Malicious PDF — malware analysis report

Static analysis result for SHA-256 4c9420b226471804…

MALICIOUS

PDF

81.0 KB Created: 2021-06-11 10:26:24 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 4.8.7) First seen: 2021-10-12
MD5: 4b471dead383013e75e756879b780290 SHA-1: 35f7c74adae1e705c023d83960ca0b6341059419 SHA-256: 4c9420b226471804c98b114337bbf1492fc7e9cccc55adde379b50fa28eeca3a
156 Risk Score

Malware Insights

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

This PDF file was flagged by multiple heuristics as malicious, including a critical ClamAV detection and an ML classifier indicating a high probability of maliciousness. It functions as a link farm, containing numerous URLs pointing to compromised WordPress sites, likely intended to lure users to phishing pages or download further malware. The presence of external URIs and compromised CMS upload links strongly suggests a distribution or redirection mechanism.

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://catamma.ru/uplcv?utm_term=video+transitions+for+premiere+pro+cc+free+download PDF link annotation
    • http://gf-location.fr/wp-content/plugins/formcraft/file-upload/server/content/files/1608ca59f324f6---nazirudakixifape.pdfIn PDF document text
    • https://www.nobleorthodontic.com/wp-content/plugins/super-forms/uploads/php/files/e9f366f74bdba8254c32770bf95496f8/wibaluxibitapu.pdfIn PDF document text
    • https://macleanpinesdrivingschool.com.au/wp-content/plugins/super-forms/uploads/php/files/b1276713354b27a1879ec393afd410fe/dakigepune.pdfIn PDF document text
    • http://conelser.hu/fck_uploads/file/68804110003.pdfIn PDF document text
    • http://simonhoirup.dk/userfiles/file/41460226456.pdfIn PDF document text
    • https://eatorhours.org/e-bussiness/fckimages/file/vopiperub.pdfIn PDF document text
    • http://investin-khj.ir/ckfinder/userfiles/files/pesija.pdfIn PDF document text
    • https://www.sharpeningfactory.com/wp-content/plugins/formcraft/file-upload/server/content/files/160717050c6e05---68886345078.pdfIn PDF document text
    • http://barcelonasixtytwo.com/userfiles/file/72826581507.pdfIn PDF document text
    • http://busangh.com/attfile/fckimg/file/%5C/202106027568_899231940.pdfIn PDF document text
    • https://www.vibrationmonitoring.asia/wp-content/plugins/formcraft/file-upload/server/content/files/16098f6426df8f---46842780.pdfIn PDF document text
    • http://www.dnevi-sekretarjev.eu/wp-content/plugins/formcraft/file-upload/server/content/files/1607e8a1616148---64562934742.pdfIn PDF document text
    • https://www.mii.net/wp-content/plugins/super-forms/uploads/php/files/6618d2aaaa667a945409b329f856cf96/xajotidadotilimotonixoral.pdfIn PDF document text
    • https://www.sadcmedia.com/wp-content/plugins/super-forms/uploads/php/files/i0058cnrtgc3lu4tc7pj4kbkof/lufibunapekifisewapokuvo.pdfIn PDF document text
    • http://deurwater.com/wp-content/plugins/formcraft/file-upload/server/content/files/16073d562caaed---84533976186.pdfIn PDF document text
    • https://thedestinbeachhouses.com/wp-content/plugins/super-forms/uploads/php/files/098e2aea780a18fca47f2bf2833761ad/lalisojusefonesuxi.pdfIn PDF document text
    • https://charqueadaboavista.com.br/wp-content/plugins/super-forms/uploads/php/files/a19c2b7342c97cbeeda03beb33ba4550/tebokejofunimexijelusukib.pdfIn PDF document text
    • http://www.ascendercorp.com/In PDF document text
    • http://www.ascendercorp.com/typedesigners.htmlIn PDF document text
    • 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_off0000fd0d.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xFD0D 5360 bytes
SHA-256: c69c7a134de31fbe5ddfd0292e67c3514bc7bed1c2f5b00e8700a1637cf211db
font_01_sfnt_off00010f4a.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x10F4A 11568 bytes
SHA-256: da7196ad6cb042af1238011fa8b80c21b93e8c420e06b16991b1b076edf1bad4