Malicious PDF — malware analysis report

Static analysis result for SHA-256 b723e43464a7d4a5…

MALICIOUS

PDF

90.0 KB Created: 2021-08-07 13:48:39 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-09-14
MD5: 3d25c4f1ac047d10975767d8bd9294d0 SHA-1: f0ae837d0ca5ebaa09e1b498b00b86f0056d91ad SHA-256: b723e43464a7d4a5bb4b5a73e2936439e53e6218facc40971b5aafe846ad067f
156 Risk Score

Malware Insights

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

The file was detected as malicious by ClamAV and an ML classifier, indicating a high likelihood of malicious intent. It functions as a link farm, with numerous embedded URLs pointing to various domains, many of which appear to be compromised or disposable hosting. This pattern is commonly used to distribute phishing content or redirect users to malware download sites.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9876

Heuristics 6

  • ClamAV: Pdf.Phishing.Trojan-d2528dad23a95d95-d2528dad23a95d95-10044376-0 critical CLAMAV_DETECTION
    ClamAV detected this file as malware: Pdf.Phishing.Trojan-d2528dad23a95d95-d2528dad23a95d95-10044376-0
  • 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 http://triatlonbizuterie.cz/sites/default/files/file/sobatetoparuwajutagel.pdf In PDF document text
    • http://waypl.pl/upload/File/ruregiritowojagitabi.pdfIn PDF document text
    • https://craft-personal.de/userfiles/file/43060286905.pdfIn PDF document text
    • http://xperion.hu/wp-content/plugins/super-forms/uploads/php/files/6eae631b0b4df6ca51eb20930b4d2bfa/42323040138.pdfIn PDF document text
    • http://abapaposentados.com.br/wp-content/plugins/formcraft/file-upload/server/content/files/16085b0ee8907a---mopinepadalubegijod.pdfIn PDF document text
    • http://www.advancedevents.ro/wp-content/plugins/formcraft/file-upload/server/content/files/16079ca71307aa---51781428315.pdfIn PDF document text
    • http://architects-desk.com/uploadsfile/medefivozetokelim.pdfIn PDF document text
    • http://bracyfamilyreunion.com/clients/c/c2/c2db1a97f769835965582c74015c7782/File/36548293287.pdfIn PDF document text
    • http://kfnmdg.com/upfolder/e/files/20210612132015.pdfIn PDF document text
    • http://www.farparts.cl/wp-content/plugins/formcraft/file-upload/server/content/files/160ae31d70204d---84923603336.pdfIn PDF document text
    • http://discoveryenglish.org/wp-content/plugins/formcraft/file-upload/server/content/files/160e5d27201fef---50814129131.pdfIn PDF document text
    • http://s-box.biz/upload/datoteke/72442301846.pdfIn PDF document text
    • http://www.onegelha.com/wp-content/plugins/super-forms/uploads/php/files/a798b638f3ad3f58d0dbf92cf07d1c67/74510328128.pdfIn PDF document text
    • http://makesrealsense.com/ckfinder/userfiles/files/zonobigiwabij.pdfIn PDF document text
    • http://xn--zb0bw3kv4s8mn.com/upload/fckeditor/file/favibozenefinijowomeli.pdfIn PDF document text
    • http://anhuishangbiao.com/upload_fck/file/2021-6-17/20210617011142167397.pdfIn PDF document text
    • http://www.optionassurance.ca/wp-content/plugins/formcraft/file-upload/server/content/files/16073c87a99872---97808127999.pdfIn PDF document text
    • http://assessmentinsight.com/ckfinder/userfiles/files/laman.pdfIn PDF document text
    • https://www.certificagreen.com/wp-content/plugins/formcraft/file-upload/server/content/files/160749605e4b7b---bomulin.pdfIn PDF document text
    • http://www.rkcomdesignservices.com/wp-content/plugins/formcraft/file-upload/server/content/files/16072b3a10ebe2---54894500535.pdfIn PDF document text
    • http://drshapard.com/clients/73598/File/moxonupajopukabinuxebo.pdfIn PDF document text
    • https://husvagnsexpo.se/wp-content/plugins/formcraft/file-upload/server/content/files/16081cd9c5968f---zakuv.pdfIn PDF document text
    • http://olimpic.hu/ckfinder/userfiles/files/rasetakojubifugi.pdfIn PDF document text
    • https://wlao.on.ca/wp-content/plugins/super-forms/uploads/php/files/1c3e20159e06209affd6b3716ee7c8ee/35404126020.pdfIn PDF document text
    • https://stakeoutllc.com/wp-content/plugins/super-forms/uploads/php/files/c043bc107cb2ea5684406a4e720bb1c0/67641535082.pdfIn PDF document text
    • https://daluxerealty.com/wp-content/plugins/super-forms/uploads/php/files/3n0b0d478r3c5qeg3tqliqn3u2/sowodunor.pdfIn PDF document text
    • https://feedproxy.google.com/~r/skout/mBVl/~3/3CAf4wW3hvY/uplcv?utm_term=7+chakra+guided+sleep+meditationPDF 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_off0000fa8b.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xFA8B 11108 bytes
SHA-256: c7f846eca197049e37de2e0e091e59dfe7452cb69e46defd2e2ca35fd5085f3a
font_01_sfnt_off0001141b.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x1141B 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
font_02_sfnt_off00012c2d.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x12C2D 16764 bytes
SHA-256: 1bb1a4ab848aeacb77b4e4ebbd863d63551aae8a21687b23b55e54efcd125e2c