Malicious PDF — malware analysis report

Static analysis result for SHA-256 bb6f598e55d2846c…

MALICIOUS

PDF

80.6 KB Created: 2021-09-24 01:32:59 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-11-25
MD5: fa57962759cebb4608a3e8ee7d96a23b SHA-1: a631d7ca47a37286c6bd772b41790a94efd2235d SHA-256: bb6f598e55d2846cd5452eb459ae8f63758e7068aa33642542cfa2f99d356911
164 Risk Score

Malware Insights

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

This PDF was flagged by a machine learning classifier and ClamAV as malicious, indicating it is likely a phishing or trojan delivery mechanism. The file contains a link farm pointing to multiple URLs, many of which are hosted on compromised CMS uploads, suggesting an attempt to disguise malicious content. The presence of a 'download' button heuristic further supports the lure-based attack pattern.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9968

Heuristics 7

  • 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.
  • Visual download / call-to-action button lure low SE_DOWNLOAD_BUTTON
    Document contains a call-to-action phrase ('Click here to download', 'Download Now', etc.) — low-signal unless other findings point to a malicious workflow
  • 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 http://www.nbrownies.com.br/wp-content/plugins/formcraft/file-upload/server/content/files/16143253a390a1---nilasijamaxoxov.pdf In PDF document text
    • http://investinwielkopolska.pl/application/lib/ckfinder/userfiles/files/9486414995.pdfIn PDF document text
    • https://cristiandellavedova.com/wp-content/plugins/super-forms/uploads/php/files/8f0e5b6e4f8dd6415abf764b5c20c5e4/4369124192.pdfIn PDF document text
    • http://londonjip.com/userData/board/file/9124854675.pdfIn PDF document text
    • http://cobansut.com/userfiles/file/xofopanogivukodunogotij.pdfIn PDF document text
    • https://mamap.in/ci/userfiles/files/11376503235.pdfIn PDF document text
    • http://ropesadventure.com/d/files/71534890136.pdfIn PDF document text
    • http://parzenica-bialka.pl/userfiles/files/8500019637.pdfIn PDF document text
    • https://greenbins.ca/ckfinder/userfiles/files/4157544227.pdfIn PDF document text
    • https://dongciao.com/uploads/files/202109031646491194.pdfIn PDF document text
    • http://climtech.com/files/files/95418818169.pdfIn PDF document text
    • http://nek.ua/wp-content/plugins/formcraft/file-upload/server/content/files/161407eeb005e5---54257470483.pdfIn PDF document text
    • http://studiosiriosrl.it/userfiles/files/27599129782.pdfIn PDF document text
    • https://cdmsig1.com/ckfinder/userfiles/files/nagijukujufiluxugexolom.pdfIn PDF document text
    • https://edusfera.pl/upload/file/3856520413.pdfIn PDF document text
    • http://cnwt.mgo.cool/upfile/files/2021/09/10/64880485557.pdfIn PDF document text
    • http://transportdiverse.com/uploads/files/66911154796.pdfIn PDF document text
    • http://greensquares.in/userfiles/file///45030751882.pdfIn PDF document text
    • https://www.notusweb.com.br/ckeditor/ckfinder/userfiles/files/sasuxu.pdfIn PDF document text
    • http://ooexperience.be/assets/Image/files/xuvoviwavapakinezu.pdfIn PDF document text
    • http://vitajeans.com/ckfinder/userfiles/files/48258356940.pdfIn PDF document text
    • https://charming-dc.com/uploads/files/202109041257113317.pdfIn PDF document text
    • https://feedproxy.google.com/~r/skout/mBVl/~3/6naE_Nh8_CY/uplcv?utm_term=ielts+reading+academic+pdf+2021PDF link annotation
    • 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_off0000d659.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xD659 17452 bytes
SHA-256: a6f3e1dba4392728b0056e0a880de67e8b20d322b5e623bee0ce0d058613baaa
font_01_sfnt_off0001038d.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x1038D 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
font_02_sfnt_off00011ba4.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x11BA4 11088 bytes
SHA-256: 4eb0f1d0fd2abe6066b350ed5b1e6ad1a37e1cd36c2ae827098b7693a12d8ad9