Malicious PDF — malware analysis report

Static analysis result for SHA-256 cd1159897b54257c…

MALICIOUS

PDF

71.5 KB Created: 2021-06-09 14:45:49 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 4.8.7)
MD5: bdf56c0a1088c5c1f27455c4fb0a0f95 SHA-1: 1755b7fb7fac3b5383c559c6714de7735f420b0c SHA-256: cd1159897b54257c3047864068a736a2684a7b853a576bb5c2804ed0e36f024b
164 Risk Score

Malware Insights

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

This PDF file was flagged by a machine learning classifier and ClamAV as malicious, indicating a high likelihood of malicious intent. The heuristics reveal it functions as a link farm, directing users to compromised WordPress upload storage and other disposable hosting sites, likely to facilitate the download of a secondary payload. The presence of a 'download button' lure further supports a phishing or social engineering attack pattern.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9998

Heuristics 7

  • 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.
  • Visual download / call-to-action button lure low SE_DOWNLOAD_BUTTON
    Document contains a call-to-action phrase ('Click here to download', 'Download Now', etc.) — low-signal unless other findings point to a malicious workflow
  • 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://laborke.ru/uplcv?utm_term=attached+book+free+download
    • https://cananalimdar.com/wp-content/plugins/super-forms/uploads/php/files/tqud770qa95m65429aah2k548u/37795091306.pdf
    • https://profbuhotchet.ru/wp-content/plugins/super-forms/uploads/php/files/5b502064ad25faa5e41cd542ab98b957/govobivo.pdf
    • https://www.americansummercamps.com/wp-content/plugins/formcraft/file-upload/server/content/files/16087936e28ce1---wusonelipulituwusi.pdf
    • https://www.servicioscalibrados.com/wp-content/plugins/super-forms/uploads/php/files/a2e881609ac72dc81685a2a8f8590533/zuvuzexalamajulidanubil.pdf
    • http://www.adarshvidhyasankul.org/userfilesfile/vitevujulibaluwejexasasi.pdf
    • http://scheiden-maassluis.nl/uploads//file/megomuxafilezeweke.pdf
    • http://www.sunargrup.com.tr/wp-content/plugins/super-forms/uploads/php/files/gt5nnfvl970hug59lgs2vg62a4/koxipodebuwi.pdf
    • https://messianic.live/wp-content/plugins/super-forms/uploads/php/files/4c6974c3d1ded8a1d941eec2a691db0d/bozojorusoxajedemuruzal.pdf
    • http://www.acefence.com/wp-content/plugins/formcraft/file-upload/server/content/files/1609bb443955e9---36274388277.pdf
    • http://zonazero.es/userfiles/file/pitetewisumimedekogalido.pdf
    • http://totalfinance.ca/wp-content/plugins/formcraft/file-upload/server/content/files/160a53b7628673---36358784120.pdf
    • https://dbjadow.pl/attachments/file/17387213889.pdf
    • https://ketgate.eu/wp-content/plugins/super-forms/uploads/php/files/860116e8c682bdb88ddcd4b9ff0cd927/fifukagofa.pdf
    • https://isleo.com/i_photos/file/56726739947.pdf
    • https://qualitylightsolutions.com/wp-content/plugins/super-forms/uploads/php/files/c9ad981dffa3b842f6f237e6bb25c285/duzisutefiledowovabegob.pdf
    • https://123kozijnofferte.nl/wp-content/plugins/super-forms/uploads/php/files/qp56sj6jtnn6dsboeti520ho02/zurazefabofalugu.pdf
    • https://senzedigicraft.com/wp-content/plugins/super-forms/uploads/php/files/62e7a227640399d0e04e75d1e95e0dc0/mijugul.pdf
    • http://arniestribu.com/campannas/file/42107880396.pdf
    • https://blackknowledge.com/wp-content/plugins/super-forms/uploads/php/files/e30e8e0098e6e1d3d0cb2584b9ac51c4/newivadegilitiwe.pdf
    • http://www.ascendercorp.com/
    • http://www.ascendercorp.com/typedesigners.html
    • 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_off0000db57.bin
84282d18cfe9b4b97e62e5676554943f9b5e3361ccc72a72ff618ba3a6fcd2ab
pdf-font-stream PDF embedded font (sfnt) at offset 0xDB57 5216 bytes
font_01_sfnt_off0000ed20.bin
fe4108b6b9cf048d274720b72582dec90837361666ee71a1bdd93683ae851941
pdf-font-stream PDF embedded font (sfnt) at offset 0xED20 10452 bytes