Malicious PDF — malware analysis report

Static analysis result for SHA-256 085572053bd97108…

MALICIOUS

PDF

80.5 KB Created: 2021-09-10 15:59:24 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-10-14
MD5: b93521851943baa7912ff230b772cadd SHA-1: e09a92ad6cd19e7064b7d5f5d8c9669814d8bb5b SHA-256: 085572053bd971080913aad67648833b025ac973b3b21d6757095a8054920eff
166 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment T1203 Exploitation for Client Execution

The PDF file was flagged by a ML classifier and ClamAV as malicious, with heuristics indicating it's a phishing attempt and uses social engineering to prompt user interaction. The SE_CLICKFIX heuristic specifically mentions instructions to press Win+R or paste a command, which is a known technique to bypass macro restrictions and execute arbitrary commands. While no scripts were directly extracted, the nature of the attack suggests it aims to download and execute a second-stage payload.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9960

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
  • ClickFix social engineering attack high SE_CLICKFIX
    Document instructs the user to press Win+R or paste a command into a terminal — consistent with ClickFix attacks that bypass macro restrictions by tricking users into running malicious commands directly
  • 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 http://thucphamchucnangmy.vn/uploads/files/50541538516.pdf In PDF document text
    • http://erex.hu/upload/file/7266557982.pdfIn PDF document text
    • http://infinity8talents.com/userfiles/file/pipadegavudupitin.pdfIn PDF document text
    • https://delta-relay.be/userfiles/file/bodiz.pdfIn PDF document text
    • http://spokoino.ru/i/upload/files/70906066492.pdfIn PDF document text
    • http://dragonspond.com/uploads/files/6755033167.pdfIn PDF document text
    • http://imobilestore.de/userfiles/file/15364118148.pdfIn PDF document text
    • http://dailyliving.nl/ckfinder/userfiles/files/boruvuzomorifopiv.pdfIn PDF document text
    • http://wamer.org/userfiles/file/xabirepukakorajatumovizup.pdfIn PDF document text
    • http://www.pranabkumar.com/fckimages/file/demesizexeweluk.pdfIn PDF document text
    • https://rivieresoceanie.com/ckfinder/userfiles/files/92220500465.pdfIn PDF document text
    • http://maulich.vn/attachment/files/valiwomidireserurozivexip.pdfIn PDF document text
    • https://ahha.az/userfiles/file/lepetejedud.pdfIn PDF document text
    • http://caythuocdangian.net/images/files/pikiwuv.pdfIn PDF document text
    • http://www.kissdocs.com.au/wp-content/plugins/formcraft/file-upload/server/content/files/16138d15bb2c13---96765565446.pdfIn PDF document text
    • http://picassogift.com/Uploadfiles/files/1375623139.pdfIn PDF document text
    • http://victoryelectricalsupply.com/ckfinder/userfiles/files/90820730683.pdfIn PDF document text
    • http://www.infranetltd.com/wp-content/plugins/formcraft/file-upload/server/content/files/1613020b2a099e---82818868053.pdfIn PDF document text
    • http://megalabsrl.it/userfiles/files/pijimavafupubereroj.pdfIn PDF document text
    • http://ychnjl.net/userfiles/files/merenibavanosenetupowo.pdfIn PDF document text
    • http://www.cda.org.hk/ckfinder/userfiles/files/satamar.pdfIn PDF document text
    • http://oprandi.it/userfiles/files/noxitisefijugisujivofuwoj.pdfIn PDF document text
    • http://ricettebiagi.it/uploads/assets/file/xaviruwojalonew.pdfIn PDF document text
    • https://feedproxy.google.com/~r/skout/mBVl/~3/3vuEKuznOb8/uplcv?utm_term=cara+merubah+icon+aplikasi+androidPDF link annotation
    • 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://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_off0000d505.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xD505 17944 bytes
SHA-256: 19da89784e731426df4f31626fb30701d4aeb5dcf937c4b9986939a1cdaa0589
font_01_sfnt_off00010387.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x10387 11044 bytes
SHA-256: 8a3d39bfc5c90ec504197d2b1716ba0b34cce1af483364930f739d41129f48bb
font_02_sfnt_off00011cc8.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x11CC8 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1