Malicious PDF — malware analysis report

Static analysis result for SHA-256 852b015c4619dc5f…

MALICIOUS

PDF

80.6 KB Created: 2021-09-17 22:11:38 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-10-27
MD5: 719cf59e8f4cb15b1bcc96daf3bc6506 SHA-1: 80d1c47429cb404187fc123d7742d4d49dd5ead2 SHA-256: 852b015c4619dc5fc7cfd0aba42e0938ce0f89985bdac9859cf792d7e6ac4ab1
156 Risk Score

Malware Insights

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

The PDF contains numerous links, many of which point to compromised WordPress sites and disposable hosting, suggesting a link farm designed to redirect users to malicious content. The ML classifier and ClamAV detection strongly indicate malicious intent, likely related to phishing or malware distribution. No scripts were extracted, and the document body was unreadable, limiting further analysis of the specific lure.

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 https://www.jahnigterbraak.nl/wp-content/plugins/formcraft/file-upload/server/content/files/1613e504875cf6---bubopa.pdf In PDF document text
    • http://khaskhaan.mn/uploads/userfiles/files/75823270497.pdfIn PDF document text
    • http://zentrumok.com/userfile/files/bexutuloziwamikajavig.pdfIn PDF document text
    • http://cohn-vossen.com/wp-content/plugins/formcraft/file-upload/server/content/files/16131ce1490af2---89285679302.pdfIn PDF document text
    • https://doosradashak.in/ci/userfiles/files/nunolu.pdfIn PDF document text
    • https://weeb.nu/userfiles/file/kuzonepirijupowufazet.pdfIn PDF document text
    • http://bygreenpure.com/userfiles/file/52143512792.pdfIn PDF document text
    • http://intranet.uts.edu.co/portal/app/ckfinder/userfiles/files/bitogononeripixiworoniz.pdfIn PDF document text
    • http://akcihlar.cz/userfiles/file/buzapuna.pdfIn PDF document text
    • http://hutnia.pl/userfiles/file/46659912745.pdfIn PDF document text
    • http://rigassprotes.lv/uploadz/file/kuwutajudejij.pdfIn PDF document text
    • http://ttccid.com/userfiles/files/timabupalobosuxufaneg.pdfIn PDF document text
    • http://ttlengenharia.com.br/wp-content/plugins/formcraft/file-upload/server/content/files/161372e2a2c638---31531937568.pdfIn PDF document text
    • http://lor-rostov.su/userfiles/files/xilugepabezasedit.pdfIn PDF document text
    • http://haliburtonhighlandsheritage.ca/userfiles/file/26056803825.pdfIn PDF document text
    • http://xn--80aadq3ae7aa5k.xn--p1ai/upload/file/dulive.pdfIn PDF document text
    • http://rheinmotel.com/userfiles/file/72240882297.pdfIn PDF document text
    • http://cutskytools.com/d/files/3175067441.pdfIn PDF document text
    • http://joeun-it.com/userData/board/file/refego.pdfIn PDF document text
    • http://tamilannuaire.com/var/www/vhosts/vps296430.ovh.net/tamilannuaire.com/images/file/terofarazej.pdfIn PDF document text
    • http://www.superior-inkjet.com/login/ckfinder/userfiles/files/witadonodiwi.pdfIn PDF document text
    • https://mujeresenmovimientoplus.com/userfiles/file/digakezusinazoselipejexet.pdfIn PDF document text
    • https://feedproxy.google.com/~r/Uplcv/~3/6naE_Nh8_CY/uplcv?utm_term=how+to+change+apps+name+in+androidPDF link annotation
    • 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://dejavu.sourceforge.netIn PDF document text
    • http://dejavu.sourceforge.net/wiki/index.php/LicenseIn PDF document text

Extracted artifacts 3

Files carved from inside the sample during analysis.

FilenameKindSourceSize
font_00_sfnt_off0000d6ae.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xD6AE 17516 bytes
SHA-256: 380dae052099b09022e426720d58e5a5ed938c3e7f09f834c72ad74a26cf0867
font_01_sfnt_off000103a8.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x103A8 10992 bytes
SHA-256: bbbd1676f4b1e164c5147009f5e37693b855f7bd421d4bce5dd77cc53b8fcbba
font_02_sfnt_off00011cd4.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x11CD4 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1