Malicious PDF — malware analysis report

Static analysis result for SHA-256 fd39b6373d3a769e…

MALICIOUS

PDF

86.4 KB Created: 2021-03-16 17:13:45 +02:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 4.8.7) First seen: 2021-10-12
MD5: 633cfcaaae8582b03329097a710fbb93 SHA-1: 58b9d63e51ec3be1a8232bfea7d2b6c4fe9a5cce SHA-256: fd39b6373d3a769eddf9c876e6e35214302f3191ce31dc75f097984b9d407a90
126 Risk Score

Malware Insights

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

The PDF file was flagged by ML classifiers and ClamAV as malicious, specifically as a phishing trojan. It contains numerous embedded URIs, many of which point to disposable or unknown domains, suggesting a link farm or phishing lure. The document body, though heavily obfuscated, contains text related to scientific articles and the wkhtmltopdf application, likely serving as a pretext to disguise the malicious intent of redirecting users to potentially harmful websites.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9997

Heuristics 5

  • 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.
  • 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://gimoguvi.ru/award?keyword=articulos+cientificos+de+agronomia+en+ingles+pdf PDF link annotation
    • http://mumolazesinidix.getenjoyment.net/61505560894.pdfIn PDF document text
    • https://cdn-cms.f-static.net/uploads/4378160/normal_6028a25755495.pdfIn PDF document text
    • https://cdn-cms.f-static.net/uploads/4468831/normal_603888a4bebc5.pdfIn PDF document text
    • https://cdn.sqhk.co/tategupet/gfLgfia/xojitititegikikelo.pdfIn PDF document text
    • https://cdn.sqhk.co/dijobika/ZPifagj/girls_frontline_2_release.pdfIn PDF document text
    • https://static.s123-cdn-static.com/uploads/4444356/normal_60000fbbafa2c.pdfIn PDF document text
    • https://cdn-cms.f-static.net/uploads/4457011/normal_5fe9af53a90dc.pdfIn PDF document text
    • https://cdn-cms.f-static.net/uploads/4365657/normal_600a91202df5c.pdfIn PDF document text
    • http://lapitubemexidi.mywebcommunity.org/elements_of_writing_ppt.pdfIn PDF document text
    • http://xonitaj.mywebcommunity.org/diarios_de_motocicleta_movie.pdfIn PDF document text
    • https://cdn.sqhk.co/dabozijide/aFFPhbW/juvijogexasadilona.pdfIn PDF document text
    • https://cdn-cms.f-static.net/uploads/4391314/normal_60466886e1d7d.pdfIn PDF document text
    • https://static.s123-cdn-static.com/uploads/4449779/normal_5fcf681c6654b.pdfIn PDF document text
    • https://cdn-cms.f-static.net/uploads/4485016/normal_6010fccf609c3.pdfIn PDF document text
    • https://static.s123-cdn-static.com/uploads/4415964/normal_5fe54937d84c7.pdfIn PDF document text
    • http://www.ascendercorp.com/In PDF document text
    • http://www.ascendercorp.com/typedesigners.htmlIn PDF document text
    • https://uploads.strikinglycdn.com/files/5585959b-336b-4a1c-b721-fc687fe249d3/how_long_do_dyson_rechargeable_batteries_last.pdfIn PDF document text
    • https://uploads.strikinglycdn.com/files/9c2d76f9-1232-4bfb-ada5-88e975936c60/30540249146.pdfIn PDF document text
    • https://uploads.strikinglycdn.com/files/d97687ba-e933-41d1-936d-a2ded4a0c7d6/how_to_light_a_kerosene_heater_manually.pdfIn PDF document text
    • http://liraperuwuw.atwebpages.com/fevegen.pdfIn PDF document text
    • https://uploads.strikinglycdn.com/files/e4ae3174-a65d-4662-8095-bf58820489d3/rubolakape.pdfIn PDF document text
    • https://uploads.strikinglycdn.com/files/9148059b-c190-481c-821a-33734f5c7a5a/16315836038.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_off000112a7.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x112A7 5464 bytes
SHA-256: a6fb8eaa1eb5c4443fa0944d69b85a84cb0802988eb8b99b670fd391cdd1ecee
font_01_sfnt_off00012527.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x12527 11368 bytes
SHA-256: 78654297d75fff8942bcbc0127eb99ec93a05202d1ce7e192d7db6411fbbceb5