Malicious PDF — malware analysis report

Static analysis result for SHA-256 8a736495b1a879fe…

MALICIOUS

PDF

82.8 KB Created: 2021-09-12 23:51:47 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-10-07
MD5: 99af951fee40d7d586ed9ccfaf98f64d SHA-1: ca13b8cbbb1d05dd7429ec4b6fb774ecc03cc161 SHA-256: 8a736495b1a879fe4acb6561142094c45865bd77c30a7ff956284269b08732f0
156 Risk Score

Malware Insights

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

The PDF document was flagged by ML classifiers and ClamAV as malicious, specifically as a phishing trojan. It contains numerous embedded URLs, many of which point to compromised CMS uploads or disposable hosting, suggesting an attempt to lure users to external sites. The document body is heavily obfuscated, preventing a clear understanding of its direct intent beyond hosting these links.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9955

Heuristics 6

  • ClamAV: Pdf.Phishing.Trojan-d2528dad23a95d95-d2528dad23a95d95-10044376-0 critical CLAMAV_DETECTION
    ClamAV detected this file as malware: Pdf.Phishing.Trojan-d2528dad23a95d95-d2528dad23a95d95-10044376-0
  • 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 http://smenergy.kr/uploaded/file/1240499625613e33b36a881.pdf In PDF document text
    • https://hunglivet.com/uploads/files/202108311818176253.pdfIn PDF document text
    • http://studioaeditecne.it/userfiles/file/moremoriwalaje.pdfIn PDF document text
    • https://pilot-nav.com/ckfinder/userfiles/files/xokabonogagufirewejefodo.pdfIn PDF document text
    • http://crm333.com/documentos/file/12346478509.pdfIn PDF document text
    • https://growlocals.com/wp-content/plugins/super-forms/uploads/php/files/302cf65360e6eebda1619ff2d2184f10/45728725737.pdfIn PDF document text
    • http://onelove.cz/file/65396632976.pdfIn PDF document text
    • http://humidorio.de/ckfinder/userfiles/files/38939586661.pdfIn PDF document text
    • http://urs-certification.com/gais/image/file/20357790526.pdfIn PDF document text
    • https://chief-moving.com/editor_upload/file/nuzexebafojatemi.pdfIn PDF document text
    • https://www.hit-education.com/wp-content/plugins/super-forms/uploads/php/files/davc9lo86pm919jbdg1ii61b74/79092139407.pdfIn PDF document text
    • https://www.tcf.gov.tr/ckfinder/userfiles/files/nixodinonupovajakuvofuvir.pdfIn PDF document text
    • http://origo.ws/userfiles/file/jovefowavavajafepa.pdfIn PDF document text
    • http://volkshilfe-ktn.at/images/content/files/satixijabodamu.pdfIn PDF document text
    • http://wenyanchem.com/upload/files/82327505772.pdfIn PDF document text
    • http://andreaslasnik.com/data/files/41223225662.pdfIn PDF document text
    • http://abwclayton.com/uploads/files/22807089735.pdfIn PDF document text
    • https://geneticapanama.com/userfiles/file/66089541968.pdfIn PDF document text
    • http://www.fred-robin.com/ckfinder/userfiles/files/buwojipuke.pdfIn PDF document text
    • https://www.pferde-fuer-unsere-kinder.de/wp-content/plugins/formcraft/file-upload/server/content/files/161336aee6b20b---mubum.pdfIn PDF document text
    • https://tyko.pl/userfiles/file/59149497006.pdfIn PDF document text
    • http://osoboebludo.com/ckfinder/userfiles/files/gajar.pdfIn PDF document text
    • http://csaladiegyteruautok.hu/userfiles/files/2204294223.pdfIn PDF document text
    • http://agro-pasz.pl/ckfinder/userfiles/files/tesufatudafoxojafom.pdfIn PDF document text
    • https://feedproxy.google.com/~r/skout/mBVl/~3/3vuEKuznOb8/uplcv?utm_term=point+blank+pathfinderPDF 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_off0000ddb9.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xDDB9 10660 bytes
SHA-256: ec78612c7f809ac36277658c941bc27439743cf269986ccd0ff81ffc07264815
font_01_sfnt_off0000f5c9.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xF5C9 18400 bytes
SHA-256: 55209797bcb53265868db046c3eb83a267d25ef8496e9891f38aad3fb488ea81
font_02_sfnt_off000125b5.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x125B5 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1