Malicious PDF — malware analysis report

Static analysis result for SHA-256 83ef75cb6d5f4d61…

MALICIOUS

PDF

85.1 KB Created: 2021-08-17 23:53:32 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-09-24
MD5: 4c7cb369c51ce97d61651ab47b2c7ab6 SHA-1: 3a921650d2c3246f00b9a367642143503b39671c SHA-256: 83ef75cb6d5f4d61a6b2ad9b035bfd415b990870a7eb398e1c850a1192d3ff06
156 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment

This PDF document was flagged as malicious by ClamAV and 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 0.9990

Heuristics 6

  • ClamAV: Pdf.Phishing.Trojan-d2568dad23a94d95-d2568dad23a94d95-10044375-0 critical CLAMAV_DETECTION
    ClamAV detected this file as malware: Pdf.Phishing.Trojan-d2568dad23a94d95-d2568dad23a94d95-10044375-0
  • 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.18fire.com/wp-content/plugins/super-forms/uploads/php/files/137139d29e82581d34f866a91e9cd087/netudopevepikijupi.pdf In PDF document text
    • http://www.veronicaneal.com/wp-content/plugins/formcraft/file-upload/server/content/files/1/160776bc56e872---72055725642.pdfIn PDF document text
    • https://www.tai.gr/wp-content/plugins/formcraft/file-upload/server/content/files/160a7041f996eb---lixotiruteleku.pdfIn PDF document text
    • http://goldmustang.com/files/files/29897588036.pdfIn PDF document text
    • https://www.willmarshelter.com/ckfinder/userfiles/files/62536190555.pdfIn PDF document text
    • https://miamivanservice.net/wp-content/plugins/formcraft/file-upload/server/content/files/160a6c7840630e---metevofonujekotemorunilon.pdfIn PDF document text
    • http://helloshoppingnepal.com/userfiles/file/57372434560.pdfIn PDF document text
    • http://harc-ias.vn/Images_upload/files/11660579218.pdfIn PDF document text
    • http://xperion.hu/wp-content/plugins/super-forms/uploads/php/files/e8bef1d9916077b62b41a7e955a0f067/46070574303.pdfIn PDF document text
    • https://nsck-cykelmotion.dk/ckfinder/userfiles/files/22381951779.pdfIn PDF document text
    • https://schmitz.cz/res/file/webuk.pdfIn PDF document text
    • https://rlvanstory.com/wp-content/plugins/super-forms/uploads/php/files/044b1b0b970da809c0cc012539b95ab8/buzijavagetukemutibezire.pdfIn PDF document text
    • http://sibaco.ru/ckfinder/userfiles/files/71358544925.pdfIn PDF document text
    • https://aawyx.com/sites/default/imageuser/file/11971981104.pdfIn PDF document text
    • https://noblacklist.pro/web/img/podborky/files/4044294535.pdfIn PDF document text
    • http://pekingtogo.com/uploads/files/23644267666.pdfIn PDF document text
    • http://2girlstrippin.com/wp-content/plugins/formcraft/file-upload/server/content/files/160dc381d8f235---50542861946.pdfIn PDF document text
    • http://www.cascinasorigherio.it/wp-content/plugins/formcraft/file-upload/server/content/files/1608b421166f7e---buxigiroxerojanis.pdfIn PDF document text
    • http://kino-profi.com/wp-content/plugins/super-forms/uploads/php/files/3205f37b9dbf037cdf245f38fe9cbdec/rorinaxewimekuxuwamapar.pdfIn PDF document text
    • http://iglozawiercie.pl/zdjecia/file/90422001776.pdfIn PDF document text
    • http://esen-life.com/userfiles/file/joziditivesubunufalo.pdfIn PDF document text
    • https://jetaime-shop.com/files/banatav.pdfIn PDF document text
    • http://msci.com.ng/wp-content/plugins/formcraft/file-upload/server/content/files/160c9e8dd70e7b---ziwowob.pdfIn PDF document text
    • https://ferado.vn/userfiles/file/dukojagogelob.pdfIn PDF document text
    • https://feedproxy.google.com/~r/skout/mBVl/~3/PmAiG5ZyT-k/uplcv?utm_term=exercices+sym%C3%A9trie+centrale+4eme+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_off0000e3a5.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xE3A5 18460 bytes
SHA-256: ab261d3db21fe76fcb611a489d20eafd4cda0fd79690d495418f84bfef83e148
font_01_sfnt_off0001123a.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x1123A 11092 bytes
SHA-256: 78f2a25cee3e545b4c58d1f674c2ff758e6b46e6240062d3f20cf498732b1268
font_02_sfnt_off00012bda.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x12BDA 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1