Malicious PDF — malware analysis report

Static analysis result for SHA-256 729efa9bce0883a4…

MALICIOUS

PDF

78.5 KB Created: 2021-08-19 00:22:34 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-09-29
MD5: 5f17025bb93f1351f7f5f4ab6cd82f12 SHA-1: 1e06fff29cf3edc3a7adad6711b1931a9525812c SHA-256: 729efa9bce0883a446e95475a15d36bd6fb985203ef63c01a46f3c37ba270ab8
156 Risk Score

Malware Insights

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

The PDF contains numerous links, many of which point to compromised CMS upload directories, indicating a link farm designed to distribute malicious content. The ML classifier and ClamAV detection strongly suggest malicious intent, likely related to phishing or malware distribution via these links.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9988

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://holzhaus-suedtirol.it/wp-content/plugins/formcraft/file-upload/server/content/files/160c8c28456bce---josud.pdf In PDF document text
    • http://amtusa.com/wp-content/plugins/formcraft/file-upload/server/content/files/160d75c720e0cd---51248330235.pdfIn PDF document text
    • http://okna-stv.ru/userfiles/files/37629740934.pdfIn PDF document text
    • http://indigobaby.eu/upload/files/47460592792.pdfIn PDF document text
    • https://ohligschlaeger-berger.de/wp-content/plugins/formcraft/file-upload/server/content/files/160cd623ad5c91---32318300284.pdfIn PDF document text
    • http://for-rent-aalst.com/wp-content/plugins/formcraft/file-upload/server/content/files/160c252b685b44---dajovasimusixafiwutita.pdfIn PDF document text
    • https://allianceflooring.net/wp-content/plugins/super-forms/uploads/php/files/280d43fe92c5a1392d9013847e5383df/50517353038.pdfIn PDF document text
    • https://baconbites.com/wp-content/plugins/super-forms/uploads/php/files/8aeletd5ebuu48ucouc4mg6667/dakivuwejeb.pdfIn PDF document text
    • http://makaeximworld.com/wp-content/plugins/formcraft/file-upload/server/content/files/160b0d38c7ec35---6683450294.pdfIn PDF document text
    • https://twinslock.com/ckfinder/userfiles/files/24850446384.pdfIn PDF document text
    • http://www.saraviation.com/wp-content/plugins/formcraft/file-upload/server/content/files/160afe2d4f16b4---14743730278.pdfIn PDF document text
    • http://pumarecovery.com/userfiles/files/63115915557.pdfIn PDF document text
    • https://chamsocmuihong.com/wp-content/plugins/super-forms/uploads/php/files/d4asjniafd17f1s6p0sv1vgfoj/40667478851.pdfIn PDF document text
    • https://marcuspietrek.de/MARCUS/files/file/zejebusizizevosifevotov.pdfIn PDF document text
    • http://misosmile.com/upload/editor/files/nedijudogodef.pdfIn PDF document text
    • http://agendaalzheimer.org/files/galeria/files/dipinaramevivutoxew.pdfIn PDF document text
    • http://vizugy.hu/uploads/files/kofozazegukozatavapu.pdfIn PDF document text
    • http://furkansigorta.com.tr/wp-content/plugins/formcraft/file-upload/server/content/files/1608cee3fe8cce---vulonulafatosixux.pdfIn PDF document text
    • http://adacu.org/userfiles/file/20210614195129.pdfIn PDF document text
    • http://agro-vostok.ru/userfiles/file/4437618401.pdfIn PDF document text
    • https://majubesar.info/contents//files/32524345555.pdfIn PDF document text
    • https://armagedonspedycja.pl/files/file/maweziziwe.pdfIn PDF document text
    • https://adm.allianceflooring.net/wp-content/plugins/super-forms/uploads/php/files/fff3d9848059541a03dbc2514b2b1324/wadowa.pdfIn PDF document text
    • https://feedproxy.google.com/~r/skout/mBVl/~3/GLLx1DTH0VQ/uplcv?utm_term=lesson+8.1+similar+shapes+and+scale+drawings+worksheet+answersPDF 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_off0000cba6.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xCBA6 17112 bytes
SHA-256: 41952652ce35ef9b5115ada99848f49b68afc052905b20d9b04ccb996fdcbd32
font_01_sfnt_off0000f823.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xF823 11420 bytes
SHA-256: 45f4c1f2892b6f98f7c0c0a379b03906645516b80f32118839fe5724dbaa2703
font_02_sfnt_off000112cf.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x112CF 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1