Malicious PDF — malware analysis report

Static analysis result for SHA-256 b624e53cc295d979…

MALICIOUS

PDF

85.9 KB Created: 2021-06-12 09:19:43 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 4.8.7) First seen: 2021-10-11
MD5: ce0d6aa136b1dc545bacf1582e226d74 SHA-1: 0e04d864a61f82d382250b364853ef4180b77f54 SHA-256: b624e53cc295d979d45ba5444b83227d7d4a043a29a759cadc751d14ee207ef1
96 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment

The PDF file contains numerous links to external websites, many of which are hosted on compromised WordPress sites using the formcraft plugin. The document body, though heavily obfuscated, contains text related to "Premiere pro wedding project free download", suggesting a lure for users to download files. The ML classifier strongly indicates maliciousness, and the presence of multiple compromised upload links points to a distribution mechanism for malware.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9997

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=premiere+pro+wedding+project+free+download PDF link annotation
    • https://www.tessilgiada.it/wp-content/plugins/formcraft/file-upload/server/content/files/160a547e60adbb---mafozexavisijumudaz.pdfIn PDF document text
    • http://hongshengfish.com/uploadfiles/20210522/210522171425564563xvxva33dz6gc.pdfIn PDF document text
    • https://frennphotography.com/wp-content/plugins/formcraft/file-upload/server/content/files/160b7515de4f0c---kuwevevorigijudijub.pdfIn PDF document text
    • http://www.infranetltd.com/wp-content/plugins/formcraft/file-upload/server/content/files/16082de076b1aa---tinatup.pdfIn PDF document text
    • http://28777886.com/Lpf/UPFILE/userfiles/files/fiverenazemubiwaz.pdfIn PDF document text
    • http://aryajob.com/user_upload/file/44125277252.pdfIn PDF document text
    • http://contentworks.co.za/wp-content/plugins/formcraft/file-upload/server/content/files/1606ef5a4b5e5d---gipozedabeloga.pdfIn PDF document text
    • https://yournew.site/wp-content/plugins/super-forms/uploads/php/files/2m67mgpndql9e5qdu4uge2bhvc/tuvebugamevewujuxesupim.pdfIn PDF document text
    • https://www.marbelitesa.co.za/wp-content/plugins/formcraft/file-upload/server/content/files/1609f9f4ce3689---11706343704.pdfIn PDF document text
    • https://www.sharpeningfactory.com/wp-content/plugins/formcraft/file-upload/server/content/files/160a3b94c45bcf---lipekikufisarunubojot.pdfIn PDF document text
    • https://iescolumbus.org/wp-content/plugins/super-forms/uploads/php/files/e64f85f2858de4c5579298f35e6a681c/1745862775.pdfIn PDF document text
    • http://sam-global.ch/files/file/zenudunefodagu.pdfIn PDF document text
    • https://archcosmeticstudio.com.au/wp-content/plugins/super-forms/uploads/php/files/9cee46c58642d0490e6a970dc9bf433e/38951005449.pdfIn PDF document text
    • https://vico-domrep.com/ckfinder/userfiles/files/voridew.pdfIn PDF document text
    • http://www.adatechotomasyon.net/wp-content/plugins/formcraft/file-upload/server/content/files/160a0522b526f3---setifurabuwojanijowi.pdfIn PDF document text
    • http://edu-family72.ru/content/images/uploads/file/35218863903.pdfIn PDF document text
    • http://www.ascendercorp.com/In PDF document text
    • http://www.ascendercorp.com/typedesigners.htmlIn 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://scripts.sil.org/OFLIn PDF document text

Extracted artifacts 3

Files carved from inside the sample during analysis.

FilenameKindSourceSize
font_00_sfnt_off0001049d.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x1049D 5464 bytes
SHA-256: 8499eeddbf7a848323aba342ac2cdfb988615445d47e976de81de762502d1b9c
font_01_sfnt_off00011738.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x11738 2080 bytes
SHA-256: 1eb139b915f9b3f3ee86d69487263330c778f5c3ae70b6def4cd14c6360aec07
font_02_sfnt_off00012037.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x12037 13084 bytes
SHA-256: 4284ee0489107bb09286c50d28d03a3c385ae35377ed6d1cc094bbdf9d05f248