Malicious PDF — malware analysis report

Static analysis result for SHA-256 4123251c943c5535…

MALICIOUS

PDF

70.8 KB Created: 2021-04-30 10:13:40 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 4.8.7)
MD5: 2c58b061a9403be8aeab271e3f9512f3 SHA-1: 58efc5068eacb98e80b7f9a77124bcd62878a9b2 SHA-256: 4123251c943c553573d0a51ff82427b6588e94206bc984b5bbd6515a4354c873
156 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment

The PDF contains numerous links pointing to compromised WordPress sites, a common tactic for hosting malicious content or redirecting users to phishing pages. The ML classifier and ClamAV detection strongly indicate malicious intent. The presence of multiple distinct hosts and a link farm structure suggests an attempt to distribute malicious content across various compromised platforms.

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 https://www.a2zmedical.com.au/wp-content/plugins/formcraft/file-upload/server/content/files/16081a3da79f70---59927720779.pdf
    • http://admio.ru/wp-content/plugins/formcraft/file-upload/server/content/files/16084e8d8b9427---wevetajokomubupe.pdf
    • https://www.pharmaright.ca/wp-content/plugins/super-forms/uploads/php/files/oe3uo076jaqu4o0je81sis53re/74129723722.pdf
    • http://www.vivelamusica.es/wp-content/plugins/formcraft/file-upload/server/content/files/1607b5fd630e78---87228039201.pdf
    • http://www.radioemka.com/wp-content/plugins/formcraft/file-upload/server/content/files/16071bef3b0550---bamasagakanowagobutus.pdf
    • http://modelkyujin.com/wp-content/plugins/formcraft/file-upload/server/content/files/16084c3d946e59---gemagixowodolopukudalelil.pdf
    • https://stellabakingcompany.com/wp-content/plugins/formcraft/file-upload/server/content/files/1606d2805b11e5---2274190784.pdf
    • http://gostium.com/wp-content/plugins/formcraft/file-upload/server/content/files/1606c91df10988---6056827107.pdf
    • http://www.onegelha.com/wp-content/plugins/super-forms/uploads/php/files/6d0956966d14edc3e66953f170f39f66/keserasemijigoken.pdf
    • https://nam.it/wp-content/plugins/formcraft/file-upload/server/content/files/160813fb5497e1---93005339215.pdf
    • https://glass-haus.ru/wp-content/plugins/super-forms/uploads/php/files/8df5074c7d314ad76db6ce0a96cd2230/jemewewuvivefogeba.pdf
    • http://www.grupohk.com.br/wp-content/plugins/formcraft/file-upload/server/content/files/1607199db20e0d---20381583386.pdf
    • http://www.morenoroofing.com/wp-content/plugins/formcraft/file-upload/server/content/files/160738b475f57a---99087925844.pdf
    • http://oneself.pro/wp-content/plugins/formcraft/file-upload/server/content/files/1607707fc33eca---7861017463.pdf
    • https://kodeac.com/wp-content/plugins/super-forms/uploads/php/files/com7mbl8432kdd4onlbu98krvn/44831541609.pdf
    • https://www.ergunaygoren.com/wp-content/plugins/formcraft/file-upload/server/content/files/1606d21d4b5f09---bivejebulu.pdf
    • http://dossalas.com/wp-content/plugins/super-forms/uploads/php/files/7050a27caac46107966bba15e2fddf07/sulaxitaru.pdf
    • http://www.combatsim.eu/wp-content/plugins/formcraft/file-upload/server/content/files/16073c464a1151---94909823096.pdf
    • http://www.ascendercorp.com/
    • http://www.ascendercorp.com/typedesigners.html
    • https://feedproxy.google.com/~r/skout/mBVl/~3/6naE_Nh8_CY/uplcv?utm_term=chain+rule+worksheet+ap+calculus
    • 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://scripts.sil.org/OFL

Extracted artifacts 2

Files carved from inside the sample during analysis.

FilenameKindSourceSize
font_00_sfnt_off0000d767.bin
434d747c33c148c89a4a752ebf3c5fb16484bdfb71ad877d41879caa44cbc865
pdf-font-stream PDF embedded font (sfnt) at offset 0xD767 5084 bytes
font_01_sfnt_off0000e8b6.bin
7e84a03136273036445a00f2ec814ac4f27a4af3f2fac7cc4235e6e8c207b228
pdf-font-stream PDF embedded font (sfnt) at offset 0xE8B6 11000 bytes