Malicious PDF — malware analysis report

Static analysis result for SHA-256 bc4135d20ad39204…

MALICIOUS

PDF

76.8 KB Created: 2021-06-04 15:27:09 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 4.8.7) First seen: 2021-09-23
MD5: 9b07bc0d364a271bef06022e74bef2be SHA-1: 72c6d1772279b46e619c305712c5398ff30610ea SHA-256: bc4135d20ad392048c388741de11f599ed3f0e9f553ab43e83d5333924e76c3f
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 0.9998

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://cructi.ru/pbw?utm_term=cuantos+son+2+3%252F4+pulgadas+en+centimetros PDF link annotation
    • https://tajifajedu.weebly.com/uploads/1/3/1/6/131637014/judatilifefopiw_marojefot.pdfIn PDF document text
    • https://nizitorewazoxi.weebly.com/uploads/1/3/4/7/134704220/dazerasegone_dabulokigiv_dekub_varodifi.pdfIn PDF document text
    • https://cdn-cms.f-static.net/uploads/4474470/normal_5fd7748d6962d.pdfIn PDF document text
    • https://gazulaloruvuv.weebly.com/uploads/1/3/4/6/134693071/dilulibag.pdfIn PDF document text
    • https://nuzukozifazo.weebly.com/uploads/1/3/2/6/132682871/8775373.pdfIn PDF document text
    • https://cdn-cms.f-static.net/uploads/4453729/normal_600dd0a3c6659.pdfIn PDF document text
    • https://static.s123-cdn-static.com/uploads/4489725/normal_5ff1b64af23d7.pdfIn PDF document text
    • https://luradubesi.weebly.com/uploads/1/3/4/4/134486829/diduxepis.pdfIn PDF document text
    • https://sarutofujatazix.weebly.com/uploads/1/3/4/5/134584212/4823030.pdfIn PDF document text
    • https://cdn-cms.f-static.net/uploads/4404497/normal_605207e97e22e.pdfIn PDF document text
    • https://dafuravo.weebly.com/uploads/1/3/4/8/134862971/73e63f86eceeb43.pdfIn PDF document text
    • https://fuxomiluzixoxam.weebly.com/uploads/1/3/4/5/134594746/zoxapavajelupe.pdfIn PDF document text
    • https://fimusaruto.weebly.com/uploads/1/3/4/4/134472122/jakezupatubedijinul.pdfIn PDF document text
    • http://www.ascendercorp.com/In PDF document text
    • http://www.ascendercorp.com/typedesigners.htmlIn PDF document text
    • http://pefumugat.pbworks.com/w/file/fetch/144592794/break_even_point_analysis_example_problems.pdfIn PDF document text
    • http://kigemulu.pbworks.com/w/file/fetch/144550518/batman_arkham_knight_invincibility_cheat_ps4.pdfIn PDF document text
    • http://risuxujuvu.pbworks.com/w/file/fetch/144512751/spongebob_squarepants_full_episodes.pdfIn PDF document text
    • https://uploads.strikinglycdn.com/files/660cd997-f2dd-4357-afcf-9076f0fea90f/56235635177.pdfIn PDF document text
    • https://uploads.strikinglycdn.com/files/e0d75dbc-cf24-49d3-ad63-0c9007842f56/the_signalman_summary_shmoop.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
    • http://dejavu.sourceforge.netIn PDF document text
    • http://dejavu.sourceforge.net/wiki/index.php/LicenseIn PDF document text

Extracted artifacts 3

Files carved from inside the sample during analysis.

FilenameKindSourceSize
font_00_sfnt_off0000d465.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xD465 5720 bytes
SHA-256: 4b291f8ce602636ec5746824d2b8a3b9e42c0d87989252f101007f7b3b38b088
font_01_sfnt_off0000e7d6.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xE7D6 12412 bytes
SHA-256: 0d0544df3b4b72d9fc1f71f63f31c953fc7d499f8f7d00f652241642e8769ece
font_02_sfnt_off00011096.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x11096 16108 bytes
SHA-256: f95089c45a512c255e04fff4eb86a50bbe210c04adcc9bc093880eb7f83978af