Malicious PDF — malware analysis report

Static analysis result for SHA-256 8d88545803b16186…

MALICIOUS

PDF

70.2 KB Created: 2021-01-13 21:19:17 +02:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 4.8.7)
MD5: 5fdfe88ef021573d556036d161ed0ef0 SHA-1: 7bbf87a0765f37ed3f14da60f85582a970514939 SHA-256: 8d88545803b16186137bda68f44670cf623dbc8154ab1b3cdcb7e7ecb6d8a308
184 Risk Score

Malware Insights

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

The PDF contains multiple embedded URLs, with at least one pointing to known malicious redirector infrastructure ('traffmen.ru'). The heuristic 'PDF_SEO_DISPOSABLE_LINK_FARM' indicates a pattern of using disposable hosting for link farms, further suggesting malicious intent. The ML classifier and ClamAV detection strongly support the malicious verdict.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9995

Heuristics 5

  • PDF links to known malicious redirector infrastructure critical PDF_MALICIOUS_REDIRECTOR_LINK
    PDF contains a clickable URI to redirector infrastructure used by a known malicious PDF SEO/adware delivery campaign. These documents typically rely on user interaction and redirect chains rather than a PDF parser vulnerability.
  • ClamAV: Pdf.Phishing.Trojan-d2568dad23a94d95-d2568dad23a94d95-10044375-0 critical CLAMAV_DETECTION
    ClamAV detected this file as malware: Pdf.Phishing.Trojan-d2568dad23a94d95-d2568dad23a94d95-10044375-0
  • 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.
  • 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://traffmen.ru/123?utm_term=walt+clark+middle+school+plant+sale
    • https://cdn.sqhk.co/dipujabuxiw/e5Cgdjj/sumezudosoli.pdf
    • https://site-1168430.mozfiles.com/files/1168430/22767682906.pdf
    • https://duveniwapawas.weebly.com/uploads/1/3/4/2/134265961/7133784.pdf
    • https://site-1177407.mozfiles.com/files/1177407/fall_dudes_3d_early_access.pdf
    • https://site-1175635.mozfiles.com/files/1175635/antigona_jean_anouilh.pdf
    • https://site-1168066.mozfiles.com/files/1168066/69857912508.pdf
    • https://site-1187532.mozfiles.com/files/1187532/81513439770.pdf
    • https://site-1084153.mozfiles.com/files/1084153/minigame_minecraft_pe_download.pdf
    • http://www.ascendercorp.com/
    • http://www.ascendercorp.com/typedesigners.html
    • https://s3.amazonaws.com/resixexi/anticoagulation_endoscopy_guidelines.pdf
    • https://s3.amazonaws.com/semuxemakaw/calderas_acuotubulares.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_off0000d470.bin
cf369baf857ba773cfe6ee841e7f5dfdfd1722f6c3cad854630054069857d9d6
pdf-font-stream PDF embedded font (sfnt) at offset 0xD470 5392 bytes
font_01_sfnt_off0000e6a4.bin
ece4ea08882e1409e87455bf9c1d1d00267ff14304106353289b90db35d0d3fa
pdf-font-stream PDF embedded font (sfnt) at offset 0xE6A4 11092 bytes