Malicious PDF — malware analysis report

Static analysis result for SHA-256 39bdbc59bc08c3d3…

MALICIOUS

PDF

78.7 KB Created: 2021-04-20 06:04:44 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 4.8.7) First seen: 2021-11-25
MD5: 1899f41f1bf4d73e0a475200d94c30ac SHA-1: 26b0a05ef02d7c1a532731740e4e8b91a64294d6 SHA-256: 39bdbc59bc08c3d3d52eeb33b73e87e25c21eda17f6983492a4931f95140cae2
186 Risk Score

Malware Insights

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

The PDF contains a large number of external links, identified as a link farm, with several pointing to potentially malicious domains. The ClamAV detection and ML classifier strongly indicate malicious intent, likely related to phishing or malware distribution via these external links. The document body is heavily obfuscated and contains metadata suggesting it was generated by wkhtmltopdf, which is not typical for legitimate documents.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9997

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://jottigo.ru/strik?utm_term=rune+magic+build+outward PDF link annotation
    • http://raisinshub.club/how_do_i_cancel_wall_street_journal_subscription9yzew.pdfIn PDF document text
    • https://cdn-cms.f-static.net/uploads/4412158/normal_60267c82549f0.pdfIn PDF document text
    • https://fopojikanerev.weebly.com/uploads/1/3/4/8/134888820/0036e371c09d7f.pdfIn PDF document text
    • https://cdn-cms.f-static.net/uploads/4376380/normal_6052cced1d9ab.pdfIn PDF document text
    • https://gexuxufe.weebly.com/uploads/1/3/1/4/131406387/gamutoza.pdfIn PDF document text
    • https://muzuxagofonokow.weebly.com/uploads/1/3/1/4/131406885/592ca0ac8b2b993.pdfIn PDF document text
    • https://mebedepubini.weebly.com/uploads/1/3/0/8/130813558/0214c69073694.pdfIn PDF document text
    • https://static.s123-cdn-static.com/uploads/4473384/normal_5fcaa3506a1cd.pdfIn PDF document text
    • http://help-violation.com/evicted_book_chapter_9_summary36hx3.pdfIn PDF document text
    • http://instapresent.site/tibepitodepevomasidhfp0.pdfIn PDF document text
    • http://afracheat6.xyz/tizivetazegapojowga8a.pdfIn PDF document text
    • http://generalmassage.online/anouilh_medeapwwtb.pdfIn PDF document text
    • https://static.s123-cdn-static.com/uploads/4470832/normal_6008fa36bfbd4.pdfIn PDF document text
    • http://www.ascendercorp.com/In PDF document text
    • http://www.ascendercorp.com/typedesigners.htmlIn PDF document text
    • https://b0cee159-9ce3-47d2-9452-de9e383f1b6b.filesusr.com/ugd/fac5c7_59733e77e6394100a719ec4f75591ab6.pdf?index=trueIn PDF document text
    • https://6a543b89-810f-4a07-932c-4cc129fc401a.filesusr.com/ugd/1e5726_51650f1b8404490bbf5d990a72a7d9ac.pdf?index=trueIn PDF document text
    • https://c3438639-6a75-4920-aa4f-d1e0b619354f.filesusr.com/ugd/3be3a7_a3c13978a010418f9e105d908ffc1aff.pdf?index=trueIn PDF document text
    • https://2903667b-e544-4972-ac7f-e5855aaa9b37.filesusr.com/ugd/2cc660_ec87b1ea3d3e490a81a72486184b8f23.pdf?index=trueIn PDF document text
    • http://mivetafo.epizy.com/american_gods_season_1_episode_7_review.pdfIn PDF document text
    • http://xoxejafomi.rf.gd/janujuwibobu.pdfIn PDF document text
    • http://bukaduxanob.epizy.com/90855306379.pdfIn PDF document text
    • http://kowisefofob.epizy.com/69337686412.pdfIn 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_off0000f88d.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xF88D 5320 bytes
SHA-256: 47cb898acf12b1860536441a590288782a47114abd070e2274a54b32ca2422b5
font_01_sfnt_off00010a9f.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x10A9F 10340 bytes
SHA-256: e83c2c9307e1c069f3bec56bf63957a317c061a96343f75b6cd51122573d22ae