Malicious PDF — malware analysis report

Static analysis result for SHA-256 89f145f853956b82…

MALICIOUS

PDF

76.0 KB Created: 2021-04-22 18:59:24 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 4.8.7) First seen: 2021-09-27
MD5: a19ad2fab8ca10b983b3759ff17df894 SHA-1: 1026fc7ef1e4475dd389cb566a537695fa14d31a SHA-256: 89f145f853956b8293eafc188a9c59b822203c90fa4633dd2da0b4c3800827b5
126 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment T1059.007 JavaScript

This PDF file was flagged by multiple heuristics, including a critical ClamAV detection for 'Pdf.Phishing.Trojan' and an ML classifier indicating maliciousness. The presence of numerous external URIs, many pointing to disposable hosting and configured as a link farm, strongly suggests a phishing or malware distribution attempt. Although no scripts were explicitly extracted, the PDF structure and embedded URIs are indicative of malicious intent, likely to redirect users to malicious sites.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9998

Heuristics 5

  • ClamAV: Pdf.Phishing.Trojan-d2528dad23a95d95-d2528dad23a95d95-10044376-0 critical CLAMAV_DETECTION
    ClamAV detected this file as malware: Pdf.Phishing.Trojan-d2528dad23a95d95-d2528dad23a95d95-10044376-0
  • 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://vectorcorp.net/sites/default/files/webform/resume/86303695333.pdf In PDF document text
    • http://www.grotekeukens.be/sites/default/files/webform/gmawards2018/41850888982.pdfIn PDF document text
    • http://seiary.com/sites/default/files/webform/rec/netugapufuzutazegiwiwivi.pdfIn PDF document text
    • https://www.uts.cw/sites/default/files/webform/nukuromenalifaru.pdfIn PDF document text
    • http://www.birdlifebotswana.org.bw/sites/default/files/webform/sightings-sketches/fipeforivu.pdfIn PDF document text
    • https://vectorcorp.net/sites/default/files/webform/resume/tefofavokalozigukar.pdfIn PDF document text
    • http://www.friendlycc.com/sites/default/files/webform/85881129832.pdfIn PDF document text
    • http://www.pbttphtk.gov.my/sites/default/files/webform/fadubapep.pdfIn PDF document text
    • https://www.afscme65.org/system/files/webform/baxuwobokorexifiri.pdfIn PDF document text
    • https://www.termis.org/system/files/webform/dexifivoneput.pdfIn PDF document text
    • http://oaklandchildcare.org/sites/default/files/webform/zomosazufexebale.pdfIn PDF document text
    • https://ambrose.edu/sites/default/files/webform/11118021720.pdfIn PDF document text
    • https://www.dgs-interparts.be/sites/default/files/64751185730.pdfIn PDF document text
    • https://ambrose.edu/sites/default/files/webform/kepasibadugemefobovabo.pdfIn PDF document text
    • http://www.ascendercorp.com/In PDF document text
    • http://www.ascendercorp.com/typedesigners.htmlIn PDF document text
    • https://feedproxy.google.com/~r/Uplcv/~3/zMnd8XtcwSM/uplcv?utm_term=shark+iron+won%2527t+heat+upPDF link annotation
    • https://lib.asu.edu/system/files/webform/simadovi.pdfIn PDF document text
    • https://www.healthdata.org/sites/default/files/resumes/78922999772.pdfIn PDF document text
    • https://lib.asu.edu/system/files/webform/liwubuwivak.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://scripts.sil.org/OFLIn 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_off0000d8a0.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xD8A0 4988 bytes
SHA-256: 06db7da5c7f08f099f13f449b7afe9c08fd01393c9828a3217363a2d6ded9a80
font_01_sfnt_off0000e9ac.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xE9AC 10716 bytes
SHA-256: d7cf77465f5487452409e51d73bc8c0d32b3eeaafc3c450d9788c84f78ffdd75
font_02_sfnt_off00010e41.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x10E41 16060 bytes
SHA-256: 4ef9506ee11a349461550e6b437e3786686b598308a87786035880d16624999d