suggest malicious intent, likely for phishing or distributing further malware. No scripts were extracted, but the structure itself is indicative of a malicious lure.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9948

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 https://auto-rujo.com/images-editor/file/pagiki.pdf In PDF document text
    • https://strongpointmarketing.net/userfiles/file/wisopopaf.pdfIn PDF document text
    • https://nusbetaja2.com/contents/files/89154806598.pdfIn PDF document text
    • http://idevicesplus.nl/app/webroot/files/userfiles/files/29055309026.pdfIn PDF document text
    • http://jtg-antracyt.pl/files/file/23692037211.pdfIn PDF document text
    • https://amezdigital.com/wp-content/plugins/super-forms/uploads/php/files/6eeb44ada3626825d0d7c6c1ea2981bf/37036165113.pdfIn PDF document text
    • http://luckyassessoria.com.br/wp-content/plugins/formcraft/file-upload/server/content/files/1612edd090d8a8---88462319030.pdfIn PDF document text
    • https://pmsp-me.com/userfiles/files/misokojevunubodatugivid.pdfIn PDF document text
    • https://xn--78-6kce7dfhb9dwb.xn--p1ai/wp-content/plugins/super-forms/uploads/php/files/d1e3e133fb556acd2716a686d5acf164/vazonekazuwimufijifopajor.pdfIn PDF document text
    • http://studiopignotti.it/userfiles/files/44150684641.pdfIn PDF document text
    • http://mudrkanuch.sk/editor_uploads/system/files/93911529385.pdfIn PDF document text
    • http://allasclub.com/campannas/file/gegodutusenipi.pdfIn PDF document text
    • https://nhahangthanghuong.com/uploads/files/24446742493.pdfIn PDF document text
    • https://thefertilizerequipment.com/d/files/jevipigataguzorapu.pdfIn PDF document text
    • http://worldprint.su/userfiles/file/71869666345.pdfIn PDF document text
    • https://congtydaihai.com/upload/files/38309698410.pdfIn PDF document text
    • https://zohopin.com/calisma2/files/uploads/vedutolalesevuki.pdfIn PDF document text
    • http://youngthisyear.com/ckfinder/userfiles/files/furafatebuki.pdfIn PDF document text
    • http://manilag.com/FileData/ckfinder/files/20210910_1607D71327DE1F1D.pdfIn PDF document text
    • https://rsvforum.com/userfiles/file/negepin.pdfIn PDF document text
    • http://kfnmsz.com/upfolder/e/files/20210913061118.pdfIn PDF document text
    • https://freebcard.com/ckfinder/userfiles/files/rubilemiperaxikasezubaf.pdfIn PDF document text
    • https://agri-mal.pl/userfiles/file/muwora.pdfIn PDF document text
    • https://feedproxy.google.com/~r/Uplcv/~3/3vuEKuznOb8/uplcv?utm_term=instant+house+mod+minecraft+pePDF 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_off0000f394.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xF394 10892 bytes
SHA-256: 4de31af73057aca445cb5f51376a1f3e9511c928797da626ebda54f1691c68e9
font_01_sfnt_off00010c93.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x10C93 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
font_02_sfnt_off000124a5.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x124A5 21036 bytes
SHA-256: 7c6f22545bd592cb1f80243fa13425c7bd3bcc877a07b3b4ed31d8a127357bd7