Malicious PDF — malware analysis report

Static analysis result for SHA-256 8fbb8ccc674fe9c0…

MALICIOUS

PDF

76.3 KB Created: 2021-09-20 19:37:38 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3)
MD5: 90deee35f69349137c51439f742ce606 SHA-1: 6405e8db0faab77d24adc9b64769b88e70b834ba SHA-256: 8fbb8ccc674fe9c077f53b78deba1bfdf2143a73e0d92d95dfefc4618a16af1f
156 Risk Score

Malware Insights

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

The PDF file was flagged by a ML classifier and ClamAV as malicious, specifically as a phishing trojan. It contains a link farm pointing to compromised WordPress upload storage and other disposable hosting, suggesting an attempt to redirect users to malicious content. The presence of multiple external URIs and a link farm indicates a phishing or malware distribution attempt.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9908

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://vinaconexmec.vn/uploads/news_file/81139687753.pdf
    • http://pro-group.ru/userfiles/file/bowafosiserojujoke.pdf
    • https://nakipoglugroup.com/upload/ckfinder/files/kutusazemoroja.pdf
    • https://theurbanthinktank.com/files/vuraburanidavutitilulewu.pdf
    • http://fsanaq.com/upload/file/210903082138699470jrbbowtybflw.pdf
    • https://bilalyapidekorasyon.com/userfiles/file/69596308641.pdf
    • https://legend-chang.com/UserFiles/files/47844173228.pdf
    • https://chungangroup.com/uploads/files/202109200215004254.pdf
    • http://www.mariabeckmann.com/fotos/uploads/files/fonuzow.pdf
    • https://valserve.in/web/k/main_admin/ckfinder/userfiles/files/17682686122.pdf
    • https://millvalley.com/wysiwygfiles/file/58163967112.pdf
    • http://parbatsamajjapan.com/img/files/files/tisogabudebabagebabibokuf.pdf
    • http://www.peplex.it/wp-content/plugins/formcraft/file-upload/server/content/files/1613e17fbbaa05---81899422847.pdf
    • https://kujainspectors.com/candyticket/uploads/page_images/files/donezivisoziruzevelur.pdf
    • https://resonanceacteurs.nl/userfiles/file/22479721649.pdf
    • http://princeverma.in/uploads/files/84071493657.pdf
    • http://maekuangudomthara.com/ckfinder/userfiles/files/fejabamakatubekezotevazo.pdf
    • http://moveisgarciadigital.com.br/wp-content/plugins/formcraft/file-upload/server/content/files/1613dc2b02528e---nenukaloxe.pdf
    • http://pokebarslo.com/uploads/files/najudopaperu.pdf
    • https://mayersoffice.com/userfiles/file/vogitix.pdf
    • https://www.mybizwebsites.com/wp-content/plugins/formcraft/file-upload/server/content/files/1613906dea72fe---xukevofak.pdf
    • http://chaitraglaze.com/uploads/96360637356.pdf
    • http://www.ecvbrass.ch/user/web/file/takase.pdf
    • http://cafehinglung.com/uploads/files/defegid.pdf
    • https://shevtsov-art.com/uploads/files/nesitimurutupuvetumikikod.pdf
    • http://www.appsolutely.sg/wp-content/plugins/formcraft/file-upload/server/content/files/1613e5896d2079---murodagikazem.pdf
    • https://feedproxy.google.com/~r/Uplcv/~3/GLLx1DTH0VQ/uplcv?utm_term=youtube+to+download+apk
    • 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_off0000c76a.bin
8daa72f0511267082b9f1f096e893b9ab3b2ec5e0e9006eb009ba320b2b1adcd
pdf-font-stream PDF embedded font (sfnt) at offset 0xC76A 10424 bytes
font_01_sfnt_off0000df05.bin
9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
pdf-font-stream PDF embedded font (sfnt) at offset 0xDF05 16792 bytes
font_02_sfnt_off0000f717.bin
0eaf3839a0ac0e277ac3a28dd21968ada907159b8355a92ed29d93e5c1906263
pdf-font-stream PDF embedded font (sfnt) at offset 0xF717 17372 bytes