Malicious PDF — malware analysis report

Static analysis result for SHA-256 43a1c72ce0aad46c…

MALICIOUS

PDF

67.0 KB Created: 2021-06-21 04:04:22 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 4.8.7) First seen: 2021-10-07
MD5: 2d4395a6952f17a61c6544677e86a0a5 SHA-1: 7844933d11d5cee4cf637f4ec707bb1ac8666ddd SHA-256: 43a1c72ce0aad46c6f619c1e0e49bc832a1b645e78215e6cb86851353c61bb8c
156 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment T1203 Exploitation for Client Execution

The PDF file was flagged by ML classifiers and ClamAV as malicious, specifically as a phishing trojan. Heuristics indicate it functions as a link farm, pointing to numerous compromised WordPress upload directories and disposable hosting sites. The embedded URLs suggest an attempt to redirect users to malicious content, likely for phishing or malware distribution.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9998

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://stevis.cz/files/file/kerokuluvoz.pdf In PDF document text
    • http://freemansphotography.com/wp-content/plugins/formcraft/file-upload/server/content/files/16093f58c92108---nenagodivorojoresuwapire.pdfIn PDF document text
    • http://2440027.ru/upload/file/garapadapoxoxonijerutajo.pdfIn PDF document text
    • http://www.psstrecno.sk/wp-content/plugins/formcraft/file-upload/server/content/files/160773e722144b---45085353058.pdfIn PDF document text
    • https://olmitek.by/wp-content/plugins/super-forms/uploads/php/files/42eetcubm44ad7niqolj1p25v2/zanusakipexevefiromunefaz.pdfIn PDF document text
    • https://ag-concept.ru/wp-content/plugins/super-forms/uploads/php/files/4341fda82156ba16ffb6392035b90c64/xexasubetipawu.pdfIn PDF document text
    • http://www.1000ena.com/wp-content/plugins/formcraft/file-upload/server/content/files/160835cdf820ab---45451323365.pdfIn PDF document text
    • http://www.dadosefatos.net.br/wp-content/plugins/formcraft/file-upload/server/content/files/160809882afbaa---dosawukasup.pdfIn PDF document text
    • http://mobydick-band.de/fckdata/file/banuj.pdfIn PDF document text
    • http://milcontabil.com.br/wp-content/plugins/super-forms/uploads/php/files/0r5v59n4uci6frf741jssviit3/49664718976.pdfIn PDF document text
    • http://www.tenniscanberra.com.au/wp-content/plugins/formcraft/file-upload/server/content/files/160b2b2874441c---xujoxususumevivuwudatub.pdfIn PDF document text
    • http://begemot-rus.com/uploadfiles/file/2021050305360173499.pdfIn PDF document text
    • http://euro520.net/userfiles/file/16208384791694571827.pdfIn PDF document text
    • https://hmv.ir/wp-content/plugins/formcraft/file-upload/server/content/files/1609e5b4bd5c1b---rufadejubipi.pdfIn PDF document text
    • http://alpanelektrik.com/depo/sayfaresim/file/98201030967.pdfIn PDF document text
    • https://watertorens.nl/userfiles/file/viwemixis.pdfIn PDF document text
    • http://www.ascendercorp.com/In PDF document text
    • http://www.ascendercorp.com/typedesigners.htmlIn PDF document text
    • https://feedproxy.google.com/~r/Uplcv/~3/GLLx1DTH0VQ/uplcv?utm_term=draw+a+bear+kindergartenPDF 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://scripts.sil.org/OFLIn PDF document text

Extracted artifacts 2

Files carved from inside the sample during analysis.

FilenameKindSourceSize
font_00_sfnt_off0000c76e.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xC76E 5076 bytes
SHA-256: 529dbd121ca7d37d75afe498f645c9049fa84c166c1709bc07626584b9ebd8de
font_01_sfnt_off0000d8dc.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xD8DC 10792 bytes
SHA-256: ca9fca3008aa4ab8d3529ae44dec9be0dd0abe5a234bc6f1215ca53db908a6d2