Malicious PDF — malware analysis report

Static analysis result for SHA-256 8bd90f89776195e8…

MALICIOUS

PDF

94.3 KB Created: 2021-08-14 19:00:03 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-10-26
MD5: 56cfda7ba73e77fe1b20584972913dad SHA-1: 53b43d82b3695eac39f64cd1aafab090e21d6351 SHA-256: 8bd90f89776195e8b63e0bf9ea59d38ca20f12c7333858d3a1941cb3a02c9aef
156 Risk Score

Malware Insights

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

The PDF contains a link farm pointing to numerous URLs, many hosted on compromised CMS uploads and disposable domains, indicating a phishing or malware distribution attempt. The ClamAV detection and ML classifier strongly suggest malicious intent. While no scripts were extracted, the structure and URL patterns are consistent with a malicious PDF designed to lure users to external sites.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9980

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 https://mysilo.com/upload/ckfinder/files/73537049289.pdf In PDF document text
    • http://ziepniekkalns.lv/wp-content/plugins/formcraft/file-upload/server/content/files/16092c761f24b6---70272130807.pdfIn PDF document text
    • https://hoffmanowska.pl/wp-content/plugins/formcraft/file-upload/server/content/files/160a2e4c7b4471---vevijufaso.pdfIn PDF document text
    • https://europartner2.pl/uploads/59100223840.pdfIn PDF document text
    • http://thrifty-uy.com/files/others/33094378470.pdfIn PDF document text
    • http://nuyewrecruitment.com/wp-content/plugins/super-forms/uploads/php/files/9034b6314916681c2b06888f410ada52/zemafan.pdfIn PDF document text
    • https://irantruck.ir/data/file/8416101762.pdfIn PDF document text
    • http://hibertek.com/image/files/20210606_105257.pdfIn PDF document text
    • http://champaigncursillo.com/userfiles/file/47897814863.pdfIn PDF document text
    • http://www.ags-sib.ru/ckfinder/userfiles/files/35066758790.pdfIn PDF document text
    • http://dribblebar.pl/userfiles/file/benajuganovujaluwajarase.pdfIn PDF document text
    • http://bajajsports.com/userfiles/file/69075458005.pdfIn PDF document text
    • https://xn--80aaijz0c.xn--p1ai/ckfinder/userfiles/files/ravimuzizojozifanivem.pdfIn PDF document text
    • https://stollerco.com/testingsites/advantage_aviation/assets/media/file/nowikumitewa.pdfIn PDF document text
    • http://beastyenergy.com/userfiles/file/68513979225.pdfIn PDF document text
    • https://www.acptechnologies.com/wp-content/plugins/formcraft/file-upload/server/content/files/160f190511a895---xogowamiluvagolisujujufud.pdfIn PDF document text
    • https://lawina-radom.pl/files/file/2761764191.pdfIn PDF document text
    • http://samurairamenbar.com/uploads/files/jipajotamo.pdfIn PDF document text
    • https://bowenpainter.com/wp-content/plugins/formcraft/file-upload/server/content/files/160ce2398cdd8e---8153058500.pdfIn PDF document text
    • https://www.lamuccacompany.com/wp-content/plugins/super-forms/uploads/php/files/d26f6c2340bd411987bd7d78ca43c549/74166616825.pdfIn PDF document text
    • https://uleshuzataruhaz.hu/files/file/94579144554.pdfIn PDF document text
    • https://www.finestkindcharter.com/wp-content/plugins/formcraft/file-upload/server/content/files/1609297b3a0d9e---83972456669.pdfIn PDF document text
    • https://kakvkusno26.ru/wp-content/plugins/super-forms/uploads/php/files/c484e6a5f01ec5396b94b5273ccf0d25/waneb.pdfIn PDF document text
    • http://www.movingintofreedom.com/wp-content/plugins/formcraft/file-upload/server/content/files/16098e2f5158da---vonedokadusixipakabopajo.pdfIn PDF document text
    • https://saam.vn/images/content/file/37469487124.pdfIn PDF document text
    • https://feedproxy.google.com/~r/skout/mBVl/~3/DOqCt-cVA4I/uplcv?utm_term=what+foods+are+allowed+on+an+alkaline+dietPDF 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_off0000f194.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xF194 10620 bytes
SHA-256: e1951b516f42046c99353d7f4d94ff4cdefc69186751db049cf57f9086766084
font_01_sfnt_off000109dd.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x109DD 18152 bytes
SHA-256: 59b2a17cde76b04543b553f816fa193ca743e46340959a6bf9f6c3e067fea0ef
font_02_sfnt_off00013919.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x13919 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
font_03_sfnt_off0001512a.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x1512A 17240 bytes
SHA-256: 97a7d6b3bd18dd92b19129cef1f1608f6a40740aeba231d9c5cf44caa136fb5d