Malicious PDF — malware analysis report

Static analysis result for SHA-256 879969b6ca2d3783…

MALICIOUS

PDF

73.0 KB Created: 2021-06-21 18:23:55 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 4.8.7) First seen: 2021-10-24
MD5: 7637a4555e81a067aa042901f56d14b4 SHA-1: 790fa2ebfd87cb2790a03033c7671b1338f82513 SHA-256: 879969b6ca2d3783a4b206103342afdce813e7c151e5c6eb0eccbfc3136c73b5
156 Risk Score

Malware Insights

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

The PDF file contains a link farm pointing to multiple external URLs, many of which are hosted on compromised websites or disposable domains. The ML classifier and ClamAV detection strongly indicate malicious intent, likely for phishing or malware distribution. The document body, though heavily obfuscated, contains text related to downloading music, which could be a lure.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9998

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://kopdesign.nl/userfiles/file/biwiz.pdf In PDF document text
    • http://dabaizhongxue.com/upload_fck/file/2021-6-20/20210620045429266518.pdfIn PDF document text
    • https://arab-hams.com/Ups/files/12297632850.pdfIn PDF document text
    • http://huucodatlanh.com/userfiles/file/50479628741.pdfIn PDF document text
    • https://completecollegestrategies.com/wp-content/plugins/super-forms/uploads/php/files/3f51db927c046e7dd413d53b547b379d/96311953376.pdfIn PDF document text
    • https://aedwea.com/upload/foto/gipoboxiposalugozamilut.pdfIn PDF document text
    • https://ethiquedevelopers.com/wp-content/plugins/super-forms/uploads/php/files/d13b6c4ae606866b11529b55bb7d833e/pewivibikukedomenupupo.pdfIn PDF document text
    • http://www.zopfitravel.com/wp-content/plugins/formcraft/file-upload/server/content/files/160bbcc2cbce16---4543725658.pdfIn PDF document text
    • http://qhs1978.com/clients/d/dd/dd8db5a278a7ad55a2ada34b8e38ebcc/File/nutewubixizavedagerox.pdfIn PDF document text
    • https://www.kalirich.com/wp-content/plugins/super-forms/uploads/php/files/7ljh6c59f05bu5mca8odums486/60921045339.pdfIn PDF document text
    • https://hotelristorantenovecento.it/wp-content/plugins/super-forms/uploads/php/files/9c716e0922a579bfec21ed71e738e321/10123515531.pdfIn PDF document text
    • https://xlux.vn/wp-content/plugins/super-forms/uploads/php/files/2g48h1rq4c64vvj826qsaolcfb/24518677491.pdfIn PDF document text
    • http://tofuyatogo.com/uploads/files/27603437805.pdfIn PDF document text
    • http://www.meglobalinc.co.za/wp-content/plugins/formcraft/file-upload/server/content/files/160ac79d24efe3---busikidelejanapikedo.pdfIn PDF document text
    • https://www.themeshcowork.com/wp-content/plugins/super-forms/uploads/php/files/15db62fd41be0ac3992314562fa1227a/38160865943.pdfIn PDF document text
    • http://www.ascendercorp.com/In PDF document text
    • http://www.ascendercorp.com/typedesigners.htmlIn PDF document text
    • https://feedproxy.google.com/~r/1eyvgo/aqOO/~3/1KS0DP0cxss/uplcv?utm_term=descargar+discografia+de+jose+alfredo+jimenezPDF 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://scripts.sil.org/OFLIn PDF document text

Extracted artifacts 2

Files carved from inside the sample during analysis.

FilenameKindSourceSize
font_00_sfnt_off0000d9dc.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xD9DC 5464 bytes
SHA-256: c6b0b0fc233e76a2a1f5a1feb2e60645c3e2c3a69125b891f1095aa154e2a2e5
font_01_sfnt_off0000ec76.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xEC76 12652 bytes
SHA-256: 6d489ec6e82b7a8426eb7e89a0230675cad132ebf3bb8e7b8a314c11670ccb3c