Malicious PDF — malware analysis report

Static analysis result for SHA-256 a4b38d83ef753450…

MALICIOUS

PDF

81.6 KB Created: 2021-09-07 13:31:07 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-10-12
MD5: b75408a4b42c8f64b8cde28039f68a8a SHA-1: 0f386d2c8eefa925e0bbcb7dd64bb344dbf8d96e SHA-256: a4b38d83ef753450bfc1f515c4c6fc4711e78fb0b4b2f51e18e3cea8de65cd5a
156 Risk Score

Malware Insights

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

The PDF contains numerous links, many pointing to compromised websites or disposable hosting, indicating a link farm designed to redirect users to malicious content. ClamAV detected this file as Pdf.Phishing.Trojan, and ML classification strongly supports its malicious nature. The presence of multiple external URIs and link farms suggests an attempt to lure users to phishing sites or download further malware.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9974

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://pixomot.ru/uplcv?utm_term=tense+sequence+in+english+grammar+pdf PDF link annotation
    • http://dezis.ru/uploads/files/fudum.pdfIn PDF document text
    • http://e-skala.pl/userfiles/file/zuxuwinamuxisanif.pdfIn PDF document text
    • http://samuiluxurytravel.com/Uploads/file/79822488880.pdfIn PDF document text
    • http://www.elsecretodelolivo.com/wp-content/plugins/formcraft/file-upload/server/content/files/1608d5eff89d51---gurodita.pdfIn PDF document text
    • http://relatives-united.com/clients/75139/File/donowitujas.pdfIn PDF document text
    • https://www.dartmusicfestival.co.uk/wp-content/plugins/super-forms/uploads/php/files/30b50b7f7e4ca86a02284d122e9eba30/51990373468.pdfIn PDF document text
    • https://afgventuregroup.com/cfiles/file/foxukixogugesawul.pdfIn PDF document text
    • https://greenfuturevietnam.com/Upload/files/38312873959.pdfIn PDF document text
    • http://yung-shun.com/userfiles/file/zubukokirolekizusugagene.pdfIn PDF document text
    • https://www.inter-tube.co.uk/wp-content/plugins/super-forms/uploads/php/files/ab2a79440dd33e8e2cca726b1e0e42e5/34130750241.pdfIn PDF document text
    • https://diedacorporation.net/freesiafiles/file/xebijarijukugiwaxobonipif.pdfIn PDF document text
    • http://yalciniskele.com/imgup/file/robejorulagemuwax.pdfIn PDF document text
    • http://limpiasol.com/wp-content/plugins/formcraft/file-upload/server/content/files/1606d56e126c17---xamujiveguwegoneluf.pdfIn PDF document text
    • http://admio.ru/wp-content/plugins/formcraft/file-upload/server/content/files/160a14375af807---59673787521.pdfIn PDF document text
    • https://shrmivirtual.org/wp-content/plugins/super-forms/uploads/php/files/009b71692d52c4609ea784b88f9064d1/xaxitituk.pdfIn PDF document text
    • https://caravanandre.it/wp-content/plugins/super-forms/uploads/php/files/702b22e7e1288b447a535ec94f07fc4c/pesaxosuzejamexus.pdfIn PDF document text
    • https://tavio.ru/files/file/zaxat.pdfIn PDF document text
    • https://www.eecpowerindia.com/codelibrary/ckeditor/ckfinder/userfiles/files/94281679026.pdfIn PDF document text
    • http://sun-eko.eu/files/file/pemasisezuxaj.pdfIn PDF document text
    • http://www.ausafrica.co.za/wp-content/plugins/formcraft/file-upload/server/content/files/1606cfdca4331a---35411498417.pdfIn PDF document text
    • http://n2nnetworks.com/files/others/fiwosogifukijomobopovabus.pdfIn PDF document text
    • http://hanart21.com/files/userfiles/file/kukapavokejipuzilov.pdfIn PDF document text
    • https://thesmithgrouphouston.com/wp-content/plugins/super-forms/uploads/php/files/23960dbab350d51d58384f67091b6561/20204051677.pdfIn PDF document text
    • http://gdaniec.com/upload/files/42499695774.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_off0000d943.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xD943 11056 bytes
SHA-256: d7a8ed9f39b3a34dc451490d4d7d7042148e137ff8af62de6ec1f74907536ddd
font_01_sfnt_off0000f234.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xF234 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
font_02_sfnt_off00010a46.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x10A46 17808 bytes
SHA-256: 15cc3a2cdd5ace75842d34d4b80fd035bbac6250b1914e1fd8b56189dacdf799