Malicious PDF — malware analysis report

Static analysis result for SHA-256 33d833f19f2b9061…

MALICIOUS

PDF

75.8 KB Created: 2021-09-05 08:23:02 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-10-23
MD5: 00d6dfc374e8a8dfc7d591a28b4d66a5 SHA-1: f740f39c0d462003259e3f50dca9648ff5fc7150 SHA-256: 33d833f19f2b90614a5b0712798aea92a41b7602bd3742bc37f5cfa7241bb724
156 Risk Score

Malware Insights

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

The PDF file was identified as malicious by ML classifiers and ClamAV, indicating a phishing or trojan threat. It functions as a link farm, containing numerous URLs that point to compromised WordPress uploads and other disposable hosting sites, likely to distribute further malicious content. The presence of multiple external URIs and the PDF_SEO_DISPOSABLE_LINK_FARM heuristic strongly suggest this document is part of a campaign to lure users to malicious sites.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9973

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://www.pilartangguh.com/file/ralebewabujodomijoboluxa.pdf In PDF document text
    • http://detikakdeti.ru/img/file/30924805510.pdfIn PDF document text
    • https://www.lokalesichtbarkeit.de/wp-content/plugins/super-forms/uploads/php/files/v3kcbsdv2g2b7lrbkrgm1sm96q/47816397400.pdfIn PDF document text
    • https://wurstfargo.com/wp-content/plugins/super-forms/uploads/php/files/40720bc21f69ff9779993351c7e97699/93781452269.pdfIn PDF document text
    • http://naucseto.cz/storage/4364510282.pdfIn PDF document text
    • http://urbanconstructions.org/images/uploadedimages/file/fipefixedirobip.pdfIn PDF document text
    • https://www.blackandwhite-salon.com/wp-content/plugins/super-forms/uploads/php/files/dec5112a4f80e0a3cdb1864618c732b8/91487192353.pdfIn PDF document text
    • http://e-hematologica.pl/users//file/waxakijaxum.pdfIn PDF document text
    • https://aldea.work/wp-content/plugins/super-forms/uploads/php/files/5779999dd7a153868f54f596d9a3fd49/vogonodagasixob.pdfIn PDF document text
    • http://fitnessklub-impuls.pl/uploads/assets/file/81003030541.pdfIn PDF document text
    • https://ahi.com.ua/wp-content/plugins/super-forms/uploads/php/files/ebf10c2be4cbe5dec44a725bb842b9ba/11360976392.pdfIn PDF document text
    • http://kazenergy.kz/wp-content/plugins/formcraft/file-upload/server/content/files/1609eb942a5328---lotepo.pdfIn PDF document text
    • https://lerong.vn/wp-content/plugins/super-forms/uploads/php/files/f671038b325a9cebdc5f54b0f19e0ef6/67446435119.pdfIn PDF document text
    • http://seyrimerdin.com/userfiles/file/xafawebufijalonefox.pdfIn PDF document text
    • http://madinaboys.com/easydo%20v2.00/files/uploads/70720959029.pdfIn PDF document text
    • http://xn----7sbjvweekof5d.xn--p1ai/files/files/dukufi.pdfIn PDF document text
    • http://www.tecnotrefg.it/wp-content/plugins/formcraft/file-upload/server/content/files/160e1d9ec09a41---siwosudofetagojud.pdfIn PDF document text
    • http://adhdadvisory.com/wp-content/plugins/formcraft/file-upload/server/content/files/16072dd6ae5909---tuzikufogolazurax.pdfIn PDF document text
    • http://usateatop.com/_upload/files/rijukabewufokononaku.pdfIn PDF document text
    • https://nnkcreations.com/userfiles/file/89880092576.pdfIn PDF document text
    • https://malashealthcare.com/userfiles/files/desalorako.pdfIn PDF document text
    • http://www.juniorcollege.cl/ckfinder/userfiles/files/fanorizedis.pdfIn PDF document text
    • http://www.nanodrywash.com/wp-content/plugins/formcraft/file-upload/server/content/files/16106ff5f563f3---fupoloxapoxolijox.pdfIn PDF document text
    • https://feng-shuiworld.com/userfiles/file/79245919036.pdfIn PDF document text
    • https://feedproxy.google.com/~r/Uplcv/~3/zMnd8XtcwSM/uplcv?utm_term=someone+like+you+adele+piano+sheet+music+pdfPDF 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_off0000c2e1.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xC2E1 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
font_01_sfnt_off0000daf8.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xDAF8 11168 bytes
SHA-256: 316bec1cc84dd2be63acdcab49eed231590fbc6c836eac3c48cfd57d9c2af86e
font_02_sfnt_off0000f4da.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xF4DA 17292 bytes
SHA-256: 0c93b9eca755ab9c5632885a6b76319f9b67dfb5e9d1df0f16ac6948e80c5226