Malicious PDF — malware analysis report

Static analysis result for SHA-256 c8e16ee5ceef64fd…

MALICIOUS

PDF

75.5 KB Created: 2021-05-16 12:18:55 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 4.8.7)
MD5: 00371d0b7a9051ef5341110a3ad7aad2 SHA-1: 4e3385bfa1c4c9933f2f2d5ff4cc6d54631de463 SHA-256: c8e16ee5ceef64fd3f412882962b346c4ffe149ed1dd910f2bf5f74ba8a4e7c3
196 Risk Score

Malware Insights

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

This PDF file was detected as malicious by ClamAV and an ML classifier. It contains numerous links to external websites, many hosted on compromised WordPress installations or disposable domains, suggesting a phishing or malware distribution campaign. The presence of embedded URLs and the nature of the heuristics indicate that the primary function is to redirect users to potentially harmful content.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9999

Heuristics 7

  • 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 to algorithmically-generated URL high PDF_RANDOM_URL_LINK
    PDF contains a clickable HTTP(S) link whose host looks algorithmically generated (pronounceable-random labels) and whose path/query carries a long high-entropy token. This is the randomized-redirector pattern of malspam phishing lures — the visible document is only a prompt — not a PDF parser vulnerability.
  • 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://inwebjor.ru/uplcv?utm_term=advanced+conjunctions+exercises+with+answers+pdf
    • https://uleshuzataruhaz.hu/files/file/96383812158.pdf
    • http://anandamsanyal.com/userfiles/file/runibujevu.pdf
    • http://www.thebetterinsurance.com/wp-content/plugins/formcraft/file-upload/server/content/files/16081117472cd0---xipemelovur.pdf
    • https://kindliving.org/wp-content/plugins/super-forms/uploads/php/files/tmp/wugobuwa.pdf
    • http://akicgiyim.com/userfiles/file/vosofure.pdf
    • https://burmesecatclub.nz/wp-content/plugins/super-forms/uploads/php/files/0c319dbf6a5cc3087c14b57826a803e1/goxubogavopoxuvuzoto.pdf
    • https://ailani.org/wp-content/plugins/super-forms/uploads/php/files/f1829549f57a0eb824e741bc53400242/94896296010.pdf
    • http://www.sunarnuricomuisvealisverismerkezi.com/wp-content/plugins/super-forms/uploads/php/files/m7m63b9l17m8aoefnr35g4mr62/jixokoraro.pdf
    • https://rffsev.ru/wp-content/plugins/super-forms/uploads/php/files/e9fe04f15f8f5673608c1997a7d92fa6/tonalowixuwejikuzifogut.pdf
    • http://theydeserveastamp.org/wp-content/plugins/formcraft/file-upload/server/content/files/1607ec8df8c632---xuvupovekunuge.pdf
    • http://barrarioservicos.com.br/wp-content/plugins/formcraft/file-upload/server/content/files/1607fc168a2f9f---70854351613.pdf
    • https://glosunspa.com/wp-content/plugins/formcraft/file-upload/server/content/files/1607230b4e113c---rufepapumi.pdf
    • http://adanateknikservis.web.tr/wp-content/plugins/formcraft/file-upload/server/content/files/16075c25f9f101---kawijazezubufatazaxep.pdf
    • https://www.okcfarmersmarket.com/wp-content/plugins/super-forms/uploads/php/files/5ba5002ef461779dc46972afad34eb58/37334034044.pdf
    • https://ceilford.org/wp-content/plugins/super-forms/uploads/php/files/c934fcd8d1d558bd4c88893adeda6886/70355716656.pdf
    • http://ophtalmic-overnight.fr/wp-content/plugins/formcraft/file-upload/server/content/files/1609a326b1a990---22669039605.pdf
    • https://tecnibat.net/uploads/archivos/70045472728.pdf
    • http://www.ascendercorp.com/
    • http://www.ascendercorp.com/typedesigners.html
    • 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_off0000e85d.bin
6e1b64b198367b52b6ae2af252af6106a30b9e14d7337a70adae9ad12a332faf
pdf-font-stream PDF embedded font (sfnt) at offset 0xE85D 5496 bytes
font_01_sfnt_off0000fb28.bin
d0ff86f62b0f35c89e14aaa35921c50a89277ce971dda77aec2a291ba94422a2
pdf-font-stream PDF embedded font (sfnt) at offset 0xFB28 11060 bytes