Malicious PDF — malware analysis report

Static analysis result for SHA-256 13a795392518639d…

MALICIOUS

PDF

87.8 KB Created: 2021-07-18 17:00:44 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3)
MD5: 8e4842d938ab3fcebe9e8f745ccbe041 SHA-1: 7bf5c31c4a9dffcb4517d0afa0172472f80d11ba SHA-256: 13a795392518639dde51a600497753dc08c0521fc9bc0b2900fe20f419226c80
156 Risk Score

Malware Insights

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

The PDF contains numerous links pointing to various domains, many of which are identified as disposable hosting or compromised CMS uploads. The ML classifier and ClamAV detection strongly indicate malicious intent, likely related to phishing or distributing further malware. The document body is heavily obfuscated and unreadable, providing no direct clues to its purpose beyond the heuristic findings.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9942

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://cupta.org/userfiles/files/20210527005906.pdf
    • https://grand-forge.ru/wp-content/plugins/super-forms/uploads/php/files/70dfe63c20fc4ad86d21d5e2c4279c4c/37888663436.pdf
    • http://infrabud.eu/fckpliki/file/95437871421.pdf
    • http://europeanprofservices.com/wp-content/plugins/formcraft/file-upload/server/content/files/160bf1c103fc8a---zamidomasurotepe.pdf
    • https://formapolis.it/wp-content/plugins/super-forms/uploads/php/files/8bc8c6eb0fbc057b787bf22a9f72e8e4/xabakitelizugipuzifi.pdf
    • http://ozkayalartrans.com/userfiles/file/gososuluwemomopemamanune.pdf
    • https://accuratesearch.com/userfiles/file/venogu.pdf
    • https://flylights.pl/wp-content/plugins/super-forms/uploads/php/files/d7j0k0mrnu4r2dkenbfbspisvf/retaza.pdf
    • http://www.ibadirect.com/wp-content/plugins/formcraft/file-upload/server/content/files/160c9905735866---tomafafaj.pdf
    • https://tehnol.ru/wp-content/plugins/formcraft/file-upload/server/content/files/1606fc4efc51bb---forovatowonanijevosozif.pdf
    • http://kwik-it.ru/wp-content/plugins/formcraft/file-upload/server/content/files/1607e822baae09---vugagebevivu.pdf
    • http://sip7.online/wp-content/plugins/super-forms/uploads/php/files/e34fe6bac684e72dce1fd263b65a1260/zesewafobebibegulat.pdf
    • https://kamber.dk/wp-content/plugins/super-forms/uploads/php/files/62c53f1a1f7d999cf297aeb9b4c50a9c/zezanir.pdf
    • http://ipvoicenj.com/wp-content/plugins/formcraft/file-upload/server/content/files/160cb76f62cb9c---rejadoluraxutefu.pdf
    • https://avis-medical.ma/wp-content/plugins/super-forms/uploads/php/files/c5a9c1c1e8d7be5a5f8a6374459c9938/60703494398.pdf
    • https://singaporeroadshow.com/wp-content/plugins/super-forms/uploads/php/files/113f46a56b8f475ee278029c5fb5b8c4/33423118314.pdf
    • http://www.1000ena.com/wp-content/plugins/formcraft/file-upload/server/content/files/160825c6d49ade---68738187338.pdf
    • http://aihyang.com/userfiles/file/mopotukurerexa.pdf
    • http://pulsrmedia.com/wp-content/plugins/formcraft/file-upload/server/content/files/160c8b34f553f1---6146952633.pdf
    • http://cedule-plachty.cz/files/file/63206491160.pdf
    • https://moveo-sport.pl/userfiles/file/7576532723.pdf
    • https://funkydrop.shop/wp-content/plugins/super-forms/uploads/php/files/470ea2dc71729ade33885699b4629d64/dupixivuxunuwelutes.pdf
    • https://alismobile.co.uk/wp-content/plugins/super-forms/uploads/php/files/b35b84b4e0238967f75620800ad757fb/dafezafozalepiduwetibid.pdf
    • https://wacee.net/wp-content/plugins/formcraft/file-upload/server/content/files/160d3bde29b2c1---sarivibanumonizojov.pdf
    • http://eurogeographyjournal.eu/admin/fckfiles/file/zexosadulu.pdf
    • https://feedproxy.google.com/~r/skout/mBVl/~3/6naE_Nh8_CY/uplcv?utm_term=celebrity+crossword+puzzles+answers
    • 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_off0000f2dd.bin
9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
pdf-font-stream PDF embedded font (sfnt) at offset 0xF2DD 16792 bytes
font_01_sfnt_off00010af4.bin
bde79db26a5b5cff4542f9ee93b3abcf141de810ed4f0bf1d79a93fb33b34ddd
pdf-font-stream PDF embedded font (sfnt) at offset 0x10AF4 11040 bytes
font_02_sfnt_off000124ad.bin
3391097578b1cd0f160cf94872c5b0306659ab501e9fe977465b22b0cddb9eee
pdf-font-stream PDF embedded font (sfnt) at offset 0x124AD 17272 bytes