Malicious PDF — malware analysis report

Static analysis result for SHA-256 b684a7b5c7a08c1b…

MALICIOUS

PDF

90.9 KB Created: 2021-06-27 23:16:23 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3)
MD5: 307cbbb0285648724c4f4344fa4f0026 SHA-1: 20118b5f21c249bda7d98fd6cfe81d1ea07d568b SHA-256: b684a7b5c7a08c1b387a98e452e8eee4294cb36706d2f00dec35c83d0e9043f9
156 Risk Score

Malware Insights

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

The file was identified as malicious by a machine learning classifier and ClamAV, detecting it as a phishing trojan. Static analysis revealed it functions as a link farm, with numerous URLs pointing to compromised WordPress upload directories and other disposable hosting. These links likely serve as redirects to malicious sites, aiming to trick users into downloading further payloads or submitting sensitive information.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9966

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 http://toshiba-center.ru/uploads/files/govex.pdf
    • https://www.amiunaorchestra.ro/wp-content/plugins/formcraft/file-upload/server/content/files/160c582dd0c149---60522328193.pdf
    • https://cutletsmeat.com/wp-content/plugins/formcraft/file-upload/server/content/files/160ab43c662d8d---24708837143.pdf
    • https://foxtailmag.net/wp-content/plugins/super-forms/uploads/php/files/f3786c1e7c828e43ee776bfc3b8f1c68/kakan.pdf
    • https://www.plsok.com/wp-content/plugins/super-forms/uploads/php/files/a9b11d14f3eed65df595f0e625e0dbec/31394261605.pdf
    • https://riverasphotovideo.com/wp-content/plugins/formcraft/file-upload/server/content/files/16090bf8a88d05---53454559028.pdf
    • http://lotuscourtpune.com/wp-content/plugins/super-forms/uploads/php/files/lleg4l1028m6ajtn4s6lpv45v7/76716009710.pdf
    • https://g3az.com/wp-content/plugins/formcraft/file-upload/server/content/files/1608092502750f---91634357482.pdf
    • http://gf-location.fr/wp-content/plugins/formcraft/file-upload/server/content/files/160947f67319e7---palafuwutowegujujos.pdf
    • https://argumentua.com/i/file/77830277867.pdf
    • http://i-dron.cz/data/file/xibomuxoxuzuresa.pdf
    • http://www.alex-vasilkov.ru/images/wisdom/file/tegawejoti.pdf
    • http://wsm.hk/images/uploadfiles/file/82726297463.pdf
    • http://applexin.com/ttpsea/files/file/xapotud.pdf
    • http://irmascaritasdejesus.org.br/wp-content/plugins/formcraft/file-upload/server/content/files/1606c7f7baa0d6---14260644375.pdf
    • http://www.ellisrasbetonwerke.co.za/wp-content/plugins/formcraft/file-upload/server/content/files/160a206bf24e24---dakigovewaxeluxadun.pdf
    • http://nage-z.com/ckfinder/userfiles/files/1717756947.pdf
    • http://gingerwooddesign.com/wp-content/plugins/formcraft/file-upload/server/content/files/1606f19069f4b3---1060736642.pdf
    • https://www.jemelectric.com/wp-content/plugins/formcraft/file-upload/server/content/files/160b84577754fc---74960535273.pdf
    • http://www.kmclogistics.com/wp-content/plugins/super-forms/uploads/php/files/0c2e5257b28e954a5e92434cec5b2cd4/disugonudazotawewivoxuza.pdf
    • http://quatanggiabao.com/images/uploads/files/88747221277.pdf
    • https://feedproxy.google.com/~r/Uplcv/~3/cv9VXjIrmdE/uplcv?utm_term=bible+scriptures+for+repentance
    • 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_off0000ff08.bin
8347f919d9a0effc55a1c36669a14a63f6dd04cb3f9bc94559227e8b17f30671
pdf-font-stream PDF embedded font (sfnt) at offset 0xFF08 10764 bytes
font_01_sfnt_off000117b1.bin
b3ade6c00296c630cf9c79016626bf04d549e2cec86dc8733f34a7defc1a342e
pdf-font-stream PDF embedded font (sfnt) at offset 0x117B1 17256 bytes
font_02_sfnt_off000144d6.bin
9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
pdf-font-stream PDF embedded font (sfnt) at offset 0x144D6 16792 bytes