Malicious PDF — malware analysis report

Static analysis result for SHA-256 b145030b9df58112…

MALICIOUS

PDF

73.0 KB Created: 2021-09-19 10:51:33 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-10-27
MD5: 42b6dabcc76288b0578575ebc1162f03 SHA-1: 5a73d5f8d3ce94d0f8d1d0f957cdaa87fd0bdeb1 SHA-256: b145030b9df5811207e2e4aa337148f3a565910f0f38bb62b626a5bc47cb281a
126 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment T1204.002 Malicious Link

The PDF was flagged by ClamAV as Pdf.Phishing.Trojan and a machine learning classifier indicated a high probability of maliciousness. The heuristic 'PDF_SEO_DISPOSABLE_LINK_FARM' indicates the document is designed as a link farm, likely to obscure the true destination and distribute malicious content. Numerous URLs were extracted, many of which are hosted on domains that appear to be part of this link farm, suggesting a phishing or malware distribution campaign.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9951

Heuristics 5

  • ClamAV: Pdf.Phishing.Trojan-d2568dad23a94d95-d2568dad23a94d95-10044375-0 critical CLAMAV_DETECTION
    ClamAV detected this file as malware: Pdf.Phishing.Trojan-d2568dad23a94d95-d2568dad23a94d95-10044375-0
  • 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://yastudio.net/wp-content/plugins/super-forms/uploads/php/files/f7f8fabaac39202400082d8e4948eb1e/81178934847.pdf In PDF document text
    • https://ckfinder.pamlskovnik.cz/ckfinder/userfiles/files/11205468797.pdfIn PDF document text
    • https://middletonchambers.com/ckfinder/userfiles/files/topofi.pdfIn PDF document text
    • http://americandeliorder.com/uploads/files/27503680568.pdfIn PDF document text
    • https://soudurelauziere.com/upload/editor/file/tefar.pdfIn PDF document text
    • https://juniorclublivorno.com/sitonews/images_upload/files/40054481530.pdfIn PDF document text
    • http://forma8.kz/ckfinder/userfiles/files/zuzekimipomidomi.pdfIn PDF document text
    • https://limadelimon.com/images/file/towapen.pdfIn PDF document text
    • http://batterseataxi.com/survey/userfiles/files/vebopamubapejawej.pdfIn PDF document text
    • http://songhakbbq.com/uploads/files/lamavogasal.pdfIn PDF document text
    • https://vicotelecom.vn/static/source/images/file/2489049179.pdfIn PDF document text
    • http://gdlejia.com/uploadfile/files/20210901_133333.pdfIn PDF document text
    • https://www.milestonesmn.org/ckfinder/userfiles/files/91673327021.pdfIn PDF document text
    • http://bielle-srl.com/userfiles/files/lafuwizimikiduk.pdfIn PDF document text
    • http://brixtontaxi.com/survey/userfiles/files/juripemuk.pdfIn PDF document text
    • http://thanglong.vn-greenenergy.com/ckfinder/userfiles/files/31507388076.pdfIn PDF document text
    • http://www.moyekolodin.com/files/79458167606.pdfIn PDF document text
    • http://dekoblickfang.de/userfiles/file/10761582507.pdfIn PDF document text
    • http://nriloan.jctoursandtravels.in/files/rofewofu.pdfIn PDF document text
    • https://mcq-exambd.com/app/webroot/ckfinder/userfiles/files/82978936067.pdfIn PDF document text
    • http://stoka-saarlouis.de/userfiles/file/pivumipifi.pdfIn PDF document text
    • https://franchisefarm.franchiseharbor.com/files/files/43370483469.pdfIn PDF document text
    • http://www.veslovani-vsb.cz/soubory/file/70745839884.pdfIn PDF document text
    • http://onsijsselstein.nl/userfiles/files/2130443852.pdfIn PDF document text
    • https://feedproxy.google.com/~r/1eyvgo/aqOO/~3/ngfLrbzwjls/uplcv?utm_term=android+development+pptPDF 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_off0000bbaa.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xBBAA 10272 bytes
SHA-256: 37a5ddf28563f37de0f48fe2fe8f23ef5b1f0897ca6c91cec58d599c5c21f1f5
font_01_sfnt_off0000d2ab.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xD2AB 16884 bytes
SHA-256: 2723684baddb3245f21730d5d1a664c603fa178e2796503228fc02bf5595b8d0
font_02_sfnt_off0000feb3.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xFEB3 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1