Malicious PDF — malware analysis report

Static analysis result for SHA-256 b39094d32a78052c…

MALICIOUS

PDF

73.8 KB Created: 2021-09-08 07:19:13 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-10-27
MD5: e615e4b02e4ecbf79a10c5f455eec990 SHA-1: daa0c2905a2df23b63e05c4668dd12e9ce8501ca SHA-256: b39094d32a78052c5f3749fa80a54f7b50b1e71694af7297259a02ed889171b4
96 Risk Score

Malware Insights

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

The PDF contains a large number of external links, many pointing to PDFs hosted on domains that appear to be compromised WordPress sites. The ML classifier also flagged this PDF as malicious with high confidence. The presence of a link farm suggests an attempt to manipulate search engine results or to distribute further malicious content.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9976

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://robedecreateur.com/img/files/97266218656.pdf In PDF document text
    • http://galenbio.com/images/upload/file/62242875078.pdfIn PDF document text
    • https://huanghecables.com/d/files/46306418150.pdfIn PDF document text
    • https://www.emmabowman.com/wp-content/plugins/super-forms/uploads/php/files/902da004aa174fa6bf4754f448826cdc/22765221115.pdfIn PDF document text
    • http://stkvn.ru/wp-content/plugins/super-forms/uploads/php/files/1e4bd7130f5887756bb9dcfd29eabaff/82787588296.pdfIn PDF document text
    • http://project-lovcen.me/userfiles/file/22077902204.pdfIn PDF document text
    • http://shinserviceodi.ru/wp-content/plugins/super-forms/uploads/php/files/09ddfbb0ed49abc8c2d330ffb17f0e6b/36229643638.pdfIn PDF document text
    • https://www.andimoda.com/wp-content/plugins/super-forms/uploads/php/files/69c8d5c43b16eef7492d168ab26ca0a0/tajopino.pdfIn PDF document text
    • http://birzebbugastpetersfc.com/files/file/56127233209.pdfIn PDF document text
    • https://hunghiephuylog.com/upload/files/gofojar.pdfIn PDF document text
    • http://fantasypartyentertainment.com/wp-content/plugins/formcraft/file-upload/server/content/files/160b2f0f0777e3---bejifafazutewebiv.pdfIn PDF document text
    • https://t2sc.me/userfiles/dawizomitelunorigosupo.pdfIn PDF document text
    • https://www.chesapeake-lighting.com/wp-content/plugins/super-forms/uploads/php/files/a33a8809933e3c4e4dba9ac22baaa174/wetusapugom.pdfIn PDF document text
    • https://michaels-limo.com/wp-content/plugins/formcraft/file-upload/server/content/files/161358fa89312a---56470553044.pdfIn PDF document text
    • https://www.indee-r.fr/wp-content/plugins/super-forms/uploads/php/files/2a417281ca1e0e562c4a9eda1ea440bd/24926306386.pdfIn PDF document text
    • http://vatlieulamnha.com/media/ftp/file/70616846702.pdfIn PDF document text
    • http://europeanprofservices.com/wp-content/plugins/formcraft/file-upload/server/content/files/16077a39849e02---fevawuzefulez.pdfIn PDF document text
    • https://granitnet.hu/editor_up/sonudaxilowubusalinevupu.pdfIn PDF document text
    • https://imapcb.org/wp-content/plugins/super-forms/uploads/php/files/hdikitsguu9rr4tcdt2hcsp6s4/wisajitapimaxutoxuwu.pdfIn PDF document text
    • http://bright-mineral.com/uploadfile/file/2021071611302877.pdfIn PDF document text
    • http://bona-agra.pl/Upload/file/40063714934.pdfIn PDF document text
    • http://toonesk.com/upload/24890154669.pdfIn PDF document text
    • https://couvreur-hautdoubs.fr/internet_new/images_et_fichiers//file/55116782106.pdfIn PDF document text
    • https://feedproxy.google.com/~r/Uplcv/~3/LPIa9PGmDLg/uplcv?utm_term=resignation+letter+model+pdfPDF 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_off0000bd99.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xBD99 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
font_01_sfnt_off0000d5b0.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xD5B0 10884 bytes
SHA-256: e035603522e13159f200d522f095c577f421d02e7ee84700cf18c1b4a85605cf
font_02_sfnt_off0000ee9f.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xEE9F 16656 bytes
SHA-256: 720b0efd3b6664479689001e779448c72eff56c7a86f864a32b9f53dd93ec444