Malicious PDF — malware analysis report

Static analysis result for SHA-256 c9104b436e6c6da9…

MALICIOUS

PDF

81.6 KB Created: 2021-06-25 15:02:18 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3)
MD5: 17ac2d6ae622069a991954e5c811062c SHA-1: a290b67238be630b348c88b3fc5f31a2aa14dfab SHA-256: c9104b436e6c6da91a2bd01fe00df5f7ea29f3f374bf34bf0df1ef3202e90ee7
156 Risk Score

Malware Insights

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

The PDF contains a link farm pointing to numerous compromised WordPress sites and disposable hosting, indicating a phishing or malware distribution attempt. The ML classifier and ClamAV detection strongly suggest malicious intent. The document body is heavily obfuscated and appears to be non-readable content, further supporting the malicious nature of the file.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9994

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 https://doitsolutions.co/wp-content/plugins/super-forms/uploads/php/files/7d5b9d7e6c5bb485c456ed4f8c6a650d/gemokifobojoruvubadogese.pdf
    • https://radmangroup-ye.com/rgfiles/file/57695909504.pdf
    • http://studiofapas.it/userfiles/files/34828596716.pdf
    • https://tehnol.ru/wp-content/plugins/formcraft/file-upload/server/content/files/1609dd3ecececa---65409648611.pdf
    • http://randoquad72.fr/userfiles/file/63638149595.pdf
    • http://opalbiosciences.com/wp-content/plugins/formcraft/file-upload/server/content/files/160bd6d5254ccb---wiliselakojerode.pdf
    • http://saptpadi.com/files/file/kerupiwumejatozonirizir.pdf
    • http://thedewakohchang.com/image/upload/File/8333948865.pdf
    • http://xperion.hu/wp-content/plugins/super-forms/uploads/php/files/62a5eba23ffd755c94aa3b921a9e20df/41004188688.pdf
    • https://www.bountyvacation.com/wp-content/plugins/formcraft/file-upload/server/content/files/160bcc2f59340f---13112422962.pdf
    • http://elmiraclassiccountry.com/wp-content/plugins/super-forms/uploads/php/files/0o79f891dh2oupm8falmq45r27/49297653528.pdf
    • https://retentionstudentexperience.com/wp-content/plugins/formcraft/file-upload/server/content/files/160d36865a2330---fiwemuxezuxupegipedurixen.pdf
    • http://mlight.cz/archiv/file/pomedoxabixemovujufo.pdf
    • http://tavernadelsnoguers.com/wp-content/plugins/super-forms/uploads/php/files/a0e2f233bdd526229ef8548a30f54764/71914780551.pdf
    • https://rjiminfra.com/wp-content/plugins/super-forms/uploads/php/files/5ab3b80cdcd69a5fd94442dcd401d2fd/binuwonosap.pdf
    • http://vincityhomes.vn/wp-content/plugins/super-forms/uploads/php/files/c4f52dilhpn32po8kduvtmn697/8794628616.pdf
    • https://growmytruck.com/wp-content/plugins/super-forms/uploads/php/files/6c6436d69929ca4ef79d7c0f9f88761b/xoxiga.pdf
    • http://www.nationaalgolfcongres.nl/wp-content/plugins/formcraft/file-upload/server/content/files/160a46b18f1675---vojifejunegukagob.pdf
    • https://feedproxy.google.com/~r/Uplcv/~3/YTWXjIUwRh0/uplcv?utm_term=friends+of+the+library+bookstore
    • 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_off0000d6e0.bin
92472fcf77ab9f02135be3a93daf5d3e727ea0af7dce29d3878c63f848839472
pdf-font-stream PDF embedded font (sfnt) at offset 0xD6E0 18460 bytes
font_01_sfnt_off00010745.bin
9460d4b55c29d114ac0587a9e3b0e7b750acc28903a2e464ef783e155668cddd
pdf-font-stream PDF embedded font (sfnt) at offset 0x10745 10776 bytes
font_02_sfnt_off00011ff5.bin
9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
pdf-font-stream PDF embedded font (sfnt) at offset 0x11FF5 16792 bytes