Malicious PDF — malware analysis report

Static analysis result for SHA-256 87a74e537f4798ce…

MALICIOUS

PDF

81.6 KB Created: 2021-09-11 21:45:18 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-11-02
MD5: beaec1f76e3ad6c62d6f420b55a8290c SHA-1: 7b51d4c153b4947c223c6972418154c6e8d9a163 SHA-256: 87a74e537f4798ce846a9ada3ad1ad1e8c2fdf5bcba4dce84545942fc6bb3ba3
96 Risk Score

Malware Insights

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

The PDF contains a link farm with numerous URLs pointing to compromised CMS upload directories, as indicated by the 'PDF_COMPROMISED_CMS_UPLOAD_LINK_FARM' and 'PDF_SEO_DISPOSABLE_LINK_FARM' heuristics. The ML classifier also flagged this PDF as malicious with high confidence. These links likely serve as a distribution point for malicious content or phishing lures.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9975

Heuristics 5

  • 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 http://studiotecnicodambra.eu/userfiles/files/47922031478.pdf In PDF document text
    • http://mountmedpharmacy.co.za/wp-content/plugins/formcraft/file-upload/server/content/files/161388e5235a02---xugarinufivatibelenebu.pdfIn PDF document text
    • https://gemma.lucien-sv.info/uploads/files/61370d32569b3.pdfIn PDF document text
    • http://cleannshieldflorida.com/wp-content/plugins/super-forms/uploads/php/files/196d71c5b39d084304646d46aaa4b331/vamipoviwadajiluboniduxil.pdfIn PDF document text
    • https://moniimpex.com/wp-content/plugins/formcraft/file-upload/server/content/files/161317a13bd786---mawaxuwefi.pdfIn PDF document text
    • https://saintarseny.ca/sites/saintarseny.ca/files/file/51034011425.pdfIn PDF document text
    • https://dalyanestate.com/userfiles/file/65699994105.pdfIn PDF document text
    • http://realtor-madrid.com/uploades/fckeditorfile/91315659459.pdfIn PDF document text
    • https://aspaeng.com/files/image/files/benuduzagejilabudon.pdfIn PDF document text
    • http://polipadel.com/userfiles/file/24778352727.pdfIn PDF document text
    • http://www.rajpuc.pl/pics/file/32876939293.pdfIn PDF document text
    • http://polaryachtmanufactory.com/res/wysiwyg/file/gajelomomixisemanurevige.pdfIn PDF document text
    • https://www.ikedatosou.com/wp-content/plugins/formcraft/file-upload/server/content/files/1612f18ab6ae43---xedagumixivirobagizamepa.pdfIn PDF document text
    • https://lingchuanfloor.com/app/webroot/userfiles/files/13923556625.pdfIn PDF document text
    • http://mylodge-naoshima.com/images/blog/file/39106471028.pdfIn PDF document text
    • https://btegypt.com/file/21068080062.pdfIn PDF document text
    • https://thuaphatlaihanoi.net/uploads/files/lizuv.pdfIn PDF document text
    • https://freshchannels.com/home/sites/freshchannels/public_html/ckfinder/userfiles/files/35743118843.pdfIn PDF document text
    • https://turkihale.com/userfiles/file/In PDF document text
    • http://homokkepek.hu/editor_up/96506902621.pdfIn PDF document text
    • https://feng-shuiworld.com/userfiles/file/filinosugotiwegutupaf.pdfIn PDF document text
    • http://angelofthewinds.net/ckfinder/userfiles/files/molananepatudidede.pdfIn PDF document text
    • http://decom.pro/admin/ckfinder/userfiles/files/migawo.pdfIn PDF document text
    • http://specialcats.nl/media/files/82595913969.pdfIn PDF document text
    • http://business-plan-capalpha.eu/mbp/upload/images/images/upload/ckfinder/jejosora.pdfIn PDF document text
    • https://feedproxy.google.com/~r/skout/mBVl/~3/6naE_Nh8_CY/uplcv?utm_term=samantha+x+heroesPDF 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_off0000dc01.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xDC01 17524 bytes
SHA-256: 9913546394b0d421e08a16b15768656cde7a7771061150b986eb7aa324d034ad
font_01_sfnt_off0001094b.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x1094B 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
font_02_sfnt_off00012162.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x12162 10412 bytes
SHA-256: 02cf4e5a85da29a57ef9dc9d3453cf9f15b7b155d21f4f84a6a4289918b3fc3c