Malicious PDF — malware analysis report

Static analysis result for SHA-256 b3954eeef22217bb…

MALICIOUS

PDF

98.1 KB Created: 2021-07-27 09:48:24 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-09-13
MD5: 7f08a5c391645d5663a8fc3a36c0a08c SHA-1: dd81cc16339a87a485017bc9fd73a7770114fe86 SHA-256: b3954eeef22217bb27536bd70ffd10a2da474f9b331f4c961229e9e1f23d752f
164 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment T1059.007 JavaScript

The sample is a PDF containing embedded JavaScript and a large number of external links. Several heuristics indicate that these links are part of a link farm, with some pointing to compromised WordPress upload directories, suggesting a phishing or malware distribution scheme. The ML classifier and ClamAV detection strongly indicate malicious intent.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9996

Heuristics 7

  • ClamAV: Pdf.Phishing.Trojan-d2528dad23a95d95-d2528dad23a95d95-10044376-0 critical CLAMAV_DETECTION
    ClamAV detected this file as malware: Pdf.Phishing.Trojan-d2528dad23a95d95-d2528dad23a95d95-10044376-0
  • 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.
  • Embedded JS stream low PDF_JS
    PDF references a /JS stream. Generic JavaScript is common in benign forms; specific dangerous APIs are scored by separate rules.
  • 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://master-sign.ru/ckfinder/userfiles/files/51347567844.pdf In PDF document text
    • https://quickonboarding.com/wp-content/plugins/super-forms/uploads/php/files/d987058fca966de229f981f692b6219a/baputoxezigixolivopaw.pdfIn PDF document text
    • https://metroguards.com.au/wp-content/plugins/formcraft/file-upload/server/content/files/160bba9c41f6e7---86484350376.pdfIn PDF document text
    • https://fentesmakina.com/paket/upload/files/80283274582.pdfIn PDF document text
    • http://smeclassof1987reunion.com/clients/37165/File/17233539360.pdfIn PDF document text
    • https://www.jscorporation.co.in/wp-content/plugins/formcraft/file-upload/server/content/files/160a662e2c4e92---pageviniluwozewulujaso.pdfIn PDF document text
    • https://soudurelauziere.com/upload/editor/file/55060527839.pdfIn PDF document text
    • https://aawyx.com/sites/default/imageuser/file/34105156921.pdfIn PDF document text
    • https://beatmuellerfoto.ch/userfiles/files/98110800749.pdfIn PDF document text
    • http://viaterrestre.com.br/wp-content/plugins/formcraft/file-upload/server/content/files/1606cbb9983230---66709174379.pdfIn PDF document text
    • https://ctapigroup3.com/contents//files/zibaxurikuxumasex.pdfIn PDF document text
    • https://saraelv.no/wp-content/plugins/formcraft/file-upload/server/content/files/160874d76a5144---55283298725.pdfIn PDF document text
    • http://ecompletecontact.com/ckfinder/userfiles/files/zilexagibasininepinul.pdfIn PDF document text
    • http://burningspearmarketplace.com/js/ckfinder/userfiles/files/vipixaxikejarumujaf.pdfIn PDF document text
    • http://yuhenganquan.com/userfiles/file/20210720201946_462972537.pdfIn PDF document text
    • http://www.skup.it/wp-content/plugins/formcraft/file-upload/server/content/files/16092786b39cb7---rebubudigufapinanusev.pdfIn PDF document text
    • https://feedproxy.google.com/~r/1eyvgo/aqOO/~3/GLLx1DTH0VQ/uplcv?utm_term=descargar+bbva+provincial+dinero+rapido+apkPDF 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_off000115e6.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x115E6 19312 bytes
SHA-256: 6d72bd27a1e37886ac6da5469d1388d40ce7a423b24e9453ca76e0bdb8e19a6f
font_01_sfnt_off00014783.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x14783 10892 bytes
SHA-256: 1522f14915f962a6386e5c71894e826df76256efcf24b660e26dbad9f0d5ee2c
font_02_sfnt_off0001606c.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x1606C 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1