Malicious PDF — malware analysis report

Static analysis result for SHA-256 21054774d7786378…

MALICIOUS

PDF

75.7 KB Created: 2021-07-08 12:24:16 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3)
MD5: afb88b4a54f7da214439efcc03dfc1ca SHA-1: 6a80d264ee2c85a4084ce6cdbc87fa72dae826f9 SHA-256: 21054774d77863782120d1af84a82866cf8f76543b15633d8b556b23a87f5b25
172 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment

The sample was detected as malicious by ClamAV and an ML classifier, indicating a high likelihood of malicious intent. It contains embedded JavaScript and numerous external links, many pointing to compromised WordPress sites or disposable hosting, suggesting it functions as a lure to external resources. The presence of PDF_JS indicates the embedded JavaScript is likely used to facilitate the redirection or exploit.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9994

Heuristics 8

  • 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.
  • 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.
  • Urgency / deadline lure low SE_URGENCY_LURE
    Document contains urgency or deadline language ('account will be terminated', 'action required within 24 hours', etc.) — useful context, but low-signal without other findings
  • 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://willmarlakesarea2040.com/ckfinder/userfiles/files/51642307386.pdf
    • https://acethamessecurity.co.uk/wp-content/plugins/super-forms/uploads/php/files/d99c8a6aa86a2a0d6df12b87fc77d146/97217229578.pdf
    • https://nutricionintravenosa.com/wp-content/plugins/super-forms/uploads/php/files/f43a92508a6cb1f33d96a531c2e9bd76/xukolivil.pdf
    • http://garageanything.com/js/upload/files/kowogesevasol.pdf
    • http://verkoop-je-wagen.be/wp-content/plugins/formcraft/file-upload/server/content/files/1608baf105e289---wuwuwav.pdf
    • https://theemperorsoldclothes.co.uk/wp-content/plugins/super-forms/uploads/php/files/mo2surrv83jvh6pj8gdjq02kmj/sebutuxejenubof.pdf
    • https://mangonebike.com/uploads/file/retedo.pdf
    • https://chocoinmobiliario.com/wp-content/plugins/super-forms/uploads/php/files/5aa0dd8bbcf8f2a7eb631f9b04185619/78256852633.pdf
    • http://www.empresshasnoclothes.com/siteuploads/editorimg/file/zomazene.pdf
    • http://bjsixiang.com/jingkelun/userfiles/files/20210701143717.pdf
    • http://ideatity.com/ckfinder/userfiles/files/23512046401.pdf
    • http://trenermichal.pl/wp-content/plugins/formcraft/file-upload/server/content/files/1608d9438776f8---5397330456.pdf
    • http://go-pxl.com/uploads/files/murugapawamiwejifa.pdf
    • https://stegopackaging.com/wp-content/plugins/super-forms/uploads/php/files/tmpcq5viot62mto9n643at33f1/fopexijumalujuloxafugez.pdf
    • http://saxonrt.hu/img/userfiles/files/xapijelafajufed.pdf
    • https://www.ideaklinikankara.com/wp-content/plugins/formcraft/file-upload/server/content/files/16073062980444---zixiranemejinozinuvavo.pdf
    • https://www.swissfillon.com/wp-content/plugins/super-forms/uploads/php/files/460ff2a15b1bfab3ab0e2c8f436f244b/watifitijatezuva.pdf
    • https://connect.allianceflooring.net/wp-content/plugins/super-forms/uploads/php/files/740ef1421dd84385c6729f327e2d9e22/tagixut.pdf
    • https://feedproxy.google.com/~r/Uplcv/~3/1KS0DP0cxss/uplcv?utm_term=precalculus+with+limits+third+edition+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_off0000c406.bin
c3e1f9a9ba1cb60dc134609905d49d576d73ef2a6ee307a2db53f932127248b9
pdf-font-stream PDF embedded font (sfnt) at offset 0xC406 10824 bytes
font_01_sfnt_off0000dcdb.bin
1dc2089b437e41f80bfc1207e4d7a542db896ef676746ff45b7c60eb93f9df0b
pdf-font-stream PDF embedded font (sfnt) at offset 0xDCDB 17032 bytes
font_02_sfnt_off000108f5.bin
9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
pdf-font-stream PDF embedded font (sfnt) at offset 0x108F5 16792 bytes