Malicious PDF — malware analysis report

Static analysis result for SHA-256 891cd214daaf260d…

MALICIOUS

PDF

69.9 KB Created: 2021-09-13 04:44:01 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3)
MD5: efddec73f2cd33f953d4af979e7ad65f SHA-1: c1974430d4ffea4bcb0f85718455b7d2e6202de3 SHA-256: 891cd214daaf260da1d97039ababb383f464c1745761cbf280c660592dcb4b98
156 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment

The PDF contains numerous links, many pointing to disposable hosting or compromised CMS uploads, indicating a link farm designed to obscure malicious destinations. The ML classifier and ClamAV detection strongly suggest malicious intent, likely for phishing or malware distribution. Although no scripts were explicitly extracted, the PDF structure and link farm heuristics are indicative of an attack pattern that leverages external resources.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9849

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://groupunsur4.com/contents/files/tumibamu.pdf
    • http://matonaklawfirm.com/customer/3/d/9/3d947ad6ce2568d98b832ccf5548371bFile/tenujopetafibak.pdf
    • http://counterreaction.net/wp-content/plugins/formcraft/file-upload/server/content/files/16130ebdf47c14---batorufuji.pdf
    • http://3dprofi.net/images/uploads/file/livujotoxipeve.pdf
    • http://www.saraviation.com/wp-content/plugins/formcraft/file-upload/server/content/files/1613a4534619a1---42613116154.pdf
    • http://changwontour.kr/FileData/ckfinder/files/20210911_09317E1C3EFDB6A8.pdf
    • http://solis.altrodesign.eu/ckfinder/userfiles/files/42608714885.pdf
    • http://rigdrilling.org/userfiles/file/90567850630.pdf
    • https://stayinbranson.com/ckfinder/triplebuserfiles/file/nuzupugupadubefof.pdf
    • http://saconsultancy.com/userfiles/file/42200410335.pdf
    • http://partner-support.net/user_data/userfiles/files/xuwuzakimisiporuri.pdf
    • http://wrtour.com/FileData/ckfinder/files/20210901_DEDCBDAD7030E5CA.pdf
    • https://pcparts.fr/ckfinder/userfiles/files/96199567235.pdf
    • https://srmhomes.com/images/bulk_images/files/97101093826.pdf
    • https://panoramabyty.cz/content/17017832987.pdf
    • http://tuzoltosagmihald.hu/userfiles/file/datenujomibagasiwanerij.pdf
    • http://www.bestlifepolicy.co.uk/wp-content/plugins/formcraft/file-upload/server/content/files/16139e61faa505---35001718181.pdf
    • http://4bx.pl/public/file/82257266472.pdf
    • https://saptabangunmanunggal.com/indomobils/upload/file/76440217424.pdf
    • https://alkoplast.rs/files/norumarinurunenipekif.pdf
    • http://mq-water.net/upload/75559261972.pdf
    • http://aytekinpolatel.com/image/files/79302533069.pdf
    • http://em-mould.com/ckfinder/userfiles/files/xukofojumikiti.pdf
    • https://cokhivietuc.com/img-vietuc/files/41369975967.pdf
    • https://gresathouse.com/wp-content/plugins/super-forms/uploads/php/files/5413f7dd1aeb1beffd3a1d66dffafe55/70530046455.pdf
    • https://visaonline-vn.com/wp-content/plugins/super-forms/uploads/php/files/tmr6davds1ii00mg2h3fpfvj4i/20671879443.pdf
    • https://feedproxy.google.com/~r/Uplcv/~3/YTWXjIUwRh0/uplcv?utm_term=12+week+calisthenics+program+pdf
    • 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://dejavu.sourceforge.net
    • http://dejavu.sourceforge.net/wiki/index.php/License

Extracted artifacts 3

Files carved from inside the sample during analysis.

FilenameKindSourceSize
font_00_sfnt_off0000b31a.bin
9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
pdf-font-stream PDF embedded font (sfnt) at offset 0xB31A 16792 bytes
font_01_sfnt_off0000cb31.bin
2d721f8aa2e98d3343179d4a7da4e0de20c0d48e545bb935c7e245bea58aafb1
pdf-font-stream PDF embedded font (sfnt) at offset 0xCB31 11320 bytes
font_02_sfnt_off0000e58c.bin
fe345fc2dfc7ae49a2fe5e42e79f7a0ad3e5f98f89d356856d725d8d3fdf413b
pdf-font-stream PDF embedded font (sfnt) at offset 0xE58C 14376 bytes