Malicious PDF — malware analysis report

Static analysis result for SHA-256 855dbb6717256bdb…

MALICIOUS

PDF

108.7 KB Created: 2021-03-10 01:05:10 +02:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 4.8.7) First seen: 2021-05-22
MD5: 900fbf5d3902a3b9489dfed13347bc87 SHA-1: 7e86db6e5b3e93579693dc70bcdbc1c766b7662a SHA-256: 855dbb6717256bdbbda953af67156f20d43bc13d111240126faf9ca8e3ba6234
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 domains, suggesting a link farm or phishing operation. The ML classifier and ClamAV detection strongly indicate malicious intent. While no scripts were directly extracted, the PDF structure and numerous external URLs are indicative of a phishing or malware distribution attempt, likely initiated via spearphishing attachment.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9990

Heuristics 6

  • 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 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.
  • 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://maypoin.ru/award?keyword=baguio+city+tourist+map+pdf PDF link annotation
    • https://cdn.sqhk.co/pijajawopoji/gWinhi1/agent_orange_victims_vietnam.pdfIn PDF document text
    • http://esclick.pro/3294317008ygemg.pdfIn PDF document text
    • https://cdn.sqhk.co/kovezozeseg/jimANge/54792087907.pdfIn PDF document text
    • http://filemarker.store/94507612754tzff1.pdfIn PDF document text
    • http://ndfnasg.xyz/dometic_rm2652_thermistor_replacement3mp98.pdfIn PDF document text
    • http://potenciy.xyz/tinukadiralewufejilegeruxzm28q.pdfIn PDF document text
    • https://cdn.sqhk.co/busanurutar/jeugfH4/space_rangers_2_mission_guide.pdfIn PDF document text
    • https://cdn.sqhk.co/zekuxemelop/icqOigA/shuddering_fear_synonyms.pdfIn PDF document text
    • http://magnitoli-2ekran.site/wudoraizwvz.pdfIn PDF document text
    • http://deutschebank-meine.com/the_cosmic_doctrine_by_dion_fortuneu0643.pdfIn PDF document text
    • http://azorocheat5.xyz/oral_b_pro_1000_replacement_heads4kue8.pdfIn PDF document text
    • https://cdn.sqhk.co/gulizate/hhLjihi/rovone.pdfIn PDF document text
    • http://makedctl.site/fipalowinusea1nt.pdfIn PDF document text
    • https://cdn.sqhk.co/xenivoronizu/je1OgcF/94468549076.pdfIn PDF document text
    • https://cdn.sqhk.co/ledodatefu/eZhjPgg/fiduragufew.pdfIn PDF document text
    • https://cdn.sqhk.co/xopuwatipo/9Zghhi8/ivory_paint_color_benjamin_moore.pdfIn PDF document text
    • http://dimax.website/whatsapp_plus_new_version_apk_freel7975.pdfIn PDF document text
    • http://mavpa.fun/gomarudufimivegirubisifyoj9.pdfIn PDF document text
    • http://kprovk.xyz/6611200044814ynt.pdfIn PDF document text
    • http://www.ascendercorp.com/In PDF document text
    • http://www.ascendercorp.com/typedesigners.htmlIn PDF document text
    • https://850a36a1-966c-46c3-86ed-e15bcb5778a7.filesusr.com/ugd/ede58b_4ccb68f816d748d9864782665c5f6c8f.pdf?index=trueIn PDF document text
    • https://146c8b6c-0b46-450b-8ed0-b45f1e2a4974.filesusr.com/ugd/b58d21_7216de78b06d463cae7e46f8d82ffa2a.pdf?index=trueIn PDF document text
    • https://1ebfeea1-7d02-43b8-8f0a-002c87bc7f75.filesusr.com/ugd/50dcf6_ccf8d51e34264dbfb97c61270b5f3d18.pdf?index=trueIn PDF document text
    • https://c6f55193-7475-4343-97dd-33cb3b141b6a.filesusr.com/ugd/808d8c_0a4cd52850de4e21ad4d7671deae1681.pdf?index=trueIn PDF document text
    • https://3175e58c-9db9-4d87-bcb9-15e03531d93d.filesusr.com/ugd/c93210_71f70d083fff45a288b79ab4faff20be.pdf?index=trueIn PDF document text
    • http://www.w3.org/1999/02/22-rdf-syntax-ns#In PDF document text
    • http://purl.org/dc/elements/1.1/In PDF document text
    • http://ns.adobe.com/pdf/1.3/In PDF document text
    • http://ns.adobe.com/xap/1.0/In PDF document text
    • http://ns.adobe.com/xap/1.0/mm/In PDF document text
    • http://ns.adobe.com/xap/1.0/rights/In PDF document text
    • http://scripts.sil.org/OFLIn PDF document text

Extracted artifacts 2

Files carved from inside the sample during analysis.

FilenameKindSourceSize
font_00_sfnt_off00016a90.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x16A90 5596 bytes
SHA-256: f18e9dd95b2589e49a5407be9601e0fcf09eee8421d27a2d90a4574df33e9893
font_01_sfnt_off00017d92.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x17D92 11556 bytes
SHA-256: d25805080a694c0911e9956eea9541d2b3fef723b39b4aa0b4177bc0dd763cee