Malicious PDF — malware analysis report

Static analysis result for SHA-256 503774273248574a…

MALICIOUS

PDF

75.7 KB Created: 2021-06-20 19:45:08 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 4.8.7)
MD5: db9ff904403820db50f53175f4d5d939 SHA-1: 52667ea79674aee7e4278bf1bcb3d3fff1f2cd86 SHA-256: 503774273248574a79d099a61f4abbbe77412fbde1aa8834341beb0f1557aeb4
156 Risk Score

Malware Insights

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

The sample is a PDF file flagged as malicious by ClamAV and an ML classifier. It contains numerous links pointing to compromised websites, indicating a phishing or malware distribution attempt. The presence of PDF_SEO_DISPOSABLE_LINK_FARM and PDF_COMPROMISED_CMS_UPLOAD_LINK_FARM heuristics further supports this, suggesting the PDF is part of a link farm hosted on potentially compromised infrastructure.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9996

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://provisionsinternational.com/wp-content/plugins/formcraft/file-upload/server/content/files/160b0761b62d7a---nisokirujixi.pdf
    • http://www.cascinasorigherio.it/wp-content/plugins/formcraft/file-upload/server/content/files/1608f76f11a1f2---34309931452.pdf
    • http://vietxetai.com/wp-content/plugins/super-forms/uploads/php/files/646d79gpkmi1g4uk85r8qmfn5s/rajig.pdf
    • http://www.barankayalar.com.tr/wp-content/plugins/formcraft/file-upload/server/content/files/160a60e0d11503---natejinakitazuwamib.pdf
    • https://daismene.it/file/7991287121.pdf
    • http://poolprotektor.com/userfiles/file/10028798243.pdf
    • https://www.kadeavenue.com/wp-content/plugins/super-forms/uploads/php/files/b78031b4e5873abbd623f4e00f44c4ff/denidigumanaxonoli.pdf
    • https://www.qbuildsoftware.com/wp-content/plugins/super-forms/uploads/php/files/e3b423bf09300023571e2bcd5ec9427a/70550014716.pdf
    • https://extremetour74.ru/wp-content/plugins/super-forms/uploads/php/files/ca7c5d4a23483fcdce7ec764ffcbd622/73360013707.pdf
    • https://40parables.com/wp-content/plugins/super-forms/uploads/php/files/0f809db82f51428285150afc0c415789/zimugo.pdf
    • http://cohn-vossen.com/wp-content/plugins/formcraft/file-upload/server/content/files/1606d8a559630b---66830636830.pdf
    • https://forkidsvietnam.vn/wp-content/plugins/super-forms/uploads/php/files/q806pgf2j8kcbl2ui2iglfl85i/95791504443.pdf
    • http://smartcookieacademy.com/wp-content/plugins/formcraft/file-upload/server/content/files/160abf4bad20a5---90636397502.pdf
    • http://talleresjpg.es/img/file/sopur.pdf
    • http://mirembeestate.co.ug/wp-content/plugins/formcraft/file-upload/server/content/files/16077a8a8e25db---lujavekasofagapamif.pdf
    • https://www.elitelawnsolutions.co.uk/wp-content/plugins/super-forms/uploads/php/files/7u9c09ctqpq2fn8svrn4i1cb2m/54088401811.pdf
    • http://paulbwatkinslaw.com/customer/3/d/9/3d947ad6ce2568d98b832ccf5548371bFile/dupolitosanuxolama.pdf
    • http://www.ascendercorp.com/
    • http://www.ascendercorp.com/typedesigners.html
    • https://feedproxy.google.com/~r/1eyvgo/aqOO/~3/zMnd8XtcwSM/uplcv?utm_term=kgf+chapter+2+ki+ringtone
    • 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://scripts.sil.org/OFL
    • 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_off0000cb4b.bin
fe8a1e1db11de895b5b143ccb3473b2a9048b79347f67531f29e31a29514a5c6
pdf-font-stream PDF embedded font (sfnt) at offset 0xCB4B 5232 bytes
font_01_sfnt_off0000dd1e.bin
a36eee06fef6ce219692c4ec918276ac99413e4fd1e3666e4031624f9289d620
pdf-font-stream PDF embedded font (sfnt) at offset 0xDD1E 1800 bytes
font_02_sfnt_off0000e5ab.bin
a886d0f922d0a8a62993d6d8647e0b72bdef6479699e336362cbf8bc02e73d09
pdf-font-stream PDF embedded font (sfnt) at offset 0xE5AB 11252 bytes
font_03_sfnt_off00010c29.bin
8c1e3298cb301b6aa2c2aeff0a89e1cafee6626e56d5ffa98ad52a7598c40df9
pdf-font-stream PDF embedded font (sfnt) at offset 0x10C29 16168 bytes