Malicious PDF — malware analysis report

Static analysis result for SHA-256 8f8f5a00bff0842d…

MALICIOUS

PDF

68.5 KB Created: 2021-09-27 14:25:29 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3)
MD5: bda404b1fa949daa6105c69c973c3c0f SHA-1: 84fbbfe266892bac4e5b68ce1df4c1e0302cdacd SHA-256: 8f8f5a00bff0842d3a3843d70abba53080d71763f245c2048403188f4c56e187
156 Risk Score

Malware Insights

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

The PDF contains numerous embedded URLs, many of which point to disposable hosting or compromised CMS uploads, indicating a link farm designed to redirect users. The ML classifier and ClamAV detection strongly suggest malicious intent, likely for phishing or malware delivery. The presence of multiple PDF link farm heuristics reinforces this assessment.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9951

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://1snrpaulista.com.br/ckfinder/userfiles/files/rupazidorejijanen.pdf
    • http://sissonne.hu/editor_up/guburamotabidafusewupege.pdf
    • http://xpeedon.net/userfiles/file/20210902140850.pdf
    • http://jinshi66.com/uploadfiles/files/lanamowajirolowarurabe.pdf
    • http://kssi.ir/public/userfiles/file/40791530272.pdf
    • https://dimensionshoppe.com/alpha/ckfinder/userfiles/files/milebilowipa.pdf
    • https://thuhuonglacquer.com/uploads/news_file/minave.pdf
    • http://www.wallisandemmanuel.com/wp-content/plugins/formcraft/file-upload/server/content/files/1614b94408c8bd---wajirovonubukosifaxamag.pdf
    • http://luatsugiadinhviet.com/upload/ck/files/novotalesijulazo.pdf
    • http://infinijewelry.com/userfiles/file/gabologefusibuvexafawodux.pdf
    • http://jj-metals.com/userfiles/file/2021092515434973499.pdf
    • http://cke.hk/userfiles/xanemiwul.pdf
    • http://di-tech.kr/fckeditor/userfiles/file/xokerupaseboxob.pdf
    • https://varida-tech.com/ckfinder/userfiles/files/20160504730.pdf
    • http://asijskepotraviny.cz/files/file/97511262915.pdf
    • http://oneself.pro/wp-content/plugins/formcraft/file-upload/server/content/files/16150a4b0292fe---5098964629.pdf
    • https://mygamedaysports.com/wp-content/plugins/super-forms/uploads/php/files/4841bb0f46e0fc747e6772fb10f1279b/xiwigoxunamasugilutenibag.pdf
    • http://igs.compcierge-asia.com/ckfinder/userfiles/files/sexezujovu.pdf
    • http://www.ausafrica.co.za/wp-content/plugins/formcraft/file-upload/server/content/files/1614eff31b3219---kagasijuzurefuzulotu.pdf
    • http://biosystech.com/pdsFck/file/fewusanenoxofenifi.pdf
    • http://pvvc.cz/files/87145959647.pdf
    • http://triumphtoday.org/wp-content/plugins/formcraft/file-upload/server/content/files/161408bff7c62f---xezevazipafezetatoveboti.pdf
    • http://sbkf.org/files/files/demiwo.pdf
    • https://arendic.cl/files/givazu.pdf
    • https://feedproxy.google.com/~r/Uplcv/~3/3vuEKuznOb8/uplcv?utm_term=skilltwins+2+apk+download
    • 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 3

Files carved from inside the sample during analysis.

FilenameKindSourceSize
font_00_sfnt_off0000afd4.bin
ed8613714220a88eae34c7b3c56aeb63aa8f365548429c1b1456d141b0801522
pdf-font-stream PDF embedded font (sfnt) at offset 0xAFD4 14608 bytes
font_01_sfnt_off0000d462.bin
4f6b6f93f6b4bf10f6510614a4a05307319da6a4de82fb029b5e47c881b9d732
pdf-font-stream PDF embedded font (sfnt) at offset 0xD462 10524 bytes
font_02_sfnt_off0000ec82.bin
9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
pdf-font-stream PDF embedded font (sfnt) at offset 0xEC82 16792 bytes