Malicious PDF — malware analysis report

Static analysis result for SHA-256 8af25318e766a896…

MALICIOUS

PDF

81.5 KB Created: 2021-09-23 06:29:04 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-10-26
MD5: 88b06fbadc7d2a89e736fb3a9b072a33 SHA-1: 8a383cd73bdf22b08ed9031c2021e69c23830264 SHA-256: 8af25318e766a8969e0caa7241c18e558bb62e8e4202a1be08cb406d263ac934
126 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment

The PDF file was detected as malicious by ClamAV and an ML classifier, indicating a high likelihood of malicious intent. It contains numerous embedded URLs, many of which are hosted on disposable domains, suggesting a link farm or phishing campaign. The presence of external URIs and the overall structure point towards an attempt to redirect users to malicious sites for further exploitation or credential harvesting.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9917

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://coretry.ru/uplcv?utm_term=animals+ringtone+app PDF link annotation
    • http://bckbytow.naszbip.pl/img/upload/files/2965258543.pdfIn PDF document text
    • https://essaidafm.com/uploads/FCK_files/file/butosakugulos.pdfIn PDF document text
    • https://callhfelectric.com/wp-content/plugins/formcraft/file-upload/server/content/files/16147c71b316b1---midag.pdfIn PDF document text
    • http://sanfrancescovet.com/userfiles/files/titezi.pdfIn PDF document text
    • https://niboparis.com/upload/fckeditor/files/mododupetovukodofodobuk.pdfIn PDF document text
    • https://theemperorsoldclothes.co.uk/wp-content/plugins/super-forms/uploads/php/files/mn2vlbjcqi4aq88v14dr4r1i13/16720687978.pdfIn PDF document text
    • https://lyna-garage.com/htdocs/cljr/data/files/dopadulukosawesosoz.pdfIn PDF document text
    • http://thietbianninh188.com/uploads/files/sazatulebovotobagufogukaf.pdfIn PDF document text
    • http://hai-bi.com/uploads/files/202109180012308599.pdfIn PDF document text
    • http://jsqnchem.com/upload/files/kolazune.pdfIn PDF document text
    • https://nisahanpin.com/calisma2/files/uploads/puborowumaxinuko.pdfIn PDF document text
    • https://tinhhoaxanh.vn/userfiles/file/33102902313.pdfIn PDF document text
    • https://www.huaikrachaohospital.go.th/assets/global/lib/ckfinder/userfiles/files/58335681781.pdfIn PDF document text
    • https://38e5bbdfe8be.gdziezjesc.info/userfiles/file/bixevaxufopo.pdfIn PDF document text
    • https://footballsod.com/images/ck-uploads/files/vunilerazigigukubekesojom.pdfIn PDF document text
    • http://ototavandosemesi.com/resimler/file/sutarujidinojutite.pdfIn PDF document text
    • http://dialog-seversk.ru/jsplugins/ckfinder/userfiles/files/68926127591.pdfIn PDF document text
    • https://turdv.ru/SITE/files/editor/file/rafejevizexikiworevotozu.pdfIn PDF document text
    • http://hzqljsj.com/images/upload/File/59030244195.pdfIn PDF document text
    • https://penzionradvanice.cz/res/file/43028162004.pdfIn PDF document text
    • http://thai-apsproducts.com/file_media/file_image/file/dadabefutujovoweku.pdfIn PDF document text
    • http://getdol.com/page_data/file/vupazinupazivusejesexego.pdfIn PDF document text
    • https://damiel.eu/userfiles/file/tigonotasadurapometugam.pdfIn PDF document text
    • http://clinicaveterinariabilancino.it/userfiles/files/rigataxidenezu.pdfIn PDF document text
    • https://luminex.pl/upload/file/kojabuf.pdfIn PDF document text
    • https://jfava.gemwareserp.com/userfiles/file/42718275056.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_off0000dc2d.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xDC2D 10576 bytes
SHA-256: c8b3e119a243549c360019ba66949e4347b8ca73bbf2ba8fec04501292f3cce2
font_01_sfnt_off0000f444.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xF444 17088 bytes
SHA-256: aff5308f2f88fafc0a768b899f75d71d5d0d57479b5c0608fd19e8357dcc3727
font_02_sfnt_off00012018.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x12018 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1