Malicious PDF — malware analysis report

Static analysis result for SHA-256 837ead3ed624179b…

MALICIOUS

PDF

81.6 KB Created: 2021-10-05 02:51:53 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-11-25
MD5: c6277a254c3b855e8b395745c1ba5cf3 SHA-1: 555f83e7464ced22d13d997748b2c5f33f7ee294 SHA-256: 837ead3ed624179baf941ac45f0aee777d23eeb6713ec1f2b8adf7d5472956bc
126 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment

The PDF contains numerous embedded URLs, many of which point to disposable domains and are structured as link farms, indicating a phishing or malware distribution attempt. The ML classifier and ClamAV detection strongly suggest malicious intent. While no scripts were directly extracted, the PDF structure and embedded URIs are indicative of a malicious document designed to redirect users to potentially harmful content.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9917

Heuristics 5

  • 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.
  • 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://ketchas.ru/uplcv?utm_term=the+thing+about+jellyfish+by+ali+benjamin PDF link annotation
    • https://seas2010.cienciaevida.pt/site/upload/file/benoriludemilos.pdfIn PDF document text
    • http://ilink.pl/userfiles/file/43448641998.pdfIn PDF document text
    • http://hasicimosnov.cz/foto/Image/file/dadinudobosetaletumas.pdfIn PDF document text
    • http://golfproradost.cz/webpagebuilder/ckfinder/userfiles/files/25320466718.pdfIn PDF document text
    • http://streathamtaxi.com/survey/userfiles/files/53166957280.pdfIn PDF document text
    • https://shriramsteels.in/public/ckfinder/userfiles/files/7211527387.pdfIn PDF document text
    • http://slovoveri.org/userfiles/famudumepezifaligosulawa.pdfIn PDF document text
    • http://www.feniuniversity.edu.bd/app/webroot/ckfinder/userfiles/files/juxatuwazoze.pdfIn PDF document text
    • https://www.highettmetal.com.au/application/third_party/ckfinder/userfiles/files/guvuresisiwatanurave.pdfIn PDF document text
    • http://leylasuren.com/images/userfiles/imagefile/22437302472.pdfIn PDF document text
    • https://healthtecindia.com/userfiles/file/1193482237.pdfIn PDF document text
    • https://dorfadvertising.com/ckfinder/userfiles/files/jajologa.pdfIn PDF document text
    • http://aviatechinform.ru/sadm_files/4435830575.pdfIn PDF document text
    • http://reklama-kemerovo.ru/files/files/kudajudejegodivolizuxid.pdfIn PDF document text
    • https://songiadahoaian.com/upload/ck/files/zazakofanotujadabomena.pdfIn PDF document text
    • http://epoptavky.com/is/images/FCKeditor/File/dubex.pdfIn PDF document text
    • http://gps-ambroisie.com/ressource/site-image/files/59909172536.pdfIn PDF document text
    • http://findmecakes.com/userfiles/files/wadesopadarixejasinoza.pdfIn PDF document text
    • https://patc.fr/imagesfile/56306900844.pdfIn PDF document text
    • http://1mosref.ru/ckfinder/userfiles/files/83587097049.pdfIn PDF document text
    • http://stopasbestos.ca/wp-content/plugins/formcraft/file-upload/server/content/files/1615317499a0ba---rugikabiponuz.pdfIn PDF document text
    • http://remobudostol.pl/pliki/dapusilidinapowamurav.pdfIn PDF document text
    • https://akproauto.com/nbloom/fckuploads/file/81123069798.pdfIn PDF document text
    • https://www.kadeavenue.com/wp-content/plugins/super-forms/uploads/php/files/c8a7186fba84e459f7f0b8552a1110b2/pemuxifujizuni.pdfIn PDF document text
    • http://www.astmalek.cz/obrazky/file/lubufojadogalo.pdfIn PDF document text
    • https://maisonfamillesrimouski.com/scripts/php/xenocode/lib/ckfinder/userfiles/files/totizufojutukexamuwukepob.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_off0000d854.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xD854 11008 bytes
SHA-256: e9bfdcb8f048814b06477c37da8362a09e832432d9b61c1354695a461b648259
font_01_sfnt_off0000f1bc.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xF1BC 17728 bytes
SHA-256: ed4e83424086d716a1b6a497a06bb4dda9705f59bbdc51287eb7939183de8e1e
font_02_sfnt_off00012055.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x12055 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1