Malicious PDF — malware analysis report

Static analysis result for SHA-256 3cdc959f0add58ce…

MALICIOUS

PDF

64.3 KB Created: 2021-06-16 02:57:21 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 4.8.7) First seen: 2021-10-16
MD5: 7f70cf991586dac1af6e487c3b905f49 SHA-1: fbfc0ae19424c9c169d7682f15fa871641dd251b SHA-256: 3cdc959f0add58ce70a5fe385570edf913da4148110bb904f24d6bbf9e46af47
156 Risk Score

Malware Insights

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

The file is a PDF containing numerous links to compromised WordPress sites, identified as a link farm. The ML classifier and ClamAV detection strongly indicate malicious intent, likely phishing or malware distribution. The presence of multiple external URIs and the compromised CMS upload link heuristic suggest the document is designed to redirect users to malicious content hosted on these sites.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9998

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 https://medvor.ru/uplcv?utm_term=chandra+chakori+audio PDF link annotation
    • https://sellerflows.com/wp-content/plugins/super-forms/uploads/php/files/ce77ecf7461f106039a8fc028cdd357e/liwutavepimozinabomezelip.pdfIn PDF document text
    • http://kaufdeinauto.de/wp-content/plugins/formcraft/file-upload/server/content/files/1608fd103b00f7---49215821123.pdfIn PDF document text
    • http://nhandieurangmuoi.com/ckfinder/userfiles/files/22091165810.pdfIn PDF document text
    • http://iideree.org/wp-content/plugins/formcraft/file-upload/server/content/files/1607f48fd33c19---47026888248.pdfIn PDF document text
    • https://wlao.on.ca/wp-content/plugins/super-forms/uploads/php/files/82f26e2245882a8c098c727632c417eb/mobisupelorixe.pdfIn PDF document text
    • http://schouteninterieurwerk.nl/wp-content/plugins/formcraft/file-upload/server/content/files/160ae3d346ad36---pulemuwuwozobufetulemi.pdfIn PDF document text
    • https://eclipsetheaters.com/wp-content/plugins/formcraft/file-upload/server/content/files/16073f544371ff---11137729191.pdfIn PDF document text
    • http://baharemadinah.com/wp-content/plugins/formcraft/file-upload/server/content/files/160b683b72b537---sunekar.pdfIn PDF document text
    • http://massvt.sk/editor_uploads/system/files/vomuxoge.pdfIn PDF document text
    • https://www.accidentinjurylascruces.com/wp-content/plugins/super-forms/uploads/php/files/kub0d88lrc43p9na7cnq1r5ch5/bemetot.pdfIn PDF document text
    • http://itaindustrial.com.br/wp-content/plugins/formcraft/file-upload/server/content/files/16093f993aad6c---28655130791.pdfIn PDF document text
    • https://mzr-avocats.com/buddha/ckfinder/userfiles/files/bafugawojutonevojuvozaf.pdfIn PDF document text
    • http://www.idenet.net/wp-content/plugins/formcraft/file-upload/server/content/files/1606c81d942c13---ravetoni.pdfIn PDF document text
    • https://actorconseil.com/files/file/puvabufaxalamonuson.pdfIn PDF document text
    • https://ijpdua.com/contents//files/35224666784.pdfIn PDF document text
    • http://careerhack.net/wp-content/plugins/formcraft/file-upload/server/content/files/160c0e4f15c938---ruwazalikujux.pdfIn PDF document text
    • http://adamlegal.com/userfiles/file/78036986589.pdfIn PDF document text
    • https://myupfield.link/wp-content/plugins/super-forms/uploads/php/files/uefu9ud9vv08tvcv4gq89t5uej/54085498288.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_off0000c425.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xC425 4784 bytes
SHA-256: b290b41e6c225d53f98573910bcbd284c37cf7913eb3f66f8860faaf5680b644
font_01_sfnt_off0000d45d.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xD45D 9684 bytes
SHA-256: 3f92a0075f50d7affd6789b1e0574b28abb1450b3afc10d428d5ffcf89660bac