Malicious PDF — malware analysis report

Static analysis result for SHA-256 c35ccfee15745ee8…

MALICIOUS

PDF

79.2 KB Created: 2020-11-26 05:45:17 +02:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 4.8.7)
MD5: f9a7e8201f9c16b72763d5bfdb009970 SHA-1: d3bba27f0cef6784520301f34e3ec16150b0e066 SHA-256: c35ccfee15745ee8bf71a0cbaf86e1854a8713098042b429fb91ff373905b8f5
186 Risk Score

Malware Insights

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

The PDF contains a large number of external links, many pointing to disposable hosting, indicating a link farm or phishing operation. The ClamAV detection and ML classifier strongly suggest malicious intent. While no scripts were explicitly extracted, the PDF structure and embedded URLs are indicative of a phishing or SEO spam campaign designed to redirect users to malicious sites.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9998

Heuristics 6

  • Small PDF contains mass external PDF link farm critical PDF_SEO_LINK_FARM
    Small PDF contains many clickable external PDF links, mostly clustered on one host. This matches generated SEO/link-farm PDF carriers used to route users into malicious or unwanted-software delivery chains, rather than a normal document citation pattern.
  • ClamAV: Pdf.Phishing.Trojan-d2528dad23a95d95-d2528dad23a95d95-10044376-0 critical CLAMAV_DETECTION
    ClamAV detected this file as malware: Pdf.Phishing.Trojan-d2528dad23a95d95-d2528dad23a95d95-10044376-0
  • 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.
  • 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://trafficel.ru/strik?utm_term=us+history+eoc+2021
    • https://cdn-cms.f-static.net/uploads/4418981/normal_5fa5112159f66.pdf
    • https://xujaxivef.weebly.com/uploads/1/3/1/4/131438557/3669821.pdf
    • https://wepusiviji.weebly.com/uploads/1/3/4/6/134661614/zamorivodukadi-jekix-womidirujej.pdf
    • https://wimavikuwoj.weebly.com/uploads/1/3/4/6/134698125/pugil.pdf
    • https://gikigafe.weebly.com/uploads/1/3/4/4/134440869/bca27e.pdf
    • https://lokixesope.weebly.com/uploads/1/3/1/6/131607163/3442074.pdf
    • https://suretazusidik.weebly.com/uploads/1/3/4/0/134012564/954066.pdf
    • https://wusunipusu.weebly.com/uploads/1/3/4/3/134320006/nisalubobemarol_ziwujuses_katoxumizo.pdf
    • https://cdn-cms.f-static.net/uploads/4417658/normal_5f9e4e521c6df.pdf
    • http://www.ascendercorp.com/
    • http://www.ascendercorp.com/typedesigners.html
    • https://s3.amazonaws.com/mokuwanibof/ways_to_find_someone_who_has_died.pdf
    • https://s3.amazonaws.com/fasanag/carrier_water_cooled_chiller_catalogue.pdf
    • https://uploads.strikinglycdn.com/files/09e58f3d-71ea-4c8c-9346-998febf46be0/zodabetexuxonebutigevaw.pdf
    • https://s3.amazonaws.com/numegubowalonan/wuvurifi.pdf
    • https://uploads.strikinglycdn.com/files/7a4f92f9-2ac7-49ba-87b3-2dc5d17b4db4/jenur.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
    • 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_off0000e16d.bin
195f686341ddd8424450eb9e4fee091612aa2cde95ceba4ec4f2375343d0412f
pdf-font-stream PDF embedded font (sfnt) at offset 0xE16D 5064 bytes
font_01_sfnt_off0000f2b6.bin
7d5d75107596ceeb756a133ebebec4cf575eb151202f665d293c2273f9e8e490
pdf-font-stream PDF embedded font (sfnt) at offset 0xF2B6 11232 bytes
font_02_sfnt_off00011914.bin
541fa2b6826b0add99b7d5a173ef1e6a5567607b5192f75b810eb17d6a563501
pdf-font-stream PDF embedded font (sfnt) at offset 0x11914 16204 bytes