Malicious PDF — malware analysis report

Static analysis result for SHA-256 d53798876c0e5b99…

MALICIOUS

PDF

79.6 KB Created: 2021-06-03 16:10:27 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 4.8.7) First seen: 2021-09-25
MD5: 2b0218f4be63aa33fe33396137c96782 SHA-1: e8a798bb9c6ce5a49227537c2252f80526ae26c7 SHA-256: d53798876c0e5b993b08e6921d2f9a456e5b44baa612baf2511de08a55d983b4
186 Risk Score

Malware Insights

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

This PDF document was flagged as malicious by ClamAV and an ML classifier. The file embeds a large number of external links characteristic of an SEO link farm. Specific URLs and indicators for this sample are listed in the indicators section.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9993

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=bootstrap+form-+control+max+width PDF link annotation
    • https://cdn-cms.f-static.net/uploads/4502268/normal_60698537129c9.pdfIn PDF document text
    • https://cdn-cms.f-static.net/uploads/4402504/normal_604de29a9bd7a.pdfIn PDF document text
    • https://static.s123-cdn-static.com/uploads/4369776/normal_60016599144d5.pdfIn PDF document text
    • https://cdn-cms.f-static.net/uploads/4427267/normal_6066fedb9654f.pdfIn PDF document text
    • https://javesobasi.weebly.com/uploads/1/3/4/7/134736097/sozofegulogu.pdfIn PDF document text
    • https://getomipo.weebly.com/uploads/1/3/4/4/134403721/1545625.pdfIn PDF document text
    • https://cdn-cms.f-static.net/uploads/4375704/normal_60260db8353a2.pdfIn PDF document text
    • https://xudepafuvinuk.weebly.com/uploads/1/3/0/9/130969511/5333359.pdfIn PDF document text
    • https://vopoxeja.weebly.com/uploads/1/3/5/3/135346001/2613923.pdfIn PDF document text
    • https://nepexinis.weebly.com/uploads/1/3/1/4/131438592/kotiguraka.pdfIn PDF document text
    • https://bagesasadav.weebly.com/uploads/1/3/4/3/134383367/tawaxut.pdfIn PDF document text
    • https://zireguxeked.weebly.com/uploads/1/3/4/8/134863403/jefavef_vipipizuvotevuf_fasexawotazuti_viximolebotalo.pdfIn PDF document text
    • https://static.s123-cdn-static-d.com/uploads/4365619/normal_60b1a25db19ba.pdfIn PDF document text
    • https://masezinonorokun.weebly.com/uploads/1/3/4/6/134685416/nevuvivujom_besuxikulelogur.pdfIn PDF document text
    • https://cdn-cms.f-static.net/uploads/4459328/normal_600fd7f042186.pdfIn PDF document text
    • http://www.ascendercorp.com/In PDF document text
    • http://www.ascendercorp.com/typedesigners.htmlIn PDF document text
    • http://ridelox.pbworks.com/w/file/fetch/144467313/najadarisogukaz.pdfIn PDF document text
    • http://sipibujewadu.pbworks.com/f/rangers_of_shadow_deep_vf.pdfIn PDF document text
    • http://ropotupi.pbworks.com/w/file/fetch/144562362/how_do_i_reset_my_onkyo_receiver_tx_sr373.pdfIn PDF document text
    • http://xifatarege.pbworks.com/f/dead_suns.pdfIn PDF document text
    • http://kizisoj.pbworks.com/w/file/fetch/144519843/fofinurevef.pdfIn PDF document text
    • http://maxasol.pbworks.com/f/voxixabuponufinotab.pdfIn PDF document text
    • http://jutifakukap.pbworks.com/f/how_to_calculate_volume_of_irregular_trapezoid.pdfIn PDF document text
    • http://vakerul.pbworks.com/f/96977336044.pdfIn PDF document text
    • http://jetipufagi.pbworks.com/f/what_is_the_key_difference_between_aerobic_and_anaerobic_respiration_in_prokaryotes.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_off0000f805.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xF805 5636 bytes
SHA-256: de9d61a1a0421265cda100df069dad092ddcb038dc3acc033e716589a728267f
font_01_sfnt_off00010b2a.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x10B2A 10996 bytes
SHA-256: 6bff69a0b597f4b9bc51fcef2bd5482827703dd797f08ad3a16bfa8234bee7de