Malicious PDF — malware analysis report

Static analysis result for SHA-256 d17c24d624a476c0…

MALICIOUS

PDF

102.0 KB Created: 2021-07-25 14:45:10 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-10-14
MD5: 3b9d8e96842cdb65886d57e092bf687e SHA-1: 6680a6b9735bed46c36ba233692f1a1465a96e58 SHA-256: d17c24d624a476c0a16285b0bf144319bf6c9f9625685ace9103d7136e961956
96 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment T1204.002 Malicious Link

The PDF contains numerous links, many pointing to compromised CMS upload directories, indicating a link farm or distribution mechanism. The ML classifier strongly flagged this PDF as malicious. While no scripts were extracted, the presence of multiple links to potentially malicious PDFs hosted on compromised sites suggests a coordinated effort to distribute malware or manipulate search engine results.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9979

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://stroynerud-sm.ru/wp-content/plugins/formcraft/file-upload/server/content/files/160820abaa3559---pivov.pdf In PDF document text
    • http://emons-verlag.net/testarea/cwsCMSlight/media/files/wewalolokuvokafokizigomef.pdfIn PDF document text
    • http://unityproductions.com/upload/files/fefaxireduwirokupelurilo.pdfIn PDF document text
    • http://www.magicapro.it/wp-content/plugins/formcraft/file-upload/server/content/files/160c2e3f4a4b3d---fijiwojukejun.pdfIn PDF document text
    • https://kis-u.com/page_data/file/20210625005432.pdfIn PDF document text
    • https://www.adcgrain.com/wp-content/plugins/super-forms/uploads/php/files/4f9094384d7af933578e78c1a2848259/bapapigugapebepopivowu.pdfIn PDF document text
    • https://sunnyvale.com/wysiwygfiles/file/fukobakaxiginig.pdfIn PDF document text
    • https://bandai-k.com/userfiles/file/tamiwokukerufedef.pdfIn PDF document text
    • https://frennphotography.com/wp-content/plugins/formcraft/file-upload/server/content/files/16081c5331c73c---doraz.pdfIn PDF document text
    • https://frennphotography.com/wp-content/plugins/formcraft/file-upload/server/content/files/160af8b998d6f1---53254895875.pdfIn PDF document text
    • http://photo-preiss.com/upload_files/files/zitizuruvoxa.pdfIn PDF document text
    • http://solarwindependence.com/ckfinder/userfiles/files/84021842062.pdfIn PDF document text
    • https://otdelkamos.ru/wp-content/plugins/super-forms/uploads/php/files/05494e3b6cc584ab0b233caf46976cb8/46766077408.pdfIn PDF document text
    • https://thepetrichortouch.com/wp-content/plugins/super-forms/uploads/php/files/1fhqabflo0qrcb0ignrpohdttv/zajexorigekefodetapuzukap.pdfIn PDF document text
    • http://alwaysfavorentertainment.com/clients/879371/File/jufizojijawizaboganu.pdfIn PDF document text
    • http://polkovnik.su/upload/file/56884872748.pdfIn PDF document text
    • http://konditsionery-reutov.ru/upload_picture/file/mewabinaparazejopozilazos.pdfIn PDF document text
    • https://www.sidertest.it/wp-content/plugins/formcraft/file-upload/server/content/files/160a98576bcfb5---23197474047.pdfIn PDF document text
    • http://www.putnamtaxi.net/wp-content/plugins/formcraft/file-upload/server/content/files/160797559bdb82---56997383322.pdfIn PDF document text
    • http://king-pro.com/userfiles/files/10590582440.pdfIn PDF document text
    • http://www.niziointerior.pl/upload/file/pulexopovojuwowug.pdfIn PDF document text
    • https://incoyun.com/calisma2/files/uploads/10508751680.pdfIn PDF document text
    • https://postele-z-masivu.sk/ckfinder/userfiles/files/vulus.pdfIn PDF document text
    • http://donaldbermanmaimonidesgolf2020.com/clients/0/0d/0d43fbb8ff91cab41fa1b056c0d912a9/File/41448054058.pdfIn PDF document text
    • https://gift-edu.ru/wp-content/plugins/super-forms/uploads/php/files/8b4e2d12983c38844a1e643395b679d5/zafenirijomepa.pdfIn PDF document text
    • https://feedproxy.google.com/~r/1eyvgo/aqOO/~3/YTWXjIUwRh0/uplcv?utm_term=vidas+secas+graciliano+ramos+pdf+completoPDF 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_off00012799.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x12799 18996 bytes
SHA-256: e976e47dd90f86144e538080c3574e01036cc63d6b5ec31d34a4d29ba16ba1c9
font_01_sfnt_off00015607.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x15607 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
font_02_sfnt_off00016e1e.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x16E1E 10932 bytes
SHA-256: 55f7e55d526a7a3926c8338d635a8b08df0b4cc7ed343a29dab60980d6793608