Malicious PDF — malware analysis report

Static analysis result for SHA-256 9c2391cd10abe3bf…

MALICIOUS

PDF

70.4 KB Created: 2021-09-11 23:46:01 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-10-16
MD5: 9a3bbaf9ebdb9942f86f3d44971e820e SHA-1: 38694767512ef61294a7d1a2c1bd5ae81c2a89d1 SHA-256: 9c2391cd10abe3bf1893026f02e68d68392a1906cabcdc045da4b37ef164f4d2
134 Risk Score

Malware Insights

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

This PDF file was flagged as malicious by ClamAV and an ML classifier, indicating a high likelihood of malicious intent. The embedded JavaScript stream and numerous external URIs, particularly the one pointing to 'inwebjor.ru' with a 'free vpn' term, suggest a phishing or malware distribution lure. The document's structure as a link farm on disposable hosting further supports a malicious purpose, likely to redirect users to exploit kits or download further malicious payloads.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9956

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 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.
  • Embedded JS stream low PDF_JS
    PDF references a /JS stream. Generic JavaScript is common in benign forms; specific dangerous APIs are scored by separate rules.
  • 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://inwebjor.ru/uplcv?utm_term=free+vpn+power+vpn+download PDF link annotation
    • http://zamdq.com/filespath/files/20210903055427.pdfIn PDF document text
    • http://thevisionkharj.com/userfiles/files/47167571382.pdfIn PDF document text
    • http://henzefashion.com/userfiles/file/bosajuvawikomevom.pdfIn PDF document text
    • https://miamivanservice.net/wp-content/plugins/formcraft/file-upload/server/content/files/1612f48f4b917c---83543410538.pdfIn PDF document text
    • http://microcement.ua/userfiles/file/ripusatam.pdfIn PDF document text
    • https://takipcisec.com/calisma2/files/uploads/buxijogovebagase.pdfIn PDF document text
    • http://rtm-plus.ru/ckfinder/userfiles/files/3464643943.pdfIn PDF document text
    • https://derya.afmiletisimajansi.info/resimler/files/78378962263.pdfIn PDF document text
    • http://manvilastrust-org.bvirani.com/ckfinder/userfiles/files/ponoxatisinikipe.pdfIn PDF document text
    • https://impeka.lt/components/com_mijoshop/opencart/image/data/files/mufasu.pdfIn PDF document text
    • http://fortwashington.abwingsmd.com/uploads/files/22899679909.pdfIn PDF document text
    • https://textosolutionslinguistiques.com/upload/editor/file/28776918687.pdfIn PDF document text
    • http://domexpo.ru/up/file/10064910463.pdfIn PDF document text
    • http://vasset.bg/userfiles/file/68644010497.pdfIn PDF document text
    • https://chingchia.com/uploads/files/202109051807039118.pdfIn PDF document text
    • http://hart-metale.pl/gimnazjum/userfiles/file/67989876774.pdfIn PDF document text
    • https://silatur.com/js/ckfinder/userfiles/files/17700985685.pdfIn PDF document text
    • http://nhagiatxanh.com/public/default/ckeditor/files/vulirumagumumurisabo.pdfIn PDF document text
    • https://magicdiscoradio.hu/userfiles/file/47575774001.pdfIn PDF document text
    • http://kompletucetnictvi.cz/files/file/86484150099.pdfIn PDF document text
    • http://unicorn-furnitures.com/d/files/2263985752.pdfIn PDF document text
    • http://computer-rudolstadt.de/upload/file/4437924055.pdfIn PDF document text
    • http://synhbio.com/upload/files/52009891127.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://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_off0000b39f.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xB39F 16276 bytes
SHA-256: 2f0278464bf952bc42f0127ef209b39a40ddd166671158179492a74ff3ab8d19
font_01_sfnt_off0000ddb2.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xDDB2 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
font_02_sfnt_off0000f5c9.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xF5C9 10156 bytes
SHA-256: b8a23f3e8175b7678b7229e3829fc82bb8cdd59c3a41ffc9885894d4b4819c4a