Malicious PDF — malware analysis report

Static analysis result for SHA-256 c7182b1a53251461…

MALICIOUS

PDF

85.1 KB Created: 2021-09-18 01:51:30 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-10-24
MD5: 854427b32e70af8b5c6f6d35c824fea4 SHA-1: 7395b5e96a1d3107b9df38b1debc6c6c45b1f84b SHA-256: c7182b1a5325146102cd3edd78cbfb799cde87018f5625404497c7dad7c38cb2
156 Risk Score

Malware Insights

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

The PDF contains numerous embedded URLs, many of which point to compromised CMS upload storage or disposable hosting, indicating a link farm designed to redirect users. The ML classifier and ClamAV detection strongly suggest malicious intent, likely for phishing or distributing further malware. The sample's structure and URL patterns are consistent with a malicious link distribution scheme.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9951

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://wiskind.com/filespath/files/20210911094340.pdf In PDF document text
    • http://slovbau.sk/test/userfiles/file/sufiwibufotigu.pdfIn PDF document text
    • https://eltonltd.ru/sites/default/files/uploads/47982679401.pdfIn PDF document text
    • https://btsis.com/upload/ckfinder/files/43803944019.pdfIn PDF document text
    • https://luatsuavina.com/userfiles/file/73625177574.pdfIn PDF document text
    • http://randoquad72.fr/userfiles/file/71679974723.pdfIn PDF document text
    • http://pol2-simf.ru/userfiles/file/lalesufadijimavexi.pdfIn PDF document text
    • http://xn----9sbbnbtte4cyg.xn--p1ai/ckfinder/userfiles/files/vumubipeti.pdfIn PDF document text
    • https://deewo.de/wp-content/plugins/formcraft/file-upload/server/content/files/1613ff7acd76ea---96761597507.pdfIn PDF document text
    • http://rioairporttransfer.com/ckfinder/userfiles/files/95591950872.pdfIn PDF document text
    • https://xn--i1aam8cb.xn--p1ai/wp-content/plugins/super-forms/uploads/php/files/8911f297a1b3cc5839e53415401b8e34/mesuzelexegulemokizadu.pdfIn PDF document text
    • https://kayakbranson.com/wp-content/plugins/formcraft/file-upload/server/content/files/161351aa1622d9---1414026199.pdfIn PDF document text
    • https://bitree.ru/ckfinder/userfiles/files/fipafeworakodemavu.pdfIn PDF document text
    • https://firesystem.ro/imagini_ws/kodowekagapi.pdfIn PDF document text
    • https://www.sesc.com.ua/wp-content/plugins/super-forms/uploads/php/files/5du7m2tu8r62kulvonp1u6ev73/23027381659.pdfIn PDF document text
    • https://smg.bid/ckfinder_userfiles/files/24409016167.pdfIn PDF document text
    • http://cauthangdep24h.com/upload/files/34093163060.pdfIn PDF document text
    • http://jcbcharpentebois.com/ressource/site-image/files/pinebosevuwetibalilemedi.pdfIn PDF document text
    • http://ednak.com/wp-content/plugins/formcraft/file-upload/server/content/files/16141ebcb60225---pozakazejusutufodaseja.pdfIn PDF document text
    • http://concilianavarra.com/userfiles/files/86453805067.pdfIn PDF document text
    • https://transmar.biz/ckfinder/userfiles/files/37935317588.pdfIn PDF document text
    • https://pointvirgule.ca/upload/editor/file/50512727336.pdfIn PDF document text
    • http://librojuridico.com/aym_images/files/mumamanawopevelimag.pdfIn PDF document text
    • http://happinessgown.com/upload/users/files/lipegozapufabenorukaro.pdfIn PDF document text
    • https://feedproxy.google.com/~r/1eyvgo/aqOO/~3/3CAf4wW3hvY/uplcv?utm_term=redmi+note+9+5g+bdPDF 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_off0000de73.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xDE73 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
font_01_sfnt_off0000f68a.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xF68A 10604 bytes
SHA-256: 8d5cced95bfbfb88498126a00f9ae4c8329c04812c6900962ebd99000019b77c
font_02_sfnt_off00010e8e.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x10E8E 21516 bytes
SHA-256: a9b56cc90104cf873a0f74ea38bfb5742e105a28459ebc56a0d6806e2a8788cb