Malicious PDF — malware analysis report

Static analysis result for SHA-256 eb85b936533765b1…

MALICIOUS

PDF

71.0 KB Created: 2021-06-06 13:07:11 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 4.8.7)
MD5: 9a945a52d632c107531a3ebad63acbf1 SHA-1: f93a6c31e48f203cd566cfa71e2a4b687b5a1617 SHA-256: eb85b936533765b1d7f00622bd601279cf4d9ef065c61232633c2f84affe5e51
156 Risk Score

Malware Insights

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

The PDF document contains numerous embedded URLs, many of which point to compromised WordPress sites or disposable hosting, suggesting a link farm designed to redirect users to malicious content. The ClamAV detection and ML classifier strongly indicate malicious intent, likely phishing or malware distribution. No scripts were extracted, but the heuristic firings and URL analysis are sufficient to assess the attack pattern.

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 https://synerhu.ru/uplcv?utm_term=dingbats+game+answers+level+138
    • https://www.qbuildsoftware.com/wp-content/plugins/super-forms/uploads/php/files/57898a1b9bd970a711df128f7ee52b86/tisilakezojitesulebib.pdf
    • http://asesoriagarpe.com/wp-content/plugins/formcraft/file-upload/server/content/files/1607c87314b123---bevefopepewonozu.pdf
    • http://jockmurray.com/wp-content/plugins/formcraft/file-upload/server/content/files/1608ee93f8fa3c---20845128452.pdf
    • https://ethiquedevelopers.com/wp-content/plugins/super-forms/uploads/php/files/966a569ba7350d6ac533ecb28d7ba1ad/juvikakipaguzidoziwo.pdf
    • http://www.megasaludips.com/wp-content/plugins/formcraft/file-upload/server/content/files/160bb078ae25e3---pexadewobala.pdf
    • http://www.northeastmarquees.com/wp-content/plugins/super-forms/uploads/php/files/2f01aab6f6e855443414cf39c900daeb/gefuwedodakikawusetavor.pdf
    • https://www.skyline-recruiting.com/wp-content/plugins/super-forms/uploads/php/files/4c50a7994e2d40b5bc2cc2426bb59a0c/94638526599.pdf
    • http://sh8ke.com/wp-content/plugins/formcraft/file-upload/server/content/files/1607989da445bb---biwexebotulija.pdf
    • http://msci.com.ng/wp-content/plugins/formcraft/file-upload/server/content/files/160943e23a6b2b---4332288474.pdf
    • https://holzhaus-suedtirol.it/wp-content/plugins/formcraft/file-upload/server/content/files/1607c17b9a8e3d---romogorefo.pdf
    • https://singaporenotarypublic.com/wp-content/plugins/super-forms/uploads/php/files/409be21e5360f66427283ef1887dcc30/11298887737.pdf
    • http://theydeserveastamp.org/wp-content/plugins/formcraft/file-upload/server/content/files/16087b350895e9---83241364212.pdf
    • https://www.histoiresdegroupes.com/wp-content/plugins/formcraft/file-upload/server/content/files/1607e7975c2005---93212531350.pdf
    • http://www.fotografoeventimilano.com/wp-content/plugins/formcraft/file-upload/server/content/files/160b8e5404e62f---80687591614.pdf
    • http://www.scsi.coop/wp-content/plugins/super-forms/uploads/php/files/87f7147fc0c328e7bb1f1862d43cf27d/zikenuvajiz.pdf
    • https://refour.dk/wp-content/plugins/super-forms/uploads/php/files/2eb89b66331ca1e587187bd219dd2f71/wezedi.pdf
    • http://www.1000ena.com/wp-content/plugins/formcraft/file-upload/server/content/files/1607c9722c0dcd---xadulixojerijiluma.pdf
    • http://www.ascendercorp.com/
    • http://www.ascendercorp.com/typedesigners.html
    • http://www.daltonmaag.com/
    • http://www.w3.org/1999/02/22-rdf-syntax-ns#
    • http://purl.org/dc/elements/1.1/
    • http://ns.adobe.com/pdf/1.3/
    • http://ns.adobe.com/xap/1.0/
    • http://ns.adobe.com/xap/1.0/mm/
    • http://ns.adobe.com/xap/1.0/rights/
    • http://scripts.sil.org/OFL

Extracted artifacts 3

Files carved from inside the sample during analysis.

FilenameKindSourceSize
font_00_sfnt_off0000cb6b.bin
d06a469818552ce47ce71f2f8da329269dbd028ca741c304ed7c24f85a35c806
pdf-font-stream PDF embedded font (sfnt) at offset 0xCB6B 5384 bytes
font_01_sfnt_off0000ddb0.bin
c5a0eaf64b48f15f9cc7e644300131b5aefcc57d26feef6bd1c7d64cb2397a49
pdf-font-stream PDF embedded font (sfnt) at offset 0xDDB0 9808 bytes
font_02_sfnt_off0000ff31.bin
a542ec26cea93e049a2e27cd59b1347dd9bbdea13775fd7b822b3c2b3136116f
pdf-font-stream PDF embedded font (sfnt) at offset 0xFF31 4324 bytes