Malicious PDF — malware analysis report

Static analysis result for SHA-256 55a138884d07f74c…

MALICIOUS

PDF

81.3 KB Created: 2021-06-13 12:52:57 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 4.8.7) First seen: 2021-09-27
MD5: 3804d2cb139560558e186528db67854b SHA-1: 87f92b2517424e47e73b0ad94d81a527d42c85f4 SHA-256: 55a138884d07f74c0c56f8c9cc6f06e29f20af08bf57b673be8eca59e002c78a
156 Risk Score

Malware Insights

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

The PDF document contains numerous external URIs and is identified as a link farm, with many links pointing to compromised CMS uploads. The ML classifier and ClamAV detection strongly indicate malicious intent, likely for phishing or malware distribution. The document body's garbled content suggests it's not intended for direct user reading but rather to host these malicious links.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9998

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://philabc.ru/uplcv?utm_term=minecraft+mobile+shaders PDF link annotation
    • http://apexhealthnutrition.com/newerac2c/userfiles/file/nulofamukapotos.pdfIn PDF document text
    • http://www.anieliasfx.com/uploads/textareas/file/98696393854.pdfIn PDF document text
    • http://heilpraxis-pankow.de/wp-content/plugins/formcraft/file-upload/server/content/files/16086e0c7d192f---20973618056.pdfIn PDF document text
    • http://trenermichal.pl/wp-content/plugins/formcraft/file-upload/server/content/files/160b04ccd4b162---69180669240.pdfIn PDF document text
    • https://cullinanconstruction.com/wp-content/plugins/super-forms/uploads/php/files/t08m6g8cf8pfjjjj60ord83gm3/52928548460.pdfIn PDF document text
    • https://amagi.la/wp-content/plugins/formcraft/file-upload/server/content/files/160bab229be954---rozetarobasuzolututenafaw.pdfIn PDF document text
    • http://hillcountryawningsandsunscreens.com/wp-content/plugins/formcraft/file-upload/server/content/files/1607629dba813c---15633411085.pdfIn PDF document text
    • http://desagresbrts.com/clients/34568/File/26061754877.pdfIn PDF document text
    • https://balance-global.com/wp-content/plugins/super-forms/uploads/php/files/bv1ukklono1pndtr2bdjlqct4t/pogibezawoxefe.pdfIn PDF document text
    • https://agrachoff.ru/wp-content/plugins/super-forms/uploads/php/files/25fbe523c9a2d9221345cb76d0cf7f68/sarifibulizilebawawi.pdfIn PDF document text
    • http://mid-europe-ex.com/bavub.pdfIn PDF document text
    • https://maugli24.ru/wp-content/plugins/super-forms/uploads/php/files/3ae4154f046877dfb95cf7b32bb812b6/wonofufejivas.pdfIn PDF document text
    • http://xn--80ackbssfuieecff0e8c.xn--p1ai/wp-content/plugins/super-forms/uploads/php/files/gt121nj1nmskgn9t16r0rmgar5/93156885255.pdfIn PDF document text
    • http://anhuizpyy.com/upload_fck/file/2021-5-16/20210516155734598442.pdfIn PDF document text
    • https://mimpishio1.com/contents//files/tewilugusepibapiriv.pdfIn PDF document text
    • http://www.rolstoellift.com/wp-content/plugins/formcraft/file-upload/server/content/files/1606f4cc0653ae---madaxitavalegipeg.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
    • 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_off0000e803.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xE803 5408 bytes
SHA-256: dbb1eddfe74960d48e5188404ba99fb95ffca00c8f706cf64d73f90c8f33a05c
font_01_sfnt_off0000fa43.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xFA43 12280 bytes
SHA-256: df3a01626de4b33c25655bc945cc16ca70e8b462f94094ffa66e6e54ad0a6f18
font_02_sfnt_off000122ca.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x122CA 16204 bytes
SHA-256: 541fa2b6826b0add99b7d5a173ef1e6a5567607b5192f75b810eb17d6a563501