Malicious PDF — malware analysis report

Static analysis result for SHA-256 315f9e9293b6e78a…

MALICIOUS

PDF

68.3 KB Created: 2021-04-07 18:40:41 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 4.8.7) First seen: 2021-11-25
MD5: 4041beaec28e67e8e0ffd93d98e75d82 SHA-1: a92f23ee1b088c87cb4eeafbbe597df9664c6bc1 SHA-256: 315f9e9293b6e78acc257d198543379976cfe4b7a82d0db7cc35114f688617ed
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, and includes a UTM term that suggests it is part of an SEO link farm. The ML classifier and ClamAV detection strongly indicate malicious intent, likely phishing or SEO spam. No scripts were extracted, but the PDF structure itself is designed to redirect users to potentially malicious URLs.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9998

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://pelibifir.ru/123?utm_term=astronomy+today+8th+edition+pdf+chapter+3 PDF link annotation
    • http://viwavidif.getenjoyment.net/formas_ser_bachiller_2020.pdfIn PDF document text
    • https://sutovuwoti.weebly.com/uploads/1/3/0/9/130968995/kemukesi_tofuwanibu_mogotof.pdfIn PDF document text
    • https://tinulesuse.weebly.com/uploads/1/3/4/6/134689832/1332237.pdfIn PDF document text
    • https://pufizemopuvagup.weebly.com/uploads/1/3/1/4/131407511/4189251.pdfIn PDF document text
    • https://nisuwifa.weebly.com/uploads/1/3/1/4/131453943/dewikijuwiva.pdfIn PDF document text
    • https://virubavu.weebly.com/uploads/1/3/4/7/134755547/a77c9cae.pdfIn PDF document text
    • http://vodabutopidaru.getenjoyment.net/add_watermark_to_in_acrobat_pro.pdfIn PDF document text
    • http://dizurexemubegog.mygamesonline.org/lewowuzonujafisobipenobev.pdfIn PDF document text
    • https://xipumizi.weebly.com/uploads/1/3/4/7/134746986/afe93ac2783d.pdfIn PDF document text
    • http://www.ascendercorp.com/In PDF document text
    • http://www.ascendercorp.com/typedesigners.htmlIn PDF document text
    • https://52431b39-7396-4b0c-bcaf-ab72d449a1bf.filesusr.com/ugd/f8cef3_61970ad88fb6451d9cd4ede7d994b540.pdf?index=trueIn PDF document text
    • https://9c8f49e5-5895-4656-bc53-c560b1a0ede3.filesusr.com/ugd/0f7a6f_fcfab4ddae304426a54719381828b217.pdf?index=trueIn PDF document text
    • https://s3.amazonaws.com/bawalidamovidud/itunes_for_windows_8._1.pdfIn PDF document text
    • https://f1fb087f-5d49-4061-aa02-230b108315d3.filesusr.com/ugd/645068_e846906b9cd04eb2ae4ea44494fae95f.pdf?index=trueIn PDF document text
    • https://s3.amazonaws.com/fofeguj/la_ruta_hacia_el_dorado_canciones.pdfIn PDF document text
    • https://dba0ca6b-c979-46b3-87c9-041648dee063.filesusr.com/ugd/6f58fb_d2a6e52a699c42429c845f51a3903221.pdf?index=trueIn PDF document text
    • http://widusop.atwebpages.com/dilumorenanu.pdfIn PDF document text
    • https://37976aa0-f55f-47d3-847a-8d185b13ebf6.filesusr.com/ugd/1d6212_46192661202d4a229e64871fd63eea28.pdf?index=trueIn PDF document text
    • https://s3.amazonaws.com/duzexefemosaxe/12978171174.pdfIn PDF document text
    • https://cbf60184-924b-4e65-abc2-244eb733ec12.filesusr.com/ugd/9a25f9_82df6dd11bf94cb28e4f7a475a858381.pdf?index=trueIn PDF document text
    • https://s3.amazonaws.com/lofese/23323607261.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_off0000cd5c.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xCD5C 5812 bytes
SHA-256: 04546fc72bc60b8048660e021b2de10bbf13b9c48282dca919c447ff53537112
font_01_sfnt_off0000e10a.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xE10A 10256 bytes
SHA-256: e16239cad721c20f3abdee35ac4af2c9ff9448aabf81e4ee1169650570ec3eae