Malicious PDF — malware analysis report

Static analysis result for SHA-256 031b89bff62a59dc…

MALICIOUS

PDF

86.4 KB Created: 2021-08-16 03:48:02 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-11-03
MD5: 1e0c45c4aff2b1d84d44d52b4756cd9b SHA-1: 7b7e500e527f30a1642c41b708d8172b1b0a7d86 SHA-256: 031b89bff62a59dcccde769bec0357ff610c1859be0e837b544092543e97c5dd
156 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment T1204.002 Malicious Link

The file was detected as malicious by ClamAV and an ML classifier, indicating a high likelihood of malicious intent. It contains numerous links, many pointing to compromised CMS upload directories or disposable hosting, suggesting a link farm designed to redirect users. The PDF's structure and the presence of multiple external URIs strongly indicate it's used as a lure to lead victims to potentially malicious content hosted elsewhere.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9990

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://diakmelo.hu/ckfinder/userfiles/files/sasoze.pdf In PDF document text
    • http://bloemenwinkelindex.nl/images/uploads/marunelasawavonume.pdfIn PDF document text
    • https://www.stjohnhomelessshelter.org/wp-content/plugins/super-forms/uploads/php/files/fcc693a3cc3f1c7b9215744677197345/83840602384.pdfIn PDF document text
    • http://metabolit-plus.ru/files/file/nezurevomase.pdfIn PDF document text
    • http://boulderdivorcelaw.com/wp-content/plugins/formcraft/file-upload/server/content/files/160714253774c5---21568105134.pdfIn PDF document text
    • http://mbcasc.net/imgs/file/vevuwe.pdfIn PDF document text
    • https://bdblue.com/ckfinder/userfiles/files/kuledobosoxibije.pdfIn PDF document text
    • http://hopkins1983.com/clients/861771/File/66721569187.pdfIn PDF document text
    • http://decamiones.com/userfiles/file/jomonarabefoj.pdfIn PDF document text
    • http://zechnerbau.at/images/content/files/71705179580.pdfIn PDF document text
    • http://sarlampa.ru/upload_picture/46025679351.pdfIn PDF document text
    • http://www.uvhk.com/wp-content/plugins/formcraft/file-upload/server/content/files/160cbf491c408a---rowipuzagimejax.pdfIn PDF document text
    • http://importfoodfair.com/userfiles/image/2021/07/file/94236962629.pdfIn PDF document text
    • http://thedewakohchang.com/image/upload/File/5702695885.pdfIn PDF document text
    • https://pinotcar.com/wp-content/plugins/super-forms/uploads/php/files/e5347fdc98acd19017d023e1aface879/difaropulakuduwota.pdfIn PDF document text
    • http://atraba-holding.com/userfiles/file/dubelavaxefudigalopavun.pdfIn PDF document text
    • https://tecsal.com.br/wp-content/plugins/formcraft/file-upload/server/content/files/160d56b600706a---birijesam.pdfIn PDF document text
    • http://dambi.pl/userfiles/file/56795676050.pdfIn PDF document text
    • http://www.kroonzuivel.nl/ckfinder/userfiles/files/gamirubonejipa.pdfIn PDF document text
    • http://seoulsquare.com/userfiles/file/19629027594.pdfIn PDF document text
    • https://lajovisena.com/gallery/file/zumol.pdfIn PDF document text
    • https://duproject.com/uploadEditor/files/kodiwipaluw.pdfIn PDF document text
    • https://pabausa.org/wp-content/plugins/formcraft/file-upload/server/content/files/160810236a9368---tapukujadutulotezuka.pdfIn PDF document text
    • http://rent2day.ca/ci2/userfiles/files/ziruvosomamurafi.pdfIn PDF document text
    • https://feedproxy.google.com/~r/skout/mBVl/~3/3vuEKuznOb8/uplcv?utm_term=sistema+de+inyeccion+electronica+gasolina+pdfPDF 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_off0000eb92.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xEB92 17300 bytes
SHA-256: ccd32b52769c2e61a250ee0a6d5b37b2a00454bbf732ddbcb6d989a5e57e29d7
font_01_sfnt_off0001176c.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x1176C 11152 bytes
SHA-256: e5d43a7ec72dffc292fc021ab333d7747a97be61c83b26859e322c53d82a3c9e
font_02_sfnt_off00013148.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x13148 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1