Malicious PDF — malware analysis report

Static analysis result for SHA-256 fd16fb31977e21b0…

MALICIOUS

PDF

70.7 KB Created: 2021-09-25 14:14:24 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-10-27
MD5: 2991caf8884e9775abb64c18cbfba135 SHA-1: c74f39c7514bbd05001ef53e6a7b106f80f5b90c SHA-256: fd16fb31977e21b0ea8512cfe205be143993a9b4ac19f85234064a71e299aa48
134 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment T1203 Exploitation for Client Execution

The sample is a PDF containing embedded JavaScript and a large number of external URIs, many of which are hosted on disposable domains. The ML classifier and ClamAV detection strongly indicate malicious intent, likely phishing or malware distribution. The embedded JavaScript and external links suggest an attempt to redirect the user to a malicious site for further exploitation.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9965

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://coretry.ru/uplcv?utm_term=how+to+restart+phone+without+password PDF link annotation
    • http://termosystem.pl/userfiles/file/37334797777.pdfIn PDF document text
    • http://www.leposeur.fr/site/upload/ckfinder/files/21065455146.pdfIn PDF document text
    • http://www.fdconsult.qa/public/uploads/cms_files/91209358035.pdfIn PDF document text
    • http://ambvet-trefontane.eu/userfiles/files/68855606310.pdfIn PDF document text
    • https://undergroundtakeout.com/userfiles/file/sojeriza.pdfIn PDF document text
    • https://worldpigment.com/image/upload/File/fofim.pdfIn PDF document text
    • http://prosquash.by/data/42869687462.pdfIn PDF document text
    • http://ljjxmining.com/uploadfile/file///2021090821365414.pdfIn PDF document text
    • http://vakantie-noordlimburg.nl/ckfinder/userfiles/files/fidemizetubinawatosovav.pdfIn PDF document text
    • http://casms.org/atts/news-files/file/nawitumipes.pdfIn PDF document text
    • http://extintoresorigen.com/images/editor/90689568696.pdfIn PDF document text
    • http://mgocsm.in/userfiles/file/88964404239.pdfIn PDF document text
    • http://extintoresorigen.com/images/editor/ridivezonepova.pdfIn PDF document text
    • https://carthink.org/wp-content/plugins/formcraft/file-upload/server/content/files/161456c11bf3f4---bozakoladadarojiz.pdfIn PDF document text
    • https://sensormaticltd.com/app/templates/js/ckfinder/userfiles/files/53434051875.pdfIn PDF document text
    • http://hamishehbaharcarpet.com/My_Project/Hamishe_bahar/ahar_img/files/38951210207.pdfIn PDF document text
    • https://www.mobytec.com.br/mobytec/wp-content/plugins/formcraft/file-upload/server/content/files/1614ef3fbc2cd5---63743455637.pdfIn PDF document text
    • http://xn--9p4b29dncp2cc6y.net/upload/fckeditor/file/lobexisukituwexubejuvapam.pdfIn PDF document text
    • http://studiofantino.it/userfiles/files/tuviliponikujurapom.pdfIn PDF document text
    • https://ckmandarin.com/uploads/48564049573.pdfIn PDF document text
    • http://uro-medical.pl/zdjecia/fotki/file/doxis.pdfIn PDF document text
    • https://www.sahabatkeluargahomecare.com/wp-content/plugins/formcraft/file-upload/server/content/files/1613f945506460---lumuvamatabojokasidexiw.pdfIn PDF document text
    • http://natur-pet.cz/webpagebuilder/ckfinder/userfiles/files/72189756579.pdfIn PDF document text
    • http://orosweb.hu/ckfinder/userfiles/files/xovivana.pdfIn PDF document text
    • http://on-video.com/movies/movie_data/file/gejazelazojudig.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_off0000b1c8.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xB1C8 10620 bytes
SHA-256: ea23021c716889958d7ec2e9d887474fc8b30e7dfe496b3700b4eb7f3a796f9f
font_01_sfnt_off0000ca0a.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xCA0A 17088 bytes
SHA-256: 62745903d4238b19c6a890e5afb7f4e4f546fd96abf147648eafbd884813646b
font_02_sfnt_off0000f502.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xF502 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1