Malicious PDF — malware analysis report

Static analysis result for SHA-256 1ac65f9a107fbbec…

MALICIOUS

PDF

78.4 KB Created: 2021-09-16 09:51:40 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-10-27
MD5: 86966b1e8e44d3943f16dc46eb9eeeee SHA-1: cc001d2a25eae6bd3e8babe8308730209ecff4a0 SHA-256: 1ac65f9a107fbbec609f02b82e4f7da0cf77b0f5018cf711d39ff34ae7b50652
126 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment

The PDF contains a large number of embedded links pointing to various domains, many of which appear to be disposable or low-reputation hosting. The heuristic 'PDF_SEO_DISPOSABLE_LINK_FARM' strongly suggests a link farm intended to redirect users to malicious content. The ML classifier and ClamAV detection further confirm the malicious nature of the file, likely as a phishing or malware distribution vector.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9953

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://nomylo.ru/uplcv?utm_term=piratebay+unblock+list PDF link annotation
    • http://ensky-chemical.com/upload/files/nupiluwanixopovatus.pdfIn PDF document text
    • https://mehfermobilsaglik.com/userfiles/file/22677049754.pdfIn PDF document text
    • https://collinite.pl/userfiles/file/81182794216.pdfIn PDF document text
    • http://ingpiazza.eu/userfiles/files/6923968036.pdfIn PDF document text
    • http://bestapp4u.com/admin/uploadedfiles/file/98354757511.pdfIn PDF document text
    • http://alacartedesign.de/userfiles/file/zazawepepinarizi.pdfIn PDF document text
    • https://gz-topstar.com/wp-content/plugins/super-forms/uploads/php/files/004083638779b3533d0c03218048f4c2/nameditetufodamuj.pdfIn PDF document text
    • http://bigcool.net/webroot/img/files/nosemanab.pdfIn PDF document text
    • http://francescofesta.it/userfiles/files/82619431237.pdfIn PDF document text
    • http://squarcialupirelaxinchianti.com/writable/public/userfiles/file/32507857661.pdfIn PDF document text
    • http://sinching.com/uploadpic/files/202109031450469258.pdfIn PDF document text
    • http://bulk-supplies.com/userfiles/files/povitiremukagawogamutig.pdfIn PDF document text
    • https://www.gpaci.org.br/cms/ckfinder/userfiles/files/72472208768.pdfIn PDF document text
    • http://thevalleytrader.com/files/nigomokov.pdfIn PDF document text
    • http://tucholainfo.pl/userfiles/file/5760624940.pdfIn PDF document text
    • https://solturism.ro/images/file/10898653849.pdfIn PDF document text
    • https://www.sistemkabin.com/ckfinder/userfiles/files/87112664249.pdfIn PDF document text
    • http://tuvanluatdanang.com/upload/ck/files/vagozawit.pdfIn PDF document text
    • https://hlj-vibration.com/uploads/image/20210904/files/20210904155757.pdfIn PDF document text
    • http://chuanghuilaw.com/filespath/files/20210911213331.pdfIn PDF document text
    • https://concertwristband.com/resimler/files/mazesibob.pdfIn PDF document text
    • http://bagandpack.ru/wp-content/plugins/super-forms/uploads/php/files/b7a493cfbd1935668adf48236d8a2503/48099700238.pdfIn PDF document text
    • http://abwfinlay.com/uploads/files/vutiladerufegiluzawimep.pdfIn PDF document text
    • https://ntpuvoice.com/ckfinder/userfiles/files/82852319571.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://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_off0000ce4e.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xCE4E 17564 bytes
SHA-256: b8512b26b302539ca1dda7914b8432315f7e5c02c1b8e7844858355aae85cb1b
font_01_sfnt_off0000fbcb.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xFBCB 10668 bytes
SHA-256: d4335fb56d543fd7c843ec2408d876067cea7d858d2183bebed4ff5b3539342f
font_02_sfnt_off0001146f.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x1146F 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1