Malicious PDF — malware analysis report

Static analysis result for SHA-256 2145f57a4c0d1f75…

MALICIOUS

PDF

84.4 KB Created: 2021-09-16 17:36:34 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-10-12
MD5: deec429a0e40b8a30dfe6676e7bba26a SHA-1: 84fd04543455d1e3b7d38d7c1666628cf8997bde SHA-256: 2145f57a4c0d1f7590197270e384afd43adf5cfdcd074e61e5dc6ff9c2af82c4
134 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment

The sample was detected by multiple heuristics and an ML classifier as malicious, with ClamAV identifying it as a phishing trojan. The PDF contains embedded JavaScript, which is often used to redirect users to malicious websites or download further payloads. The presence of numerous external URIs, many pointing to potentially disposable domains, further supports a phishing or link-farming attack pattern.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9956

Heuristics 6

  • 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.
  • Embedded JS stream low PDF_JS
    PDF references a /JS stream. Generic JavaScript is common in benign forms; specific dangerous APIs are scored by separate rules.
  • 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://masterok-kovka.ru/wp-content/plugins/super-forms/uploads/php/files/b9c7e1c1552db12f8861c5637db7d78b/52657780491.pdf In PDF document text
    • http://aviapartner.biz/js/ckfinder/userfiles/files/doseg.pdfIn PDF document text
    • http://laboratoriodiprogettazione-ve.it/userfiles/files/51445962417.pdfIn PDF document text
    • http://myucpb.com/userfiles/file/jawilojumekeropapiroxin.pdfIn PDF document text
    • http://zhihepvb.com/upload/ckimg/files/202109051251098977.pdfIn PDF document text
    • http://clairerolo.com/userfiles/file/30865773483.pdfIn PDF document text
    • https://ego-sofa.tw/uploads/files/202109050605225461.pdfIn PDF document text
    • https://alicantea.centralcms.cloud/galeria/files/10522172238.pdfIn PDF document text
    • https://woft-dining.com/webroot/editor-uploads/files/potafisizose.pdfIn PDF document text
    • http://clairvoyantinfotech.com/demo/images/30489024296.pdfIn PDF document text
    • https://onlineadda.organicemall.com/ckfinder/userfiles/files/gaxukogenojiwonesijakago.pdfIn PDF document text
    • http://centrons.com/uploaded/file/68500661861375fbfd36e5.pdfIn PDF document text
    • http://carsonpokebar.com/uploads/files/89557156602.pdfIn PDF document text
    • https://atkarisuli.hu/userfiles/file/64009449384.pdfIn PDF document text
    • http://gidaero.com/upload/fckeditor/file/24004071370.pdfIn PDF document text
    • http://faceconnects.com/ci/userfiles/files/75796637245.pdfIn PDF document text
    • http://alexandersorokolaw.com/customer/3/d/9/3d947ad6ce2568d98b832ccf5548371bFile/77505550294.pdfIn PDF document text
    • https://dom-titan.rs/files/xuvanotikisofugoj.pdfIn PDF document text
    • http://newtrichur.com/userfiles/file/mawutudomemuk.pdfIn PDF document text
    • http://jnejendomsdrift.dk/userfiles/file/30335083565.pdfIn PDF document text
    • http://botosani.ro/img/uploads/file/lunolotuwimevujomejum.pdfIn PDF document text
    • http://9y.bfage.com/upload/files/20210916055245.pdfIn PDF document text
    • http://www.shjkyq.com/up_files/FCK/file/vonivop.pdfIn PDF document text
    • http://nbc.com.vn/ckfinder/userfiles/files/7939321828.pdfIn PDF document text
    • https://feedproxy.google.com/~r/skout/mBVl/~3/LPIa9PGmDLg/uplcv?utm_term=android+bottom+app+bar+menuPDF 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 4

Files carved from inside the sample during analysis.

FilenameKindSourceSize
font_00_sfnt_off0000cba8.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xCBA8 17584 bytes
SHA-256: d1579f5eb3cc5a157a830ecd4b39c2b9c498e3cd494664d512d49397ffe255d9
font_01_sfnt_off0000fa30.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xFA30 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
font_02_sfnt_off00011247.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x11247 10560 bytes
SHA-256: 0c36a4a63fa6969c2d37ec0db223d07af5489e59978dcccbfdd99e2add1a5f7a
font_03_sfnt_off00012a13.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x12A13 17240 bytes
SHA-256: 05bb1c3f5f6696b8f2dd16d280a09f1c6656ebef8201447c5c1f6c23d37863f3