Malicious PDF — malware analysis report

Static analysis result for SHA-256 c3a958aaf51d20db…

MALICIOUS

PDF

88.0 KB Created: 2021-07-27 22:10:24 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3)
MD5: 3055b32a2a7f04755fa76eb77e28c7c3 SHA-1: 421141eb41ea87eceb098a93dbdf9647cb1e1528 SHA-256: c3a958aaf51d20dbf05fbecbcc784cb6e0d3d0bef305467e18eacce52bdaf5f3
156 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment

The sample was detected as malicious by ClamAV and an ML classifier, indicating a high likelihood of malicious intent. The PDF contains numerous links, many pointing to compromised WordPress sites, suggesting a link farm used for phishing or malware distribution. The presence of embedded URLs and the nature of the heuristics strongly suggest this document is part of a phishing campaign, likely using spearphishing attachments as the initial access vector.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9972

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://www.pirac.org/wp-content/plugins/super-forms/uploads/php/files/2b3b47ab7effeb0ebdd6036b80124e6b/35178147946.pdf
    • https://playerpress.com/ckfinder/userfiles/files/33024600614.pdf
    • https://www.vigo.co.za/wp-content/plugins/formcraft/file-upload/server/content/files/160cc561787950---motowaxemasor.pdf
    • https://belgradenightlife.info/wp-content/plugins/super-forms/uploads/php/files/39fj9vhc7u8mduv5gclsadknit/38413675787.pdf
    • http://www.aluvascientific.com/UserFiles/file/gopevorakubarowivamilesib.pdf
    • http://planetamama.ru/files/file/tavenoxebutiniro.pdf
    • https://www.breastcancerfoundation.in/wp-content/plugins/super-forms/uploads/php/files/f4f6824da75374826d308f564a627083/63336983009.pdf
    • https://www.saltriot.com/wp-content/plugins/super-forms/uploads/php/files/c60bd7557fa95b72c5f0b89c1c92d839/53027653956.pdf
    • https://kakvkusno26.ru/wp-content/plugins/super-forms/uploads/php/files/80100689629ede727d902434452e6135/52271745759.pdf
    • https://beaszemin.com/files/lolorim.pdf
    • https://www.scanworld.se/wp-content/plugins/formcraft/file-upload/server/content/files/160c652fff278e---88834541889.pdf
    • http://kingspec.su/wp-content/plugins/super-forms/uploads/php/files/mf7qpdi83ucjv49rfee92p30n8/dagenizizugozefijipe.pdf
    • https://senhewood.com/d/files/19066072103.pdf
    • http://babamoleskine.com/files/file/50347360985.pdf
    • http://jtour.vn/userfiles/file/82751931342.pdf
    • https://www.enviedecrire.com/wp-content/plugins/formcraft/file-upload/server/content/files/160922c9d4aa80---54400512891.pdf
    • http://mictrogiang.com/userfiles/files/xutiwekitukagolowesotiza.pdf
    • http://hphs1958reunion.com/clients/47465/File/2236554628.pdf
    • https://chameleoncoupons.com/adgprocessing/uploads/files/61372575703.pdf
    • http://andreagarciam.com/wp-content/plugins/formcraft/file-upload/server/content/files/16080a63285e34---48869535840.pdf
    • http://www.majorisinvestimentos.com.br/wp-content/plugins/formcraft/file-upload/server/content/files/1607e4af875628---bifepuduvijanoboda.pdf
    • https://tkpmission.org/wp-content/plugins/formcraft/file-upload/server/content/files/1607ec9648b784---54290175928.pdf
    • https://www.hamburgeriaagricola.com/wp-content/plugins/super-forms/uploads/php/files/6rg4e26c6e6cjns4qfhmulrai3/velafutuv.pdf
    • https://eclipsetheaters.com/wp-content/plugins/formcraft/file-upload/server/content/files/16087c1ef03919---posiba.pdf
    • https://bowenpainter.com/wp-content/plugins/formcraft/file-upload/server/content/files/160966c2654f58---73087605304.pdf
    • https://feedproxy.google.com/~r/skout/mBVl/~3/LPIa9PGmDLg/uplcv?utm_term=online+store+business+plan+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_off0000f4b4.bin
a770d5073da2742b1f390c0d32ec0c41926142b9a765ef5f68d34eda5ffb5e7c
pdf-font-stream PDF embedded font (sfnt) at offset 0xF4B4 16740 bytes
font_01_sfnt_off00012034.bin
0d6cbd1219b714f8c2a3b73a0d47f0a782ce2f74678177d5ffcf2d58fcfa5dd4
pdf-font-stream PDF embedded font (sfnt) at offset 0x12034 10756 bytes
font_02_sfnt_off000138d9.bin
9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
pdf-font-stream PDF embedded font (sfnt) at offset 0x138D9 16792 bytes