Malicious PDF — malware analysis report

Static analysis result for SHA-256 b880b17d6ae94374…

MALICIOUS

PDF

94.4 KB Created: 2021-06-29 21:25:15 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3)
MD5: 62adb47fa2dd5fdc934269d3e002a5df SHA-1: e6165f9903e9fb26dfdeef47826095d8e73fb497 SHA-256: b880b17d6ae94374c6168f43d7791658c698096d84ae024fe5d0c77764599f60
156 Risk Score

Malware Insights

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

The PDF contains numerous links, many pointing to compromised WordPress upload directories, suggesting a phishing or malware distribution attempt. The ML classifier and ClamAV detection strongly indicate malicious intent. The document body is unreadable binary data, but the heuristics and URLs are sufficient to infer a link farm attack pattern.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9956

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://stellabakingcompany.com/wp-content/plugins/formcraft/file-upload/server/content/files/1608c5fce173da---rutubowabu.pdf
    • http://beerskiboot.de/img/upload/file/bidezutimekorov.pdf
    • http://hrudolf.com/userfiles/sizijuvex.pdf
    • http://fmi.lu/userfiles/files/21890794847.pdf
    • http://www.ashtralmedia.com/wp-content/plugins/formcraft/file-upload/server/content/files/160a629d283546---diduzepedojasinube.pdf
    • https://sk-developers.com/wp-content/plugins/formcraft/file-upload/server/content/files/16071986d80712---junawogoxeremesu.pdf
    • https://www.potterycommercials.co.uk/wp-content/plugins/formcraft/file-upload/server/content/files/160a0a95bb1f73---7916821441.pdf
    • http://ghalemdi.com/userfiles/file/babefigunu.pdf
    • https://www.uniqueartzz.com/wp-content/plugins/super-forms/uploads/php/files/b05ciornrmsjq51gcd1q9igc3b/kojenejebisivulol.pdf
    • http://jjinline.org/file_upload/file/34656693564.pdf
    • http://universe-micro.com/upload/files/20210625_195013.pdf
    • https://chrmglobal.com/userfiles/file/53823343864.pdf
    • https://forumhotel.by/wp-content/plugins/super-forms/uploads/php/files/5vlbqv4cehofd10bkfh8d2php7/xagijifipug.pdf
    • http://www.kzhep.in.ua/wp-content/plugins/super-forms/uploads/php/files/mv2n7ld0hpam7lmo0smc6jdoo3/35952085447.pdf
    • http://accessiblevehicleservices.com/userfiles/file/26884217823.pdf
    • http://audiencefertilization.com/fckeditor/editor/filemanager/connectors/php/userfiles/file/risokog.pdf
    • http://www.deopendeur.org/imgUser/file/tesarosiza.pdf
    • http://jfhconsultancy.nl/userfiles/files/15995376780.pdf
    • https://www.audifonosdoshoydos.com/wp-content/plugins/formcraft/file-upload/server/content/files/160895bca09d33---weruvexofe.pdf
    • http://www.sunarpazarlama.com/wp-content/plugins/super-forms/uploads/php/files/u7osplaamr47rg8n0bccft5fd7/piwaxebofebuloluvi.pdf
    • https://atolab.it/wp-content/plugins/super-forms/uploads/php/files/45656b518c5bfdcaa87fe5aab13bb4d6/76309728090.pdf
    • https://www.pfgpartners.com.au/wp-content/plugins/formcraft/file-upload/server/content/files/160cd531056647---zedoduxafodawa.pdf
    • https://feedproxy.google.com/~r/Uplcv/~3/zMnd8XtcwSM/uplcv?utm_term=free+radical+substitution
    • 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_off00010b4a.bin
173c198a8e9d4a89f320a947913c2e703de61d9b0dda2b3633f67c174ba37551
pdf-font-stream PDF embedded font (sfnt) at offset 0x10B4A 18460 bytes
font_01_sfnt_off00013c8c.bin
9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
pdf-font-stream PDF embedded font (sfnt) at offset 0x13C8C 16792 bytes
font_02_sfnt_off000154a3.bin
55a7a970d35f553ef02f2e3e3d47b34968b32c5eafbaa431d14e15d911ec5f43
pdf-font-stream PDF embedded font (sfnt) at offset 0x154A3 10580 bytes