Malicious PDF — malware analysis report

Static analysis result for SHA-256 4d69801beb5b8b4e…

MALICIOUS

PDF

77.6 KB Created: 2021-09-30 12:46:44 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3)
MD5: a31fd295ad985f2b3f06e3a6b7e31c43 SHA-1: 51b76f41a70fa65bb55f46a5733dabb35526146f SHA-256: 4d69801beb5b8b4e5dd1be996eec4384a42373c6f3d8e5663ca433dbbc7c7424
156 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment

The sample was flagged by ClamAV and an ML classifier as malicious. It contains a link farm with numerous URLs pointing to potentially compromised websites or disposable hosting, indicating an attempt to redirect users to malicious content. The presence of external URI heuristics and the PDF_SEO_DISPOSABLE_LINK_FARM rule further support this attack pattern.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9955

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
  • PDF link farm points to compromised-WordPress upload storage medium PDF_COMPROMISED_CMS_UPLOAD_LINK_FARM
    PDF contains multiple clickable links, across many distinct hosts, whose targets are random-slug files parked in the upload directories of vulnerable WordPress form plugins (FormCraft, Super Forms). This is the hallmark of the 'free document/template' SEO phishing PDF family, which ranks for search queries and routes users into payload/redirect chains hosted on compromised sites. The PDF itself carries no exploit — the risk is the linked destinations.
  • 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://inwebjor.ru/uplcv?utm_term=android+18+pron
    • http://wxhsbl.com/ckfinder/userfiles/files/20210930_154357.pdf
    • https://dazhonghua1688.com/ckfinder/userfiles/files/55697951996.pdf
    • http://lasantitosrestaurant.com/userfiles/file/66949201119.pdf
    • https://unosms.us/userfiles/file/fivopudowawumakogaxas.pdf
    • http://koreaseowon.com/ckupload/files/zuvujepo.pdf
    • https://123natura.com/stockages/files/zufirezewid.pdf
    • https://masini-de-ambalat.ro/images/userfiles/mogebuzojomefigobozi.pdf
    • http://ytovietnam.net/ckfinder/userfiles/files/fetekabaf.pdf
    • http://vinacafe-dalat.com/Images_upload/files/dojibekeparuvifibuzav.pdf
    • http://www.examnotice.in/uploads/files/74309963840.pdf
    • http://bascobrunswick.com.au/wp-content/plugins/formcraft/file-upload/server/content/files/16149412492a91---vajojonukidupibosamomozo.pdf
    • https://cncostruzioni.com/userfiles/file/noguta.pdf
    • http://www.jokilaaksonratsastajat.fi/file/gatojejafirenedir.pdf
    • http://vonschickenconcord.com/uploads/files/kaxamewigufo.pdf
    • https://www.idd.no/ckfinder/userfiles/files/82987981382.pdf
    • https://www.cdscabling.co.uk/wp-content/plugins/formcraft/file-upload/server/content/files/1614c4f8ed7844---92232892857.pdf
    • https://orkhaconstruction.com/wp-content/plugins/super-forms/uploads/php/files/jnapid5ppt77ma5dmme6vipv7a/ribawisakutodazuviko.pdf
    • http://fkm-lux.by/var/upload/file/goxujexubadipizojewo.pdf
    • https://jaunimodienos.lt/wp-content/plugins/super-forms/uploads/php/files/asth5ao3ovcv8k1kopcja5erqc/xebegokefalinip.pdf
    • https://gastrotest.co/ckfinder/userfiles/files/49642869526.pdf
    • http://an-ocn.ru/ckfinder/userfiles/files/28283074502.pdf
    • https://aguiapromocional.com.br/wp-content/plugins/formcraft/file-upload/server/content/files/16149e99f21f76---14330885198.pdf
    • http://youngdongtec.com/userfiles/file/33120609792.pdf
    • http://www.w3.org/1999/02/22-rdf-syntax-ns#
    • http://purl.org/dc/elements/1.1/
    • http://ns.adobe.com/pdf/1.3/
    • http://ns.adobe.com/xap/1.0/
    • http://ns.adobe.com/xap/1.0/mm/
    • http://ns.adobe.com/xap/1.0/rights/
    • http://dejavu.sourceforge.net
    • http://dejavu.sourceforge.net/wiki/index.php/License

Extracted artifacts 4

Files carved from inside the sample during analysis.

FilenameKindSourceSize
font_00_sfnt_off0000b3da.bin
63b418583730aeb8df2e107923163ace96f97d73dadcecf99a461f5d75daed64
pdf-font-stream PDF embedded font (sfnt) at offset 0xB3DA 10020 bytes
font_01_sfnt_off0000ca23.bin
ec698e922318e948f107b413cd22f80925b80d3409263805066ef88403f83e4f
pdf-font-stream PDF embedded font (sfnt) at offset 0xCA23 19204 bytes
font_02_sfnt_off0000f9e1.bin
9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
pdf-font-stream PDF embedded font (sfnt) at offset 0xF9E1 16792 bytes
font_03_sfnt_off000111f2.bin
64af0185a2beffa7382febdf957b2ddd2015d3985e5bc97cf8ad64f3c2914973
pdf-font-stream PDF embedded font (sfnt) at offset 0x111F2 16060 bytes