Malicious PDF — malware analysis report

Static analysis result for SHA-256 b526840ba52e55a5…

MALICIOUS

PDF

82.4 KB Created: 2021-09-05 04:17:23 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-10-27
MD5: 72ccaaa7731a9e0789a15b488d56f69c SHA-1: c91850f69fbd7201fc26778239c884f2988ec609 SHA-256: b526840ba52e55a5bbfcc58495bbf346c3769f0e9916602a750e8383fa976bd5
156 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment

This PDF file was detected as malicious by ClamAV and an ML classifier. It functions as a link farm, presenting numerous URLs hosted on compromised websites, likely to direct users to malicious content. The presence of multiple PDF link farm heuristics indicates a deliberate attempt to obscure the final malicious destination.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9985

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 https://archltginc.com/wp-content/plugins/super-forms/uploads/php/files/b0abaaa0390581fe9c7560ecf39044be/tiniputijo.pdf In PDF document text
    • http://dunajecbiala.pl/upload/File/20990163258.pdfIn PDF document text
    • http://mastrodibaglio.it/userfiles/files/tawevon.pdfIn PDF document text
    • https://jensbrode.de/files/file/71659407754.pdfIn PDF document text
    • https://gppacdatabase.net/userfiles/file/45284253143.pdfIn PDF document text
    • http://www.lightingandhvacexpo.com/wp-content/plugins/super-forms/uploads/php/files/3fdbe19e884f0965f89298ae20443c26/46156145994.pdfIn PDF document text
    • http://sadiqandsons.com/userfiles/files/52853153902.pdfIn PDF document text
    • https://www.profiemg.cz/upload/ck/files/komisowemux.pdfIn PDF document text
    • http://peetersinstallatietechniek.nl/upload/files/94655629101.pdfIn PDF document text
    • http://alpha-th.com/userfiles/file/83474660120.pdfIn PDF document text
    • http://nhuaduongnhapkhauaz.info/upload/files/lopibilaselodu.pdfIn PDF document text
    • http://animalscipublisher.com/files/upfiles/file/laderekoko.pdfIn PDF document text
    • https://www.beewellrx.com/wp-content/plugins/super-forms/uploads/php/files/tmp/luwisotozal.pdfIn PDF document text
    • http://hanleyresources.com/images/zefipobo.pdfIn PDF document text
    • http://www.mkkdigital.pt/wp-content/plugins/formcraft/file-upload/server/content/files/160877d865877d---demimipafozuvat.pdfIn PDF document text
    • http://plymouth-logs.co.uk/ckfinder/userfiles/files/vemof.pdfIn PDF document text
    • http://cochu.net/resimler/files/51643157128.pdfIn PDF document text
    • https://ailani.org/wp-content/plugins/super-forms/uploads/php/files/00c95ff8513b53a3a82b9e82fbb37c18/31880168061.pdfIn PDF document text
    • http://mirrorgallery.com/wp-content/plugins/formcraft/file-upload/server/content/files/1607e45c07fa2a---lonofa.pdfIn PDF document text
    • https://www.m2asolutions.com/wp-content/plugins/super-forms/uploads/php/files/de13c3f8d9501e38fed007c9743477c7/febirikegeku.pdfIn PDF document text
    • http://cpils.com/userfiles/file/6013803251.pdfIn PDF document text
    • https://feedproxy.google.com/~r/1eyvgo/aqOO/~3/zMnd8XtcwSM/uplcv?utm_term=grade+9+science+worksheets+ontarioPDF 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_off0000d900.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xD900 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
font_01_sfnt_off0000f117.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xF117 10804 bytes
SHA-256: a4f3acf89048090deeacfba8e33cdee9ca060c57482a65b537fab958336084b3
font_02_sfnt_off00010a08.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x10A08 19936 bytes
SHA-256: cc3aac90ecc0d177fbbacd5ba4a26fac5eb783aee9b0bf3d8fd3925e78110858