Malicious PDF — malware analysis report

Static analysis result for SHA-256 a52500bff24703c1…

MALICIOUS

PDF

91.6 KB Created: 2021-07-24 16:07:01 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-09-14
MD5: 8d697edf22043016489fd6ffd6d00e43 SHA-1: 0714057a1c775951de1a74c9d86be54831728373 SHA-256: a52500bff24703c1d567bdee0334f0833ad677b1aa904a8f3b1179914b8b2dd4
184 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment T1204.002 Malicious Link

This PDF file was detected as malicious by ClamAV and a machine learning classifier. It contains a link farm pointing to compromised WordPress uploads and other disposable hosting, suggesting an attempt to host and distribute malicious files. The presence of a visual download button further supports a phishing or social engineering lure.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9923

Heuristics 8

  • ClamAV: Pdf.Phishing.Trojan-d2568dad23a94d95-d2568dad23a94d95-10044375-0 critical CLAMAV_DETECTION
    ClamAV detected this file as malware: Pdf.Phishing.Trojan-d2568dad23a94d95-d2568dad23a94d95-10044375-0
  • Malformed active-content stream length medium PDF_MALFORMED_EXPLOIT_STREAM_LENGTH
    A PDF stream that carries active/exploit-looking content has a declared /Length that does not match the recovered stream body. Malformed stream boundaries and length mismatches are common parser-evasion/supporting evidence around Reader exploit streams.
  • 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://www.edutechusa.com/wp-content/plugins/formcraft/file-upload/server/content/files/160b56f93ce55a---34165418553.pdf In PDF document text
    • http://ikra-ekb.ru/files/fckeditor/file/faderovuvelivuzu.pdfIn PDF document text
    • https://baxsporthorses.nl/userfiles/file/63832558630.pdfIn PDF document text
    • https://www.colegiodesafio.net/home/wp-content/plugins/formcraft/file-upload/server/content/files/1608f1d80e52c5---57425276402.pdfIn PDF document text
    • http://npas.ru/pic/file/zaroba.pdfIn PDF document text
    • http://novichiha.ru/pic/file/19287171627.pdfIn PDF document text
    • http://mountmedpharmacy.co.za/wp-content/plugins/formcraft/file-upload/server/content/files/160a3f8362cd84---60475579087.pdfIn PDF document text
    • https://terravistahometeam.com/wp-content/plugins/super-forms/uploads/php/files/20457a6df7bd83cd87254e2e2804378c/fopaledogeremesivabomij.pdfIn PDF document text
    • https://wipaphun.com/UserFiles/File/48789474698.pdfIn PDF document text
    • https://voicelux.ru/wp-content/plugins/super-forms/uploads/php/files/afd1de541bd22bdc446f338c9bca88b1/38102677621.pdfIn PDF document text
    • https://trichynext.com/wp-content/plugins/super-forms/uploads/php/files/aa9e0b2a44953cd233342b2f9a64c1ba/2620193220.pdfIn PDF document text
    • https://aliencosmicexpo.com/wp-content/plugins/formcraft/file-upload/server/content/files/160984cf34459b---84372900947.pdfIn PDF document text
    • http://barrarioservicos.com.br/wp-content/plugins/formcraft/file-upload/server/content/files/160e2162d2ff92---lizejubevuzijuvugobap.pdfIn PDF document text
    • https://www.rath-catering.de/wp-content/plugins/formcraft/file-upload/server/content/files/1609a07ae63ba6---77932364640.pdfIn PDF document text
    • http://mijneigenlift.nl/wp-content/plugins/formcraft/file-upload/server/content/files/160769ed1ee697---5481508493.pdfIn PDF document text
    • http://steelbo.com/uploads/admins/u0/files/20210531061555.pdfIn PDF document text
    • http://aqbnb.com/uploadfile/file/74546646353.pdfIn PDF document text
    • http://www.sunarpazarlama.com/wp-content/plugins/super-forms/uploads/php/files/88lit813j9n4t64qtg3i9k7qh7/71864588420.pdfIn PDF document text
    • https://catherinehourihan.art/wp-content/plugins/super-forms/uploads/php/files/950745944c5ec56e821a3fcb7572c627/wobexi.pdfIn PDF document text
    • https://gachbinhduong.com/upload/file/74313676490.pdfIn PDF document text
    • http://bradleyhillsapartments.com/demo/uploads/contents/file/sikosazogu.pdfIn PDF document text
    • https://zhbiotech.com/CKEdit/upload/files/15700892267.pdfIn PDF document text
    • https://mayurherbal.com/userfiles/file/50637004021.pdfIn PDF document text
    • https://apoc.com.au/wp-content/plugins/super-forms/uploads/php/files/2ab4e5f963505fa863088b3a6ccd5b9b/rikefazukosokeporo.pdfIn PDF document text
    • https://vmkstroi.ru/wp-content/plugins/super-forms/uploads/php/files/6eba18ce1b36d1867fc41d5162747f2b/18971112626.pdfIn PDF document text
    • https://feedproxy.google.com/~r/skout/mBVl/~3/6naE_Nh8_CY/uplcv?utm_term=what+is+whatsapp+plus+latest+versionPDF 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 4

Files carved from inside the sample during analysis.

FilenameKindSourceSize
font_00_sfnt_off0000ed13.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xED13 17020 bytes
SHA-256: 688e2a8119e289706b75f3ea971625fb0757ceefc0afc913f72306be3fcda5bd
font_01_sfnt_off0001198d.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x1198D 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
font_02_sfnt_off000131a4.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x131A4 10592 bytes
SHA-256: 1ae707f831f4cd041f1b7e5a439230fe7b4d97a0027f890d059e6617cdbc12e0
font_03_sfnt_off000149d1.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x149D1 16376 bytes
SHA-256: 0c133022d1e9883d2ff7035cf84f1fa0be9cfa0d671266bc5a940283bc0f9855