Malicious PDF — malware analysis report

Static analysis result for SHA-256 9bbd0e4b9cae0041…

MALICIOUS

PDF

83.3 KB Created: 2021-09-16 02:14:42 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-10-07
MD5: 14db97b8ab86ed9a6924a1b31dd1e50b SHA-1: 4891416b30cc40a8fab266c4c3c6adcaa8483165 SHA-256: 9bbd0e4b9cae00415548d8a6c0dd9bd51a5eb54fd00b5c15300bdba630921de0
96 Risk Score

Malware Insights

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

The PDF file contains a link farm with numerous URLs, many of which point to compromised WordPress upload directories. The ML classifier strongly indicates maliciousness. The presence of these links suggests an attempt to redirect users to potentially harmful content or to manipulate search engine rankings.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9964

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://chcial.ru/uplcv?utm_term=top+10+games+for+android+in+world PDF link annotation
    • http://www.siscard.com/wp-content/plugins/formcraft/file-upload/server/content/files/1612f72c680fcb---dololuvake.pdfIn PDF document text
    • http://www.rec39.ru/wp-content/plugins/super-forms/uploads/php/files/2c23e89c9d2adec300f36b0876aab373/kobonupexegika.pdfIn PDF document text
    • https://honghow.com/ckfinder/userfiles/files/21971245659.pdfIn PDF document text
    • http://fine-trading-knotwork.de/uploads/media/62488049329.pdfIn PDF document text
    • https://suncables.co/images/file/5054014683.pdfIn PDF document text
    • https://fzclicks.com/demo/files/editor/file/75927759138.pdfIn PDF document text
    • http://nepalbestcargo.com/userfiles/file/93313066729.pdfIn PDF document text
    • http://swaving-stalinrichting.nl/ckfinder/userfiles/files/57962433568.pdfIn PDF document text
    • http://www.stadion-zarya.ru/ckfinder/userfiles/files/42207239272.pdfIn PDF document text
    • http://ipea.kr/userData/board/file/gefolomabave.pdfIn PDF document text
    • http://orenprom.com/img/account/file/xirilokonulenajuzobabani.pdfIn PDF document text
    • http://shanghaiqingchen.com/upload/files/9313069249.pdfIn PDF document text
    • http://nirmalapublicschoolerumely.com/userfiles/file/71227995346.pdfIn PDF document text
    • http://noithatnhapkhaugiasi.com/luutru/files/7029867925.pdfIn PDF document text
    • http://kaithompson.com/userfiles/file/nezuzovepagewumegawujo.pdfIn PDF document text
    • http://wildzipper.com/clients/wildzipper/userfiles/file/28435952907.pdfIn PDF document text
    • https://valleyrentals.com/userfiles/file/ratodiwisuxabunufovomaza.pdfIn PDF document text
    • http://relaxzenter.com/uploads/files/jebejevizasimemabeguzup.pdfIn PDF document text
    • http://kwik-it.ru/wp-content/plugins/formcraft/file-upload/server/content/files/1613264b087cf6---funekowobuwowevusopuw.pdfIn PDF document text
    • http://kezmosas.hu/files/file/valafumufekugefewe.pdfIn PDF document text
    • http://rigassprotes.lv/uploadz/file/bofipizarinunojijap.pdfIn PDF document text
    • http://mtreurope.com/ckfinder/userfiles/files/tapurafogiwodiriwota.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_off0000df61.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xDF61 18052 bytes
SHA-256: db02077b59ec6e4a2f8106c5a18bbfd959c47c9003495c2d5fdc48e771fb2284
font_01_sfnt_off00010e65.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x10E65 10964 bytes
SHA-256: b1615c35c7b35a790365a808f9734efb8b2c1c5fb41557b0865b49b8113d2651
font_02_sfnt_off000127b4.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x127B4 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1