Malicious PDF — malware analysis report

Static analysis result for SHA-256 b8319373d3203ce5…

MALICIOUS

PDF

81.8 KB Created: 2021-09-23 05:16:44 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-11-02
MD5: 7f7064598d048f05002262cb5b007821 SHA-1: 0447059a589eacc46b00ce0627104d8ed38a2706 SHA-256: b8319373d3203ce5e5c67b7e5273a6497b4d953e789a8a603bbd50daf74e5ace
156 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment T1204.002 Malicious Link

This PDF file was flagged by a machine learning classifier and ClamAV as malicious, specifically as a phishing trojan. It functions as a link farm, containing numerous embedded URLs that point to various websites, some of which are hosted on compromised CMS uploads. The primary purpose appears to be directing users to external, potentially malicious content.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9964

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://shrmivirtual.org/wp-content/plugins/super-forms/uploads/php/files/f4738b89f3d92390a30f5dd61c016692/68022420887.pdf In PDF document text
    • http://hamyarsanatco.com/ckfinder/userfiles/files/86761078167.pdfIn PDF document text
    • https://citronel.com/userfiles/files/taxexapimojanupagupakepu.pdfIn PDF document text
    • https://wodepcb.cn/uploadfiles/files/rozatimuwaxigutipixovumet.pdfIn PDF document text
    • http://studiotecnicoligioni.com/userfiles/files/domizipiperukoxegeke.pdfIn PDF document text
    • http://autoset66.ru/admin/ckfinder/userfiles/files/99692263856.pdfIn PDF document text
    • https://volgogradexpo.ru/ckfinder/userfiles/files/99273643699.pdfIn PDF document text
    • http://lj-group.cn/upload/files/76870190394.pdfIn PDF document text
    • http://nceed.kr/pds/userfiles/files/puzorojuxazomojutuguvo.pdfIn PDF document text
    • https://studybrilliant.online/app/webroot/img/userfiles/file/15714243717.pdfIn PDF document text
    • http://hpworld.hu/data/pic/Image/file/80339342457.pdfIn PDF document text
    • http://trenermichal.pl/wp-content/plugins/formcraft/file-upload/server/content/files/1614bd0106dad3---fozed.pdfIn PDF document text
    • https://sesconbs.org.br/ckfinder/userfiles/files/79172939431.pdfIn PDF document text
    • http://www.dean-cpa.com/files/adminpic/file/50446921931.pdfIn PDF document text
    • http://zoncmswebsitebeheer.nl/files/editor/file/8784542498.pdfIn PDF document text
    • http://myhomeinparis.com/userfiles/files/jeriruzomemiwunagiz.pdfIn PDF document text
    • http://oishisushigd.com/uploads/files/josaja.pdfIn PDF document text
    • http://tavaszitura.eu/userfiles/files/26662195816.pdfIn PDF document text
    • http://busangh.com/attfile/fckimg/file///2021091121529_574853909.pdfIn PDF document text
    • http://ansing.nl/userfiles/file/10866526869.pdfIn PDF document text
    • https://webgirls-studio.com/wp-content/plugins/formcraft/file-upload/server/content/files/16148e699a6313---mimepafukajibikugezan.pdfIn PDF document text
    • http://aqbnb.com/uploadfile/file/75603224310.pdfIn PDF document text
    • https://feedproxy.google.com/~r/1eyvgo/aqOO/~3/cv9VXjIrmdE/uplcv?utm_term=java+lang+unsatisfiedlinkerror+can+t+load+libraryPDF link annotation
    • 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_off0000d3a0.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xD3A0 11152 bytes
SHA-256: af3acbb9e2e3454bd27599a39badb6fbb1b860b87ee0effd0a5bdf393f9a89bb
font_01_sfnt_off0000edab.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xEDAB 19604 bytes
SHA-256: 40e5ac4c5c411c8354d7b3320e7e482d487c86ee4fc9735773f6aa5616520bd7
font_02_sfnt_off00012188.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x12188 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1