Malicious PDF — malware analysis report

Static analysis result for SHA-256 5c3cd33e3eff5fea…

MALICIOUS

PDF

78.4 KB Created: 2021-09-13 20:49:28 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3)
MD5: a6954c3f86c99b96d71160582a8bd937 SHA-1: d8e12a01f713f6e0957cc871049e067d38488afb SHA-256: 5c3cd33e3eff5fea2231f6907e1de3f231bcbcbe58a4d1412b06ccaa1908b5da
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 or disposable hosting services, indicating a link farm designed to redirect users. The ML classifier and ClamAV detection strongly suggest malicious intent, likely for phishing or distributing further malware. The presence of a link farm on potentially compromised CMS uploads and disposable hosting reinforces this assessment.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9968

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 http://dija.lv/public/userfiles/file/waxajaridabipuzokusug.pdf
    • http://eastendmediation.com/customer/3/d/9/3d947ad6ce2568d98b832ccf5548371bFile/50187575303.pdf
    • https://www.mercato.co.za/wp-content/plugins/formcraft/file-upload/server/content/files/16139d5b7da822---zezajiralakuwulisekadij.pdf
    • http://tipiland.net/upload/file/92909430974.pdf
    • https://ventana-sur.com/wp-content/plugins/formcraft/file-upload/server/content/files/16133aaf97c457.pdf
    • http://recrute.fr/files/files/44777811559.pdf
    • http://bibonatura.com/ckfinder/userfiles/files/zugolo.pdf
    • http://raczcsalad.hu/files/mujamolaval.pdf
    • https://n-v-v.dk/userfiles/file/kexejewow.pdf
    • https://reviewz.eu/app/webroot/files/userfiles/files/13105209334.pdf
    • https://zhansq.cn/upload/file/polem.pdf
    • https://braviengenharia.com.br/wp-content/plugins/super-forms/uploads/php/files/4250b5fckr11hhr7egttfap5db/86082717847.pdf
    • http://zygzak.eu/foto_dane/wysiwyg/File/dafuvimojilapos.pdf
    • https://hebatkeren88.com/contents/files/2051108984.pdf
    • http://galantemontagnana.it/ckfinder/userfiles/files/50225776266.pdf
    • https://www.multilandtours.com/assets/ckfinder/userfiles/files/sefabigafarapanu.pdf
    • https://www.smartfutureexpo.com/ckfinder/userfiles/files/sirowekabironum.pdf
    • https://norservis.com/files/files/rejulaji.pdf
    • http://uat.ideadunes.com/projects/ideadunes-portfolio-site/wp-content/plugins/formcraft/file-upload/server/content/files/161353bdc519f2---20923640882.pdf
    • http://vanguardhungary.hu/userfiles/file/rilajizaxofopo.pdf
    • http://paoladebenedetti.eu/userfiles/files/kukijezenafur.pdf
    • http://atut-biuro.com/uploaded/file/17472175636.pdf
    • https://feedproxy.google.com/~r/skout/mBVl/~3/6naE_Nh8_CY/uplcv?utm_term=extreme+motorbike+jump+3d+mod+apk
    • 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_off0000c8c0.bin
e687a68ecd9095a32eed6038c65c859ff6f5d6b9f43aa6e0b6a245b6e9d2beb9
pdf-font-stream PDF embedded font (sfnt) at offset 0xC8C0 10956 bytes
font_01_sfnt_off0000e1ef.bin
af9103993270f8307bcfb95302e64fc9a829954374f67160f2a1e9c3428205d8
pdf-font-stream PDF embedded font (sfnt) at offset 0xE1EF 18940 bytes
font_02_sfnt_off000113fd.bin
9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
pdf-font-stream PDF embedded font (sfnt) at offset 0x113FD 16792 bytes