Malicious PDF — malware analysis report

Static analysis result for SHA-256 c11ba16e4abdb411…

MALICIOUS

PDF

82.8 KB Created: 2021-10-10 02:16:04 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-11-25
MD5: 4c265033e9f456cac100e6df5808180e SHA-1: 2e175add9c59322815d2a95b8cee9f802e9fed3c SHA-256: c11ba16e4abdb411ea360a8178b9cf95b2f8fb0c24f433df67cb80401d5825dd
126 Risk Score

Malware Insights

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

The PDF was flagged by a machine learning classifier and ClamAV as malicious, specifically as a phishing trojan. Heuristics indicate it functions as a link farm, with numerous embedded URLs pointing to distinct domains, likely to obscure the final malicious destination. The presence of many unknown reputation URLs supports this assessment.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9833

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://retailpark.bg/uploads/wysiwyg/files/31014414175.pdf In PDF document text
    • http://praguynakorn.com/praguynakorn/picture/datapro/files/44882459667.pdfIn PDF document text
    • http://cerritos.songhakbbq.com/uploads/files/71227816033.pdfIn PDF document text
    • http://www.premiumimport.nl/ckfinder/userfiles/files/tedujadososi.pdfIn PDF document text
    • https://equipelec.fr/ckfinder/userfiles/files/bokijovasofad.pdfIn PDF document text
    • https://alperbehang.nl/userfiles/file/sulideput.pdfIn PDF document text
    • https://ecodiagnost.com/ckfinder/userfiles/files/51405240269.pdfIn PDF document text
    • http://www.vnos.vn/app/webroot/uploads/files/66641492015.pdfIn PDF document text
    • https://dcimx.com/files/43905245400.pdfIn PDF document text
    • https://weddingitaly.jp/images/file/vivuzebavisalijerigu.pdfIn PDF document text
    • http://studioambienteterritorio.it/userfiles/files/fosupufakufekuv.pdfIn PDF document text
    • http://am-assets.com/aom/magnolia/userfiles/file/81129521699.pdfIn PDF document text
    • https://jazykovytabor.topenglish.sk/app/webroot/gallery/files/jonuwi.pdfIn PDF document text
    • http://hissekurban.com/resimler/files/zemijigifug.pdfIn PDF document text
    • http://rioairporttransfer.com/ckfinder/userfiles/files/32022386969.pdfIn PDF document text
    • http://babijie.com/upload_fck/file/2021-10-9/20211009122231768464.pdfIn PDF document text
    • https://masterpieces-mallorca.com/wp-content/plugins/super-forms/uploads/php/files/59e08ca65f77e11365c781b92fed59fb/26844295344.pdfIn PDF document text
    • http://humanitool.ru/userfiles/file/67472982987.pdfIn PDF document text
    • http://futureinfashion.com/ckfinder/userfiles/files/42394702.pdfIn PDF document text
    • http://klhl.com/userfiles/file/50901600122.pdfIn PDF document text
    • https://novitas.ro/files/pijulubaredanesar.pdfIn PDF document text
    • https://skywaytravelandholidays.com/ckfinder/userfiles/files/regimifopakefevo.pdfIn PDF document text
    • http://eske.hu/wp-content/plugins/formcraft/file-upload/server/content/files/16160cfbe36aa8---21466596464.pdfIn PDF document text
    • https://podimercrm.com/img/files/vokarideduguvewepo.pdfIn PDF document text
    • http://aarogyamedico.com/userfiles/file/zexorixapubovapupofu.pdfIn PDF document text
    • http://notar-frings.de/userfiles/file/xeniluwaxodemavutef.pdfIn PDF document text
    • https://alutat.com/data/file/30702142793.pdfIn PDF document text
    • https://feedproxy.google.com/~r/1eyvgo/aqOO/~3/6naE_Nh8_CY/uplcv?utm_term=maths+crossword+with+answers+for+class+10PDF 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_off0000dbcd.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xDBCD 18756 bytes
SHA-256: 848cb82653be550da489af32c061309e350791e060a2e6190c2b720f7d5e92ad
font_01_sfnt_off00010c1f.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x10C1F 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
font_02_sfnt_off00012436.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x12436 10824 bytes
SHA-256: 97e041bd15f32a79ebdf33dcf9d3cc3e97ffc387ce1ba18920906cd5310e669f