Malicious PDF — malware analysis report

Static analysis result for SHA-256 b2810e6395e1d803…

MALICIOUS

PDF

89.6 KB Created: 2021-09-16 07:11:17 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3)
MD5: 57c0f135c749d4b40b0bb46a071b1e18 SHA-1: 017620ffde08a6e58922733524d0e997ac442b7f SHA-256: b2810e6395e1d8033ff8640b7eca57eb31ee04a3b70064bacb43dcee4bdca046
174 Risk Score

Malware Insights

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

The sample is a PDF document identified as malicious by ClamAV and an ML classifier. It contains embedded JavaScript and numerous links to external PDFs, many hosted on disposable domains, suggesting a phishing or malware distribution attempt. The PDF_RANDOM_URL_LINK heuristic indicates a high likelihood of malicious intent, likely to download a second-stage payload.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9973

Heuristics 7

  • ClamAV: Pdf.Phishing.Trojan-d2528dad23a95d95-d2528dad23a95d95-10044376-0 critical CLAMAV_DETECTION
    ClamAV detected this file as malware: Pdf.Phishing.Trojan-d2528dad23a95d95-d2528dad23a95d95-10044376-0
  • 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.
  • 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://italvaping.com/file/76456172356.pdf
    • http://www.jacenter.org/js/ckfinder/userfiles/files/vubifakak.pdf
    • http://av-jet.ru/userfiles/file/fodejowutegojosof.pdf
    • http://tongkhomica.com/upload/files/93817352011.pdf
    • http://jszl-rolls.com/filespath/files/20210906115510.pdf
    • http://media-production.net/admin/ckfinder/userfiles/files/nigibofezi.pdf
    • https://stiglic.sk/userfiles/file/komidu.pdf
    • http://extreamtuning.ru/wp-content/plugins/formcraft/file-upload/server/content/files/16137660bc9b0f---sezipateromomuwa.pdf
    • http://capitaloffice.pl/fotki/file/41277369370.pdf
    • http://topflexsports.com/uploads/33972574471.pdf
    • http://salamino.pl/userfiles/file/pikelusadijis.pdf
    • http://yibetter.com/data/files/pavusefizofeveliwo.pdf
    • https://yumasri.com/assets/ckfinder/userfiles/files/5475973347.pdf
    • http://ambulatorioveterinariobubiniregini.eu/userfiles/files/64680237892.pdf
    • https://seikai.jp/free_images/files/kobezezonozutok.pdf
    • http://thepokeluau.com/uploads/files/pimozebebeb.pdf
    • https://www.alertgy.com/wp-content/plugins/super-forms/uploads/php/files/5eea505ef184770e066c241cef83c081/bepefokozeparu.pdf
    • http://ettorebelfioreliutaio.it/userfiles/files/21902283782.pdf
    • http://hp-cnc.de/uploads/files/7334339092.pdf
    • http://studiobardinisrl.com/userfiles/files/34243702186.pdf
    • http://www.gulbaharsigorta.com/contentData/file/62379562936.pdf
    • https://electrodomesticaruano.com/images/ckfinder/files/muwikibasuzav.pdf
    • http://badischer-kunstverein.de/ckfinder/userfiles/files/nesebanu.pdf
    • https://egokituz.eus/files/galeria/files/tuzixopamomip.pdf
    • https://saint-florentin.charcutier-traiteur.fr/ckfinder/userfiles/files/47225380905.pdf
    • https://feedproxy.google.com/~r/skout/mBVl/~3/ngfLrbzwjls/uplcv?utm_term=kingsman+full+movie+online+watch
    • http://www.w3.org/1999/02/22-rdf-syntax-ns#
    • http://purl.org/dc/elements/1.1/
    • http://ns.adobe.com/pdf/1.3/
    • http://ns.adobe.com/xap/1.0/
    • http://ns.adobe.com/xap/1.0/mm/
    • http://ns.adobe.com/xap/1.0/rights/
    • http://dejavu.sourceforge.net
    • http://dejavu.sourceforge.net/wiki/index.php/License

Extracted artifacts 3

Files carved from inside the sample during analysis.

FilenameKindSourceSize
font_00_sfnt_off0000f9d5.bin
9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
pdf-font-stream PDF embedded font (sfnt) at offset 0xF9D5 16792 bytes
font_01_sfnt_off000111ec.bin
9bef425076e1b15732efcedeccc76292c3dee84ac00c9fb23a1c986c9b7adee9
pdf-font-stream PDF embedded font (sfnt) at offset 0x111EC 10924 bytes
font_02_sfnt_off00012b1f.bin
3d086a81195141998daf8e43605a46fa0afac0cf75ef9614217671b10f864dd8
pdf-font-stream PDF embedded font (sfnt) at offset 0x12B1F 17596 bytes