Malicious PDF — malware analysis report

Static analysis result for SHA-256 50a6199b9127aca7…

MALICIOUS

PDF

79.5 KB Created: 2021-09-10 13:57:59 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-10-14
MD5: e455797b0485034836eaee46e7f71aea SHA-1: f33541e8770c3aceda7e0b66c984c028e49051f9 SHA-256: 50a6199b9127aca779af123527ff2b9389d9e1e9213b6aaf50cb37a5007207e2
176 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment

The PDF contains numerous external URIs and points to compromised CMS upload storage, 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. No scripts were extracted, but the PDF structure itself facilitates the redirection.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9975

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
  • Clickable URI points to raw IP address medium PDF_URI_IP_LITERAL
    PDF contains a clickable HTTP(S) action whose host is a literal IPv4 address. Legitimate documents normally link to named domains; raw-IP destinations are common in disposable phishing and malware-delivery infrastructure.
  • 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://coretry.ru/uplcv?utm_term=remix+os+android+emulator PDF link annotation
    • http://absolutelyneon.com/userfiles/file/49711948537.pdfIn PDF document text
    • http://recruiters-zone.com/wp-content/plugins/formcraft/file-upload/server/content/files/1613848ad99596---xoburumajonid.pdfIn PDF document text
    • https://nawaasha.org/userfiles/file/13579534653.pdfIn PDF document text
    • http://140.121.161.111/ckfinder/userfiles/files/30789523791.pdfPDF link annotation
    • https://sentinels.ro/userfiles/file/fubirajabamosoweb.pdfIn PDF document text
    • https://kirbas.com/img/uploaded/file/36087132557.pdfIn PDF document text
    • http://akbarestate.com/survey/userfiles/files/19104948242.pdfIn PDF document text
    • http://fruitsad.pl/images/file/98067342700.pdfIn PDF document text
    • http://cuanhuaabshanquoc.vn/files/36223122050.pdfIn PDF document text
    • http://gildiamasterov.ru/userfiles/file/wewiwun.pdfIn PDF document text
    • http://warwick-ems.org/userfiles/file/furabuxonebalutopitim.pdfIn PDF document text
    • https://reifenscho.de/wp-content/plugins/formcraft/file-upload/server/content/files/1613b2aca3deec---jawazarakofosumatapovi.pdfIn PDF document text
    • http://hoangduy.vn/vn/files/wufaba.pdfIn PDF document text
    • https://aznamaste.com/ckfinder/userfiles/files/39861896544.pdfIn PDF document text
    • http://veoguidecostarica.com/ci/userfiles/files/xemazigejumizisilexibugov.pdfIn PDF document text
    • https://linhquan-group.com/upload/ck/files/pixom.pdfIn PDF document text
    • http://travelshops.pl/userfiles/file/57664384489.pdfIn PDF document text
    • http://costanzolegal.com/customer/3/d/9/3d947ad6ce2568d98b832ccf5548371bFile/69549659129.pdfIn PDF document text
    • https://kompaspt1.com/contents/files/22387556752.pdfIn PDF document text
    • http://mu-rrrc.com/userfiles/file/kemimubevopixagaxinabupoj.pdfIn PDF document text
    • http://starinviter.com/ckimagefiles/wujirojedemedinuxekiv.pdfIn PDF document text
    • https://ipekyolumedya.com/resim_galeri/file/65875756128.pdfIn PDF document text
    • http://delve-cr.com/uploads/velimegojuvivavenedomo.pdfIn PDF document text
    • http://www.ashtralmedia.com/wp-content/plugins/formcraft/file-upload/server/content/files/161378c383a484---jovorerozerikopigosoliza.pdfIn PDF document text
    • http://jeanchapleau.com/userfiles/file/mupoxasoduduruwutotovuguj.pdfIn PDF document text
    • 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_off0000d1c7.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xD1C7 17740 bytes
SHA-256: fd9bbde911a4278ad341073f5df80baaaec3eb3b226c15c2cbf7290b79ea8ffb
font_01_sfnt_off0000ffd6.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xFFD6 10656 bytes
SHA-256: 6f9b8f42c7f4023ad4b2b2e624dac5a6090c1a1f85736778253cc8066a5956c9
font_02_sfnt_off0001183f.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x1183F 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1