Malicious PDF — malware analysis report

Static analysis result for SHA-256 e3ff9551ac4830ed…

MALICIOUS

PDF

85.5 KB Created: 2021-07-04 00:43:06 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3)
MD5: ea11cd3060cc187c443814e4e78b7f88 SHA-1: d2517647deeb41e0488df55180cd305768f34f19 SHA-256: e3ff9551ac4830ed06e22024ee7d91ec649aa9b55964a341e40854298e5aa699
156 Risk Score

Malware Insights

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

This PDF file was flagged as malicious by a machine learning classifier and ClamAV. It contains a link farm pointing to multiple compromised WordPress sites, specifically within the 'super-forms' or 'formcraft' plugin upload directories. These links likely serve as redirects to malicious content or phishing pages. The document body is heavily obfuscated and appears to be generated by wkhtmltopdf, suggesting it's not intended for direct user reading but rather as a vehicle for the embedded links.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9956

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://soba05.org/wp-content/plugins/super-forms/uploads/php/files/8de5087aac0e37cfe1dd00d06c99a1c3/ximepexirije.pdf
    • https://damiel.eu/userfiles/file/19233379364.pdf
    • http://www.misshandicap.ch/wp-content/plugins/formcraft/file-upload/server/content/files/16072d56554bf1---82904313545.pdf
    • https://storage-in-motion.com/wp-content/plugins/formcraft/file-upload/server/content/files/1608b629d7adb3---devonijufefuvedunazosegi.pdf
    • https://digidatadecolombia.com/wp-content/plugins/super-forms/uploads/php/files/02440a1bc0c480efdd192560df48d2a1/temezokavimi.pdf
    • http://www.luminicaambiental.com/wp-content/plugins/formcraft/file-upload/server/content/files/16098b17bb1024---63791670979.pdf
    • http://rusiuojigalvoji.lt/wp-content/plugins/formcraft/file-upload/server/content/files/160b44fa94a4f5---60726372762.pdf
    • https://www.swx.global/wp-content/plugins/super-forms/uploads/php/files/62060174c17ad922a09197715e268142/finon.pdf
    • http://mpti.ru/userfiles/file/7943944510.pdf
    • https://senzedigicraft.com/wp-content/plugins/super-forms/uploads/php/files/37147061c066a3d0704edb8caa33f29b/rodobokinojusinop.pdf
    • https://beribuket.ru/wp-content/plugins/super-forms/uploads/php/files/f412218d57d4be2e3a965934c7a4aecf/84603142296.pdf
    • https://avenue102.com/uploads/file/88362821526.pdf
    • https://esprimagroup.com/userfiles/file/23800061062.pdf
    • https://jennysbooks.com/wp-content/plugins/super-forms/uploads/php/files/1655a7e0f11491f55e72db694245bd68/46946612464.pdf
    • https://eyestech.in/wp-content/plugins/super-forms/uploads/php/files/k2utrt8eh8fnnusm2lpgj00lbp/nurenebozujobekibu.pdf
    • http://ngocvietbungalow.com/upload/files/mobilotabesunibolo.pdf
    • https://www.kiakaha.gr/wp-content/plugins/super-forms/uploads/php/files/33766o4q8ijsavspojlkhhrgk5/luzasenibuwol.pdf
    • http://x04ydivan.ru/userfiles/file/3841042176.pdf
    • https://www.lorenzofranzone.it/wp-content/plugins/super-forms/uploads/php/files/e5b3c265f72f9975eed5bfdd60572406/80709714826.pdf
    • https://bestmiamiturf.com/wp-content/plugins/super-forms/uploads/php/files/8629e25cf267f2f6bb6676dddfd47c0a/45042055667.pdf
    • http://ptk-astana.kz/wp-content/plugins/super-forms/uploads/php/files/38b1675b28f3608dc84c98690cac8236/dutatetubus.pdf
    • http://sam-global.ch/files/file/gosoroledib.pdf
    • http://www.zulfugar.nl/wp-content/plugins/formcraft/file-upload/server/content/files/1606c85a071f92---xojuzib.pdf
    • https://feedproxy.google.com/~r/1eyvgo/aqOO/~3/3CAf4wW3hvY/uplcv?utm_term=colposcopy+during+period
    • 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_off0000ed98.bin
9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
pdf-font-stream PDF embedded font (sfnt) at offset 0xED98 16792 bytes
font_01_sfnt_off000105aa.bin
685acd04d2cf489b44cc9af013edddfcb3e672d7f5ff5f2c24e4a3448edd80d0
pdf-font-stream PDF embedded font (sfnt) at offset 0x105AA 16536 bytes
font_02_sfnt_off00013095.bin
d55b764c0794164cdac5e404c1d33ca4cda1b6a64c961d1be82407405147d957
pdf-font-stream PDF embedded font (sfnt) at offset 0x13095 10676 bytes