Malicious PDF — malware analysis report

Static analysis result for SHA-256 f57b32fd27fd88a6…

MALICIOUS

PDF

73.3 KB Created: 2021-06-12 18:06:09 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 4.8.7)
MD5: 0a8b9727970edb024f474b9f7ba31c16 SHA-1: ff0406178ea0d0b6f9c847319d9bf024306e9004 SHA-256: f57b32fd27fd88a6bba7824e61cf4e43b050a352aa5be8fb3de4b00a38a96228
156 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment T1059.007 JavaScript

The sample is detected as malicious by ClamAV and an ML classifier, indicating a high likelihood of malicious intent. It contains numerous external links, many pointing to compromised CMS upload directories or disposable hosting, suggesting a link farm designed to redirect users to malicious sites. The presence of embedded URLs and the PDF_SEO_DISPOSABLE_LINK_FARM heuristic further support this, indicating the document's primary purpose is to drive traffic to external, potentially harmful, resources.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9998

Heuristics 6

  • ClamAV: Pdf.Phishing.Trojan-d2528dad23a95d95-d2528dad23a95d95-10044376-0 critical CLAMAV_DETECTION
    ClamAV detected this file as malware: Pdf.Phishing.Trojan-d2528dad23a95d95-d2528dad23a95d95-10044376-0
  • 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://oniceh.ru/uplcv?utm_term=a+boogie+99+problems+lyrics
    • https://pasarantogeldua.com/contents//files/pusejuzeligegomelezoned.pdf
    • https://selectwifi.com/wp-content/plugins/formcraft/file-upload/server/content/files/1607bda24b542b---solujadovu.pdf
    • https://pinpointfeedtech.com/ckfinder/userfiles/files/85017257381.pdf
    • http://www.1000ena.com/wp-content/plugins/formcraft/file-upload/server/content/files/160803d85b3f51---kizemela.pdf
    • https://www.officinadelgustoroma.com/wp-content/plugins/super-forms/uploads/php/files/0cd297502341e1bc44218089930cb7ca/33589121965.pdf
    • https://absolut-fit-and-dance.de/wp-content/plugins/super-forms/uploads/php/files/145eekancjj9p17q6r1lotr4am/66347042812.pdf
    • http://www.miamiairportlimo.net/wp-content/plugins/formcraft/file-upload/server/content/files/16081627aaaaeb---rojanejemilizowojef.pdf
    • http://antik-cafe-bergen.de/wp-content/plugins/formcraft/file-upload/server/content/files/160a242553bfc6---tivuzolugibog.pdf
    • https://zlatartopalovic.rs//files/4092909725.pdf
    • http://ahxxzx.com/userfiles/202105/file/sogawabekotizeligozukale.pdf
    • https://camping-du-lac-dijon.com/fichiers/dofafaz.pdf
    • https://studio45.live/wp-content/plugins/super-forms/uploads/php/files/t2voo96n84cblssnua1cjvqf5t/35918096925.pdf
    • http://www.dadosefatos.net.br/wp-content/plugins/formcraft/file-upload/server/content/files/160ab753fc81c1---10028106645.pdf
    • https://jjmassociates.com/wp-content/plugins/super-forms/uploads/php/files/1afcdeeac35cc4bce80e511d4c0bb5f3/42357108174.pdf
    • http://younewstoday.com/task/userimages/file/31158035797.pdf
    • http://www.hollyskauaicondo.com/wp-content/plugins/formcraft/file-upload/server/content/files/160743d302e7b4---tosonomubaxukutijupan.pdf
    • https://performanceltg.com/wp-content/plugins/super-forms/uploads/php/files/6d0a4db9936da08bb26c1f039f8029bd/bisofikorigokomufipon.pdf
    • http://www.ascendercorp.com/
    • http://www.ascendercorp.com/typedesigners.html
    • http://lovewhereyoulv.wpengine.com/wp-content/plugins/super-forms/uploads/php/files/73e6c83eb6c24f053642be2dd3d82eaf/xiluvusaxaveribijewe.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://scripts.sil.org/OFL

Extracted artifacts 2

Files carved from inside the sample during analysis.

FilenameKindSourceSize
font_00_sfnt_off0000df41.bin
af6fe7f5f8fb31fd9e6fa0133dff3a593191f40961ffbf2c134c56aa123fd0a7
pdf-font-stream PDF embedded font (sfnt) at offset 0xDF41 5432 bytes
font_01_sfnt_off0000f1b9.bin
5a99c8f305f4c610d0125d2b19b6a6503746b6029407cd190a468de59ad206f6
pdf-font-stream PDF embedded font (sfnt) at offset 0xF1B9 10848 bytes