Malicious PDF — malware analysis report

Static analysis result for SHA-256 f28eac3f5a159afd…

MALICIOUS

PDF

93.8 KB Created: 2021-09-21 23:53:13 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3)
MD5: 21df105f338ddb736dbc6062b6f945ea SHA-1: 33bc6278066d2b02063ee0f032cd40f97cc87a55 SHA-256: f28eac3f5a159afd45f776b304249bd4dbce1ce6e9a2b5bd374948c5f7c06c7f
156 Risk Score

Malware Insights

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

The PDF contains a large number of links, many of which point to compromised CMS upload storage or disposable hosting, indicating a link farm designed to distribute malicious content. The ClamAV detection and ML classifier strongly suggest this PDF is malicious, likely serving as a lure for phishing or to exploit vulnerabilities. No scripts were extracted from this sample.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9982

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 farm points to compromised-WordPress upload storage medium PDF_COMPROMISED_CMS_UPLOAD_LINK_FARM
    PDF contains multiple clickable links, across many distinct hosts, whose targets are random-slug files parked in the upload directories of vulnerable WordPress form plugins (FormCraft, Super Forms). This is the hallmark of the 'free document/template' SEO phishing PDF family, which ranks for search queries and routes users into payload/redirect chains hosted on compromised sites. The PDF itself carries no exploit — the risk is the linked destinations.
  • 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://eurogeographyjournal.eu/admin/fckfiles/file/jurevepamalejamerajojo.pdf
    • http://www.cpiequipos.com/assets/images/user_files/files/41608137691.pdf
    • http://dzbnf.com/upload/file///36591718099.pdf
    • http://ahchala.com/img/file/tuwotibunezinarizomi.pdf
    • https://www.hungryalex.com/wp-content/plugins/super-forms/uploads/php/files/24605ddd9663f2e317265273ede2b7fb/43042233400.pdf
    • http://grapes4u.ca/sites/all/sites/grapes4u.ca/files/60966512907.pdf
    • https://kvartira-zalog.ru/wp-content/plugins/super-forms/uploads/php/files/b1d8bbf3a060262a58df0198e4ca3c8c/18528023602.pdf
    • http://szentistvanpatika.hu/upload/file/nuwavafawixoxogo.pdf
    • https://plumcourse.com/wp-content/plugins/super-forms/uploads/php/files/dbc2753125241006f2fb53670df761b4/51693096910.pdf
    • https://weeb.nu/userfiles/file/34570610943.pdf
    • https://ourcampuswindow.com/ckfinder/userfiles/files/mukuraxolowuri.pdf
    • http://recamonde.com.br/wp-content/plugins/formcraft/file-upload/server/content/files/1613eccbd05c83---18266242724.pdf
    • https://maria-galland.ru/files/file/sisovavumagumipinaxoralu.pdf
    • http://andrenickels.de/ckfinder/userfiles/files/59453387379.pdf
    • https://lordoptika.hu/files/files/77546359615.pdf
    • https://kalatranslation.co.uk/wp-content/plugins/super-forms/uploads/php/files/lsuqi9fbmkmla881o98hv3349r/tovowovami.pdf
    • https://iphonerepairservice.nl/app/webroot/files/userfiles/files/zafozikupubefafimab.pdf
    • http://ds-dq.com/uploadfile/1632143407.pdf
    • http://www.alliance-bio.com/user_data/editor/ckfinder/core/connector/php/upload/files/girodiwoperagerisuvi.pdf
    • https://brs.jo/userfiles/files/25708626517.pdf
    • https://inprovitecuador.com/ckfinder/userfiles/files/fijawupo.pdf
    • https://feedproxy.google.com/~r/skout/mBVl/~3/6naE_Nh8_CY/uplcv?utm_term=fortnite+chapter+2+season+6+free+skins
    • 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_off00010b9a.bin
1cdb30bfcd6b13ed417599557814922b408c98ae8748ea3797e538a67566261e
pdf-font-stream PDF embedded font (sfnt) at offset 0x10B9A 17308 bytes
font_01_sfnt_off00013830.bin
9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
pdf-font-stream PDF embedded font (sfnt) at offset 0x13830 16792 bytes
font_02_sfnt_off00015047.bin
85097fef6a60ecde6f71951d829868d1694ae87b7f38b39ca28bc1acc54e5761
pdf-font-stream PDF embedded font (sfnt) at offset 0x15047 10888 bytes