Malicious PDF — malware analysis report

Static analysis result for SHA-256 1882ab12698b198a…

MALICIOUS

PDF

101.9 KB Created: 2021-08-09 05:37:51 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-11-24
MD5: 107cbb40303df6000b7b0260575a26aa SHA-1: fd7c34673b1751d030225ab6b5292cdc5fc98aaf SHA-256: 1882ab12698b198a2b271eac39ab9548772286e43950c5357b140a84fd17e667
156 Risk Score

Malware Insights

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

The PDF contains a large number of external links, many of which point to compromised or disposable domains, indicating a link farm designed to distribute malicious content or phish users. The ML classifier and ClamAV detection strongly support its malicious nature. The document body is heavily obfuscated and appears to be non-readable content generated by wkhtmltopdf, providing no direct clues about the lure.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9986

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 http://kaitosushisb.com/uploads/files/28285055697.pdf In PDF document text
    • https://rachelrom.com/rescontent/file/67027888306.pdfIn PDF document text
    • http://anhuifan.com/upload_fck/file/2021-6-25/20210625182744745564.pdfIn PDF document text
    • http://nuyewpilot.academy/wp-content/plugins/super-forms/uploads/php/files/f8b83cf53bbaab93837014f950f867fd/lisoge.pdfIn PDF document text
    • http://dmhu.eu/uploads/uplib/file/16487313000.pdfIn PDF document text
    • https://kham.vn/userfiles/file/kodofipipobeliz.pdfIn PDF document text
    • https://www.dekleinewerf.nl/wp-content/plugins/formcraft/file-upload/server/content/files/160a864497c5f4---fivuwuvokuzebolaje.pdfIn PDF document text
    • http://ttccid.com/userfiles/file/kenepunarulukirurupoviva.pdfIn PDF document text
    • http://alarcon-v.com/editor_upload_image/file/15933998013.pdfIn PDF document text
    • https://cpsguffanti.com/uploads/file/91743214958.pdfIn PDF document text
    • http://montpellier-businessplan.com/mbp/upload/images/images/upload/ckfinder/99410349093.pdfIn PDF document text
    • https://universal4shipping.net/userfiles/file/xibowe.pdfIn PDF document text
    • https://sce.tw/uploads/files/60fa09adc3ca4.pdfIn PDF document text
    • https://rhythmcprandfirstaid.com/wp-content/plugins/super-forms/uploads/php/files/826741325cb56f42510ae2faa1d37ff2/jizulinepepovi.pdfIn PDF document text
    • https://esteticarcare.com/wp-content/plugins/super-forms/uploads/php/files/6bb4d320e8b593e103c43d463ec39d4b/69873570293.pdfIn PDF document text
    • http://train-in-japan.com/images/blog//file/39631881029.pdfIn PDF document text
    • http://davidhammerstein.org/userfiles/file/42819781284.pdfIn PDF document text
    • https://www.officinadelgustoroma.com/wp-content/plugins/super-forms/uploads/php/files/7e738cce1eb7968855949510614f30db/76406597565.pdfIn PDF document text
    • http://www.fsnn.se/wp-content/plugins/formcraft/file-upload/server/content/files/160787025bb489---pasoji.pdfIn PDF document text
    • http://brighterhealthcare.co.uk/wp-content/plugins/super-forms/uploads/php/files/d7n15p6b0j4fa8d1a7p8npbb1p/menufudujudigov.pdfIn PDF document text
    • http://saamfactory.com/wp-content/plugins/super-forms/uploads/php/files/d9dfd7498d96526f9f51a75e40471cb4/8685865975.pdfIn PDF document text
    • http://parkwestresidences.com/wp-content/plugins/formcraft/file-upload/server/content/files/16085ec37cb15b---12126905243.pdfIn PDF document text
    • https://www.khaosanpools.org/ckfinder/userfiles/files/juzorunikaxaxabiwuzosa.pdfIn PDF document text
    • https://feedproxy.google.com/~r/1eyvgo/aqOO/~3/S30rS-6n6vg/uplcv?utm_term=kendall+manual+muscle+testing+book+pdf+downloadPDF 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_off0001294e.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x1294E 17352 bytes
SHA-256: 232a07a4d4185ced44dcd95fd8a5a1646d77d7c116ebea5bcc2dcac6f39f86de
font_01_sfnt_off000156f7.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x156F7 11272 bytes
SHA-256: 8a5ecf4fcb4b4581d7ab968cb9d2625cafa682ff200d6e544dca4a66177877c7
font_02_sfnt_off00017115.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x17115 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1