Malicious PDF — malware analysis report

Static analysis result for SHA-256 c1fe71d147620edf…

MALICIOUS

PDF

75.6 KB Created: 2021-06-01 18:30:12 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 4.8.7)
MD5: 0e5e4b40259348ae6e17fb45d21b1b27 SHA-1: d6568939939684bed7c4876ba75cdf4698db45be SHA-256: c1fe71d147620edf21cb0e9a109b541ea4d9563dbca08364220f0f2f68436d4a
186 Risk Score

Malware Insights

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

The PDF contains a large number of external links, identified by the PDF_SEO_LINK_FARM and PDF_SEO_DISPOSABLE_LINK_FARM heuristics. The ML classifier and ClamAV detection strongly indicate malicious intent. The primary URL, 'https://zajinet.ru/123?utm_term=microplastics+in+fish+pdf', suggests a lure related to microplastics, likely to disguise a phishing or malware distribution attempt.

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-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://zajinet.ru/123?utm_term=microplastics+in+fish+pdf
    • https://static.s123-cdn-static.com/uploads/4471706/normal_5fec09aeeec3c.pdf
    • https://pasukanat.weebly.com/uploads/1/3/4/4/134474220/wixedesige_figemufubu_faranegipape.pdf
    • https://padabomax.weebly.com/uploads/1/3/4/6/134681696/rumiguku.pdf
    • https://vodefuba.weebly.com/uploads/1/3/4/6/134688083/9279238.pdf
    • https://cdn-cms.f-static.net/uploads/4409814/normal_60375f641fed2.pdf
    • https://static.s123-cdn-static.com/uploads/4490950/normal_5fdf920017397.pdf
    • https://feroredo.weebly.com/uploads/1/3/1/3/131379294/tozaberul.pdf
    • https://basurujilitafap.weebly.com/uploads/1/3/4/5/134595952/ninikeziwo.pdf
    • https://cdn-cms.f-static.net/uploads/4473963/normal_605bb47cb7815.pdf
    • https://gisoroweri.weebly.com/uploads/1/3/4/8/134893792/ddd667.pdf
    • https://cdn-cms.f-static.net/uploads/4486535/normal_5fd64661f012a.pdf
    • https://cdn-cms.f-static.net/uploads/4443815/normal_600e972349fe4.pdf
    • http://www.ascendercorp.com/
    • http://www.ascendercorp.com/typedesigners.html
    • http://ruwomodanom.pbworks.com/f/68496056328.pdf
    • http://gazumadu.pbworks.com/w/file/fetch/144441402/77131890399.pdf
    • http://lekuzax.pbworks.com/w/file/fetch/144427728/53814893845.pdf
    • http://zekodunu.pbworks.com/w/file/fetch/144465237/how_much_does_a_large_hay_bale_weigh.pdf
    • http://lufokomarib.pbworks.com/f/how_do_you_use_a_tens_unit_for_sciatica.pdf
    • https://uploads.strikinglycdn.com/files/a3aa6ca5-9849-46de-891b-122746aa8f32/25559098415.pdf
    • https://uploads.strikinglycdn.com/files/3d362a3f-7700-4ee6-9b28-4bbdee8413b2/oral-b_pro_1000_electric_toothbrush_with_brush_head_black.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_off0000eaf9.bin
dc486fd24913841fdd9b640c80ba288e22ef8c278c97d436ba6e3adf52ed1864		 pdf-font-stream PDF embedded font (sfnt) at offset 0xEAF9 5248 bytes
font_01_sfnt_off0000fcd8.bin
7e8959cf0a9eabe03ca1cdd3b4701e41ceaf92a2bd1d2a7cccd05b62fa5c1814		 pdf-font-stream PDF embedded font (sfnt) at offset 0xFCD8 10744 bytes

Open this report in the interactive analyzer, or submit your own file for analysis.