Malicious PDF — malware analysis report

Static analysis result for SHA-256 a831dc79edb87ae0…

MALICIOUS

PDF

80.7 KB Created: 2021-08-13 13:14:43 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-10-31
MD5: 0fd784e1886ba9314cfa745ffb7a22c5 SHA-1: d499268a6e8c41e3c6f0966e0107a73efeaffc35 SHA-256: a831dc79edb87ae07a832939c40a8470ccb924d81ef811c35651fb9b9144bbf2
184 Risk Score

Malware Insights

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

This PDF file was detected as malicious by ClamAV and an ML classifier, indicating a high likelihood of malicious intent. The embedded JavaScript stream and external URIs suggest the document is designed to redirect users to malicious websites, potentially for phishing or to download further payloads. The heuristic 'SE_CALLBACK_LURE' further suggests a phishing pretext, possibly related to billing or subscription scams.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9977

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.
  • Callback phishing phone lure medium SE_CALLBACK_LURE
    Document asks the user to call a phone number in billing, refund, subscription, fraud, or security context — consistent with callback phishing or tech-support scam patterns. Suppressed for legitimate-issuer (IRS/gov/official-form) documents that carry no urgency or charge/dispute escalation.
  • 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.
  • 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://infrive.ru/uplcv?utm_term=pre+authorized+debit+form+scotiabank PDF link annotation
    • https://www.saltriot.com/wp-content/plugins/super-forms/uploads/php/files/f2377acabe72d8254781ed931c1c48f2/34597652563.pdfIn PDF document text
    • https://ercrs.org/wp-content/plugins/super-forms/uploads/php/files/rkeepm8gk3lqb10cv1pkqkuq45/50384151266.pdfIn PDF document text
    • https://jdlpartnerss.com/userfiles/file/benogixodipewot.pdfIn PDF document text
    • https://independentmusicleague.com/wp-content/plugins/super-forms/uploads/php/files/030e92155692a9dbe5e97193d74295b5/30129248399.pdfIn PDF document text
    • https://grandplaza.bg/uploads/assets/file/15794941301.pdfIn PDF document text
    • http://liavanhaeringen.nl/userfiles/files/6004249383.pdfIn PDF document text
    • https://sjalikave.hu/pictures/file/lomevolozetobawurapoke.pdfIn PDF document text
    • http://everest-c.ru/ckfinder/userfiles/files/wepofoxanironeze.pdfIn PDF document text
    • https://novahealthclinic.ca/userfiles/file/wafawerikelumigeba.pdfIn PDF document text
    • https://abugfreemind.com/userfiles/file/22432893310.pdfIn PDF document text
    • https://goez3.com/10005001208290177/ckfinder/userfiles/files/6767961273.pdfIn PDF document text
    • https://iwistw.com/upload/files/33928641482.pdfIn PDF document text
    • https://www.infrascale.com/wp-content/plugins/super-forms/uploads/php/files/42aec2d0a811171ca026c0fc34452eb8/bamonikoxigudepinivev.pdfIn PDF document text
    • https://earthchartercities.org/wp-content/plugins/formcraft/file-upload/server/content/files/160843f4321bee---xigipezelukatajezirugi.pdfIn PDF document text
    • http://portalkucharski.pl/app/webroot/media/files/19968058935.pdfIn PDF document text
    • https://pilot-nav.com/ckfinder/userfiles/files/42490553832.pdfIn PDF document text
    • http://2sisaccount.com/userfiles/files/70524636744.pdfIn PDF document text
    • http://baugeraeteverleih.de/benutzerdateien/29545933637.pdfIn PDF document text
    • http://aviapartner.biz/js/ckfinder/userfiles/files/18997833618.pdfIn PDF document text
    • https://anmoul.com/userfiles/file/92548543857.pdfIn PDF document text
    • https://www.burit.net/wp-content/plugins/formcraft/file-upload/server/content/files/160db9dddd847d---jemuzosawof.pdfIn PDF document text
    • https://batdongsandothanh.vn/luutru/files/62920661394.pdfIn PDF document text
    • http://geoscan.it/userfiles/files/48339718271.pdfIn PDF document text
    • http://www.w3.org/1999/02/22-rdf-syntax-ns#In PDF document text
    • http://purl.org/dc/elements/1.1/In PDF document text
    • http://ns.adobe.com/pdf/1.3/In PDF document text
    • http://ns.adobe.com/xap/1.0/In PDF document text
    • http://ns.adobe.com/xap/1.0/mm/In PDF document text
    • http://ns.adobe.com/xap/1.0/rights/In PDF document text
    • http://dejavu.sourceforge.netIn PDF document text
    • http://dejavu.sourceforge.net/wiki/index.php/LicenseIn PDF document text

Extracted artifacts 3

Files carved from inside the sample during analysis.

FilenameKindSourceSize
font_00_sfnt_off0000d898.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xD898 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
font_01_sfnt_off0000f0aa.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xF0AA 16400 bytes
SHA-256: 1d681737506b9885365f443c4fe4d9992d6a33cec447c0f63ed972c2bc4e97ca
font_02_sfnt_off00011b57.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x11B57 11088 bytes
SHA-256: 1dc8ad1971f4e44d8a627a8d232108827a1870a724e871f4b4767e2ffdd7adff