Malicious PDF — malware analysis report

Static analysis result for SHA-256 8dbc93ad2be0c0e4…

MALICIOUS

PDF

71.1 KB Created: 2021-09-08 15:34:46 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-10-05
MD5: bacc5ea6781959705952f9da59df6f98 SHA-1: 66711d603cd811b868406b4a19408e11ad365449 SHA-256: 8dbc93ad2be0c0e43507c360a5ced1a4e7e29dfab3043e866b6bab564b42e5ca
156 Risk Score

Malware Insights

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

The PDF contains numerous embedded URLs, many of which point to compromised websites or disposable hosting, indicating a link farm designed to redirect users. The ML classifier and ClamAV detection strongly suggest malicious intent, likely phishing or malware distribution. The heuristic 'PDF_SEO_DISPOSABLE_LINK_FARM' confirms the nature of the links, and the presence of 'PDF_COMPROMISED_CMS_UPLOAD_LINK_FARM' suggests these links may lead to further malicious content.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9973

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=concrete+abstract+and+collective+nouns+worksheet PDF link annotation
    • http://www.sosonomo.com/ckfinder/userfiles/files/7644959007.pdfIn PDF document text
    • http://thevale.us/userimages/fabukaziki.pdfIn PDF document text
    • https://dodatnagarancija.com/userfiles/file/33439351039.pdfIn PDF document text
    • http://bookblog.kr/data/file/files/1347108322.pdfIn PDF document text
    • https://pre-www.bridge-academy.com/uploaded/ckeditor/files/43774823142.pdfIn PDF document text
    • http://bloemenwinkelindex.nl/images/uploads/bikusu.pdfIn PDF document text
    • https://areshin.ru/wp-content/plugins/super-forms/uploads/php/files/275551482634e884442717dba545b833/kagarolegaxakofumejeze.pdfIn PDF document text
    • http://sz-nuoyi.com/Upload/file/2021090411135624060.pdfIn PDF document text
    • https://popa.com.br/wp-content/plugins/super-forms/uploads/php/files/bf1043b8d102bbf6a589a7d5bcf378dd/zanajopajufefalufagewumag.pdfIn PDF document text
    • https://kes-stv.ru/wp-content/plugins/super-forms/uploads/php/files/3ff9de9986cf84cc2c6ebaa4f12c03bb/8585046724.pdfIn PDF document text
    • http://ingatlanfelugyelet.hu/uploads/file/53435666078.pdfIn PDF document text
    • http://old.bgk-meshkova.com/ckeditor/ckfinder/userfiles/files/91453570285.pdfIn PDF document text
    • http://denki-shonan.com/uploadsfile/xekirixebijovudebidoz.pdfIn PDF document text
    • http://kubablimel.pl/Image/files/kavodimubakemexiwaguw.pdfIn PDF document text
    • http://www.pilartangguh.com/file/36132568595.pdfIn PDF document text
    • https://rdsdealers.com/ckfinder/userfiles/files/lejesurubedubanamatu.pdfIn PDF document text
    • https://cobaltinc.org/userfiles/file/jesunetakiziwadirinev.pdfIn PDF document text
    • https://www.golaw.net/wp-content/plugins/formcraft/file-upload/server/content/files/161367f931c3e1---turefunanagapapijedasoke.pdfIn PDF document text
    • http://air-ned.com/uploads/files/safezekotutozumapos.pdfIn PDF document text
    • http://shinies.ru/img/lib/file/74506703548.pdfIn PDF document text
    • https://getracemirates.com/userfiles/files/87699657706.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_off0000b429.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xB429 10984 bytes
SHA-256: 7055c40e011bb2eb5e6942ead9a5b67524a07a536cd4c477e2ba949d8c6c421f
font_01_sfnt_off0000cdac.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xCDAC 16032 bytes
SHA-256: 9f1dd5c7512b1d503003a6b33162a5f93423e3be676ef2aa593ac3dd28989cc3
font_02_sfnt_off0000f6ab.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xF6AB 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1