Malicious PDF — malware analysis report

Static analysis result for SHA-256 5cffeaa0cdbdde47…

MALICIOUS

PDF

77.0 KB Created: 2021-09-24 12:32:36 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-11-24
MD5: 3e95099eccc1fc9a595bd03d91ff77f2 SHA-1: 80326bcee1c142b4ac0059e98e88da65c52431b1 SHA-256: 5cffeaa0cdbdde47c9d57782dc2088213264c5abd7f7baadd1b0dd69d182f946
126 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment

The sample was flagged by ML and ClamAV as malicious, with heuristics indicating it functions as a link farm on disposable hosting. While no scripts were directly extracted, the PDF structure and numerous embedded URLs suggest an attempt to redirect users to potentially malicious sites, aligning with phishing or malware distribution tactics. The presence of multiple unknown URLs indicates a broad campaign.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9953

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 http://ventss.ru/userfiles/files/90312331435.pdf In PDF document text
    • http://hotelbelleepoque.bg/userfiles/file/9941519961.pdfIn PDF document text
    • https://www.iieng.org/editor/ckfinder/userfiles/files/juxefomenerepubibaj.pdfIn PDF document text
    • http://mbeautyconcept.com/upload/content_images/file/75478293251.pdfIn PDF document text
    • http://slenderclub.cz/ckfinder/userfiles/files/66770824170.pdfIn PDF document text
    • https://interior-mark.com/ckfinder/userfiles/files/84947305142.pdfIn PDF document text
    • https://kisikana.hr/UserFiles/files/lozibomokuzagezosuja.pdfIn PDF document text
    • http://balmybnb.com/t/tutorfirm/uploads/ck/files/biromidu.pdfIn PDF document text
    • http://gearcon-eng.com/file_media/file_image/file/40012820050.pdfIn PDF document text
    • https://biharlokmanch.org/userfiles/file/kizop.pdfIn PDF document text
    • https://leise.ru/admin/ckfinder/userfiles/files/54340520157.pdfIn PDF document text
    • http://macierz-grodziec.org/files/file/60916777565.pdfIn PDF document text
    • http://beccaro.it/userfiles/files/94377861537.pdfIn PDF document text
    • https://arab-hams.com/Ups/files/zadumawo.pdfIn PDF document text
    • https://www.ciabrini-immobilier.com/wp-content/plugins/super-forms/uploads/php/files/3havvs871tbqaj4ajr0fkj98ic/fiposabavojaxetefar.pdfIn PDF document text
    • http://27derajat.com/assets/ckfinder/core/connector/php/uploads/files/tiginufosovumafigi.pdfIn PDF document text
    • http://helderlive.nl/ckfinder/userfiles/files/larejafatuvixera.pdfIn PDF document text
    • http://tokstar.com/_UploadFile/Images/file/35137747303.pdfIn PDF document text
    • http://re-media.ru/foto/ck/files/14669217231.pdfIn PDF document text
    • https://angkalaris.com/contents/files/pugadaje.pdfIn PDF document text
    • http://jmk.kr/ckfinder/userfiles/files/21904449847.pdfIn PDF document text
    • http://goksirkrupskimlyn.pl/img/upload/files/53906123815.pdfIn PDF document text
    • http://wsm.hk/images/uploadfiles/file/memezosefabufazuwumefed.pdfIn PDF document text
    • https://feedproxy.google.com/~r/1eyvgo/aqOO/~3/DOqCt-cVA4I/uplcv?utm_term=my+android+keyboard+suddenly+changedPDF 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_off0000c6bc.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xC6BC 17780 bytes
SHA-256: dcd86aa660e1a33f00e993030b23b7eb6b0f89ce00e19eb704da2d94f305ad6d
font_01_sfnt_off0000f53f.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xF53F 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
font_02_sfnt_off00010d56.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x10D56 10988 bytes
SHA-256: fce2b264da4fa37a4be981f3bc0b886985567275dabd47c873fb5fe29982090a