Malicious PDF — malware analysis report

Static analysis result for SHA-256 de82fa13d9ca63d8…

MALICIOUS

PDF

82.0 KB Created: 2021-04-13 18:47:07 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 4.8.7) First seen: 2021-05-29
MD5: a40064f8ed0031e676174b036005a4e4 SHA-1: b3c21d6147a9ce38c3bcaca6500619209e2e42c9 SHA-256: de82fa13d9ca63d8ffb853498003b85c58ec2f0ed0cdf2653df74da30df5a1ac
126 Risk Score

Malware Insights

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

The PDF contains numerous embedded URLs, with a high heuristic score indicating it is a link farm hosted on disposable domains. The ML classifier and ClamAV detection strongly suggest malicious intent, likely related to phishing or malware distribution. While no scripts were directly extracted, the PDF structure and embedded URIs point towards a malicious document designed to redirect users to further malicious content.

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 http://www.friendlycc.com/sites/default/files/webform/kilolegejesap.pdf In PDF document text
    • https://architecturaldesigninc.com/sites/default/files/72694480293.pdfIn PDF document text
    • https://www.blplegal.com/sites/default/files/webform/3097059720.pdfIn PDF document text
    • https://vectorcorp.net/sites/default/files/webform/resume/tefofavokalozigukar.pdfIn PDF document text
    • https://ambrose.edu/sites/default/files/webform/lajeriz.pdfIn PDF document text
    • https://www.a1touchsolution.nl/sites/default/files/26511902049.pdfIn PDF document text
    • http://www.birdlifebotswana.org.bw/sites/default/files/webform/sightings-sketches/13349970620.pdfIn PDF document text
    • https://www.uts.cw/sites/default/files/webform/96040264728.pdfIn PDF document text
    • https://natsihwa.org.au/sites/default/files/webform/mufuwujaxerafesa.pdfIn PDF document text
    • https://www.pharoxglobal.com/sites/default/files/webform/garuwofewitenobakufenewi.pdfIn PDF document text
    • http://russian-ice-spb.ru/sites/default/files/webform/files/32020734574.pdfIn PDF document text
    • https://www.jts.org.jo/sites/default/files/webform/76938035167.pdfIn PDF document text
    • http://pilgrimland.com/sites/default/files/webform/resume-uploads/40494538869.pdfIn PDF document text
    • http://russian-ice-spb.ru/sites/default/files/webform/files/zatepatepekaberemosigedix.pdfIn PDF document text
    • https://www.uts.cw/sites/default/files/webform/58994315224.pdfIn PDF document text
    • http://www.ascendercorp.com/In PDF document text
    • http://www.ascendercorp.com/typedesigners.htmlIn PDF document text
    • http://www.daltonmaag.com/In PDF document text
    • https://feedproxy.google.com/~r/Uplcv/~3/BkSY9tpko7c/uplcv?utm_term=dewalt+manual+brad+nailerPDF link annotation
    • https://campusrec.princeton.edu/system/files/webform/7624886728.pdfIn PDF document text
    • https://www.ice.cam.ac.uk/sites/www.ice.cam.ac.uk/files/webform/xegenaxug.pdfIn PDF document text
    • https://drones.princeton.edu/system/files/webform/65601020807.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

Extracted artifacts 3

Files carved from inside the sample during analysis.

FilenameKindSourceSize
font_00_sfnt_off0000f583.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xF583 4796 bytes
SHA-256: a46c5fd9c3c7559acd299d7eafcd9749bad3c7c08ac5fef1233bddeee5fae65c
font_01_sfnt_off000105b9.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x105B9 11532 bytes
SHA-256: f85f84e77fbcd529a40614ee45db9235fcc9e9c6831da06217001cc2edbd92e2
font_02_sfnt_off00012cd3.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x12CD3 4324 bytes
SHA-256: 05d2457133b820fa77aa358e30e9acfbad3f04c46ced9a37296d9311117db176