Malicious PDF — malware analysis report

Static analysis result for SHA-256 f8499adbde98eb0c…

MALICIOUS

PDF

90.2 KB Created: 2021-07-22 15:47:30 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-09-29
MD5: be9be5c5f1a910ada1d59555fbe45ac0 SHA-1: cc3e0e8c0eaa49604891586971962fff2a31db83 SHA-256: f8499adbde98eb0cb3760f3ff48a250900b73b72f4d144fe523f30f360fa8397
96 Risk Score

Malware Insights

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

This PDF document was flagged as malicious by an ML classifier. The file embeds a large number of external links characteristic of an SEO link farm, many hosted on compromised CMS upload directories. Specific URLs and indicators for this sample are listed in the indicators section.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9939

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 https://www.wikiwebagency.it/wp-content/plugins/super-forms/uploads/php/files/44bcfa554c5ee0c6b4e2f73930c35e58/52206476120.pdf In PDF document text
    • https://www.baptistenhardenberg.nl/wp-content/plugins/formcraft/file-upload/server/content/files/16099d9835f950---tiwotofufupomimifeji.pdfIn PDF document text
    • https://www.sidertest.it/wp-content/plugins/formcraft/file-upload/server/content/files/1607b74a0e227a---18630827677.pdfIn PDF document text
    • http://vtracauto.com/wp-content/plugins/formcraft/file-upload/server/content/files/1609c572691a27---lizezezazefofi.pdfIn PDF document text
    • https://sitebyside.ru/wp-content/plugins/super-forms/uploads/php/files/ab31247d3977b19f6032d0a8ce84d59b/gipesugizezimoxironoxe.pdfIn PDF document text
    • https://www.msolartop.cz/wp-content/plugins/formcraft/file-upload/server/content/files/16076836998138---64068407092.pdfIn PDF document text
    • http://audiomaster.se/wp-content/plugins/formcraft/file-upload/server/content/files/160ab4578d2232---pidaxaredewifomobolivu.pdfIn PDF document text
    • https://www.kngroup.com/wp-content/plugins/formcraft/file-upload/server/content/files/16091a76a7fab5---relarijutamilidizovirixi.pdfIn PDF document text
    • https://108pizza.pl/uploads/userfiles/files/vedabexuvedidiv.pdfIn PDF document text
    • http://jarosi.hu/files/file/timevuwikoleloseju.pdfIn PDF document text
    • http://limobebe.com/userfiles/files/bedadi.pdfIn PDF document text
    • http://kindervakantieweekdeurne.nl/wp-content/plugins/formcraft/file-upload/server/content/files/1607c34991dce6---86314697078.pdfIn PDF document text
    • https://encouragingmath.com/wp-content/plugins/super-forms/uploads/php/files/814eac14803a620e21430a4901cd946b/sufawaxupepikexalod.pdfIn PDF document text
    • https://alexandrapanayotou.com/web/images/static/file/zukivuvaledulereb.pdfIn PDF document text
    • http://careerhack.net/wp-content/plugins/formcraft/file-upload/server/content/files/16079fe22630b0---14269188974.pdfIn PDF document text
    • http://marthomaiticherukole.com/userfiles/file/61058311235.pdfIn PDF document text
    • http://www.multigacos.com/admin/uploaded/fck/file/xavizesirotuzixijuzu.pdfIn PDF document text
    • https://www.revistadefiesta.com/wp-content/plugins/formcraft/file-upload/server/content/files/1609cbdbe1c4fb---wefagajuwajijikikev.pdfIn PDF document text
    • https://honghow.com/ckfinder/userfiles/files/xavenub.pdfIn PDF document text
    • http://qboardapp.com/wp-content/plugins/super-forms/uploads/php/files/917d094cb31c4cc2b85774a13438b24e/kazobadomevegozinaxip.pdfIn PDF document text
    • https://aronabritcan.com/userfiles/file/57963308237.pdfIn PDF document text
    • http://whkmradio.com/userfiles/file/31188514218.pdfIn PDF document text
    • http://av-jet.ru/userfiles/file/93950515711.pdfIn PDF document text
    • http://www.nanodrywash.com/wp-content/plugins/formcraft/file-upload/server/content/files/1607bf68677218---gimopixosabi.pdfIn PDF document text
    • http://paymentsbusiness.ca/wp-content/plugins/formcraft/file-upload/server/content/files/160b095e107508---lubotixebugeregazegeri.pdfIn PDF document text
    • https://feedproxy.google.com/~r/Uplcv/~3/3vuEKuznOb8/uplcv?utm_term=march+21+2021+asteroidPDF 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_off0000fb05.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xFB05 18340 bytes
SHA-256: 11327f2b89122fe16e9e667a4955abb06114b9abc54ecde74d56703410971bb3
font_01_sfnt_off00012b35.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x12B35 10604 bytes
SHA-256: 787f9c922e8a29a0ece46d2558a8f23e604d74e5def3500c52d2616754bd14bc
font_02_sfnt_off000143b6.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x143B6 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1