Malicious PDF — malware analysis report

Static analysis result for SHA-256 da55a50692d0b7ed…

MALICIOUS

PDF

120.1 KB Created: 2021-07-08 01:47:50 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3)
MD5: c6157cd9616919c4e677e423fae228d9 SHA-1: cbe9b6745b9f71d720905ea1d22e97768d1cbd59 SHA-256: da55a50692d0b7ed2d66e3d8b8802d09c8702ca5adc9b9d2307e254bc97e2730
156 Risk Score

Malware Insights

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

The PDF contains numerous links, many pointing to compromised WordPress sites utilizing the formcraft plugin for file uploads. The ML classifier and ClamAV detection strongly indicate malicious intent, likely phishing or malware distribution. The presence of link farms on disposable hosting and compromised CMS uploads suggests an attempt to obscure the final malicious destination.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9955

Heuristics 6

  • ClamAV: Pdf.Phishing.Trojan-d2528dad23a95d95-d2528dad23a95d95-10044376-0 critical CLAMAV_DETECTION
    ClamAV detected this file as malware: Pdf.Phishing.Trojan-d2528dad23a95d95-d2528dad23a95d95-10044376-0
  • 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://serendipityorlando.com/wp-content/plugins/formcraft/file-upload/server/content/files/1608487a21e899---tisegululaz.pdf
    • http://skup-laptopow.com/wp-content/plugins/formcraft/file-upload/server/content/files/160dcbf4263f1b---33070921566.pdf
    • http://best-infosystems.com/userfiles/file/xivujonarul.pdf
    • https://storage-in-motion.com/wp-content/plugins/formcraft/file-upload/server/content/files/16075d08814009---11318479404.pdf
    • https://kakvkusno26.ru/wp-content/plugins/super-forms/uploads/php/files/baa176c73a02d71788fdb2cc8b8d122c/baduf.pdf
    • http://baanpowertrain.com/wp-content/plugins/formcraft/file-upload/server/content/files/160c51f769a6a9---murulimunevetinusene.pdf
    • http://homeopathyhongkong.org/files/detesudatofulediruto.pdf
    • https://northstarexecutivesearch.com/wp-content/plugins/super-forms/uploads/php/files/0283eead2cacbe6e6e3217cbd3428067/xipig.pdf
    • https://gift-edu.ru/wp-content/plugins/super-forms/uploads/php/files/579dc628290d2db778de07d20156ad3c/82066760237.pdf
    • http://kleiberit.ru/files/file/8049887949.pdf
    • http://zrdb-drogbud.pl/Upload/file/24219327778.pdf
    • http://memphiscentral1969.com/clients/865565/File/76554029038.pdf
    • https://phase1acoustics.com/wp-content/plugins/formcraft/file-upload/server/content/files/160c74cf7ac8d9---kogixajalififa.pdf
    • http://drstevealbrecht.com/wp-content/plugins/super-forms/uploads/php/files/52c3355f018617f69747de53ba136eab/79914057311.pdf
    • http://cablexconsulting.com/Upload/file/kudelosokedisu.pdf
    • http://ytlcases.com/userfiles/file/88649480072.pdf
    • http://www.fattyweng.com.sg/wp-content/plugins/formcraft/file-upload/server/content/files/1608e43e67cea0---wimafazefuvamasopebujis.pdf
    • http://drapikowski.pl/uploaded/fck_files/file/bagojekizasosakonazut.pdf
    • http://gostium.com/wp-content/plugins/formcraft/file-upload/server/content/files/1607fe43627151---jibozisigunulevimijevi.pdf
    • https://www.treehousecare.org/wp-content/plugins/formcraft/file-upload/server/content/files/160799616bd6a5---1517952363.pdf
    • http://www.morenoroofing.com/wp-content/plugins/formcraft/file-upload/server/content/files/160b291cc40559---29371389934.pdf
    • http://onishi-kyosendo.jp/archive/93430919764.pdf
    • https://stefandes.com/wp-content/plugins/formcraft/file-upload/server/content/files/16075644c8e0e0---72998424129.pdf
    • https://feedproxy.google.com/~r/skout/mBVl/~3/GLLx1DTH0VQ/uplcv?utm_term=worship+moves+the+heart+of+god
    • 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://dejavu.sourceforge.net
    • http://dejavu.sourceforge.net/wiki/index.php/License

Extracted artifacts 3

Files carved from inside the sample during analysis.

FilenameKindSourceSize
font_00_sfnt_off000172a6.bin
ec7e4ff2ed4eccf6eaddf83c3698d9348428525f1990b429cb79edd2386b3db8
pdf-font-stream PDF embedded font (sfnt) at offset 0x172A6 10852 bytes
font_01_sfnt_off00018b90.bin
d90aa3975f99cf5d0b805f537dac829840f26bc3ea0f010c116c57ec450274aa
pdf-font-stream PDF embedded font (sfnt) at offset 0x18B90 17596 bytes
font_02_sfnt_off0001b957.bin
9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
pdf-font-stream PDF embedded font (sfnt) at offset 0x1B957 16792 bytes