Malicious PDF — malware analysis report

Static analysis result for SHA-256 2435392e56eca1f6…

MALICIOUS

PDF

95.3 KB Created: 2021-09-08 13:58:57 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-10-16
MD5: 3eb3f4cf4a562043467649a8df8187e1 SHA-1: 51a194f87973ef0a5a5310ae986843727c02554c SHA-256: 2435392e56eca1f6396018c945fb0f124a4f85b7ad04bd6266e00db84bd5b203
166 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment

The PDF contains numerous external links, many pointing to disposable hosting, and is flagged as a link farm. The ML classifier and ClamAV detection strongly indicate malicious intent, likely for phishing or distributing further malware. Although no scripts were explicitly extracted, the PDF structure and URL patterns are indicative of malicious activity.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9820

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
  • PDF link to algorithmically-generated URL high PDF_RANDOM_URL_LINK
    PDF contains a clickable HTTP(S) link whose host looks algorithmically generated (pronounceable-random labels) and whose path/query carries a long high-entropy token. This is the randomized-redirector pattern of malspam phishing lures — the visible document is only a prompt — not a PDF parser vulnerability.
  • 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://pixomot.ru/uplcv?utm_term=structure+elucidation+of+camphor+pdf PDF link annotation
    • http://www.hausbaumesse.at/ckfinder/userfiles/files/59747450812.pdfIn PDF document text
    • https://serwisnawigacji.pl/userfiles/file/juvivegudu.pdfIn PDF document text
    • https://visualarchive.bg/files/ferituromadatu.pdfIn PDF document text
    • http://52963566.com/upload/file/202109030704061798.pdfIn PDF document text
    • http://staropolski.net/Upload/file/99934403553.pdfIn PDF document text
    • http://ewhamd.net/upFiles/ckeditor/files/45428942092.pdfIn PDF document text
    • http://carraracucinecomponibilitrapani.it/userfiles/files/2875300514.pdfIn PDF document text
    • https://karpzbeldowa.pl/uploads/userfiles/files/japoder.pdfIn PDF document text
    • http://embody.box8websites.com/ckfinder/userfiles/files/wakafunazawesese.pdfIn PDF document text
    • https://parklanehotel.asia/userfiles/file/xifijepalok.pdfIn PDF document text
    • http://shengyaweb.com/uploadfile/file/2021090702200695.pdfIn PDF document text
    • http://coeb.eu/userfiles/files/sukapedutowimoravijiki.pdfIn PDF document text
    • https://fiscalonline.ro/app/webroot/files/userfiles/files/dutiz.pdfIn PDF document text
    • http://nachhilfeschule.havonix.com/ckfinder/userfiles/files/vuwinodiw.pdfIn PDF document text
    • http://axiomestates.com/userfiles/file/xixupazodivedaparur.pdfIn PDF document text
    • http://thanhcongtechtra.com/upload/files/dutasufubala.pdfIn PDF document text
    • http://www.scmphotography.co.uk/wp-content/plugins/formcraft/file-upload/server/content/files/1612f91f95774b---87666197172.pdfIn PDF document text
    • http://china-miyaco.com/img/file/202196235438.pdfIn PDF document text
    • http://greentreeprep.com/cote_dor_import/admin/ckfinder/userfiles/files/39886754490.pdfIn PDF document text
    • http://xedaphcm.com/luutru/files/guwelizabuda.pdfIn PDF document text
    • http://abwhopewell.com/uploads/files/koxip.pdfIn PDF document text
    • https://ncfouting.com/wp-content/plugins/formcraft/file-upload/server/content/files/16137f9170aa7a---61993019606.pdfIn PDF document text
    • http://ecohort.com/userfiles/files/gapapuzebalevukisuxedekat.pdfIn PDF document text
    • http://auto-rad.pl/userfiles/file/55088236308.pdfIn PDF document text
    • http://ourdesign.hk/ckfinder/userfiles/files/27386904238.pdfIn PDF document text
    • https://www.thc.gda.pl/ckfinder/userfiles/files/28696425929.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_off0001072d.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x1072D 20688 bytes
SHA-256: d9444c78028533786abae46194b811fe27643b618db6703d157436516d74ddfb
font_01_sfnt_off00013e3f.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x13E3F 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
font_02_sfnt_off00015656.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x15656 10892 bytes
SHA-256: d05c295659c4fada73ce689e49408c25c80cc282cf97e0b147c559d79542a1d7