Malicious PDF — malware analysis report

Static analysis result for SHA-256 c85a8d47c3c62a6d…

MALICIOUS

PDF

72.8 KB Created: 2021-09-08 03:16:22 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-10-07
MD5: 35eecb1499c5a0df6daa95474431a32b SHA-1: 999109fc0080da61690a036dc79a2585119bae03 SHA-256: c85a8d47c3c62a6d2a82a8431d6d2b45578d7216190b1420e17592140d1a7d84
156 Risk Score

Malware Insights

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

This PDF 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 websites, some of which are hosted on compromised WordPress uploads. The primary purpose appears to be directing users to potentially malicious or phishing content, leveraging a common tactic for initial access via spearphishing attachments.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9840

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 http://humboldthighclassof79.com/clients/1/19/19f040aad945c40a0acbd79abd3dc6cb/File/68425526847.pdf In PDF document text
    • https://themodernla.com/wp-content/plugins/super-forms/uploads/php/files/dcbcf18c519bb5ce30834ec1f5f53f45/8670238537.pdfIn PDF document text
    • http://metamorfoza-krosno.pl/userfiles/file/tefawivupaxenapufog.pdfIn PDF document text
    • https://www.allterra.group/wp-content/plugins/super-forms/uploads/php/files/6ca46184f174d718219ae69697d44ed6/35980016279.pdfIn PDF document text
    • http://www.dramayaramendes.com.br/wp-content/plugins/formcraft/file-upload/server/content/files/16070e91639fb9---12514943256.pdfIn PDF document text
    • http://olimpic.hu/ckfinder/userfiles/files/91261558740.pdfIn PDF document text
    • http://emailreceptionist.net/userfiles/file/fosiw.pdfIn PDF document text
    • http://bawaconstructions.com/editorData/file/12242866647.pdfIn PDF document text
    • http://longarmquiltacademy.com/fckeditor/userfiles/file/81098829018.pdfIn PDF document text
    • https://s-h.cc/uploads//files/202107312104355014.pdfIn PDF document text
    • https://activepymes.com/pub/file/7175643292.pdfIn PDF document text
    • http://livilgirls.com/files/lebinibunuzuwoko.pdfIn PDF document text
    • https://cristiandellavedova.com/wp-content/plugins/super-forms/uploads/php/files/9t3t0p9ljroj0envsmdlepq9s3/25071768648.pdfIn PDF document text
    • http://www.saraviation.com/wp-content/plugins/formcraft/file-upload/server/content/files/16120d4a9890e2---68616636459.pdfIn PDF document text
    • http://sarica.com.tr/ckfinder/userfiles/files/kagegamodaruraxabepidok.pdfIn PDF document text
    • http://gradn.ru/uploades/fckeditorfile/60156154694.pdfIn PDF document text
    • https://carthink.org/wp-content/plugins/formcraft/file-upload/server/content/files/1609093d909220---11677149049.pdfIn PDF document text
    • http://jaatkinson.com/userimages/furuji.pdfIn PDF document text
    • http://slenderclub.cz/ckfinder/userfiles/files/49862712815.pdfIn PDF document text
    • https://fieldofgreen.com/wp-content/plugins/super-forms/uploads/php/files/3b500d5d781fc25912b4857e03569ef4/28779154447.pdfIn PDF document text
    • http://a-swiss.com/upload/userfiles/file/42638430519.pdfIn PDF document text
    • https://agilitynd.com/wp-content/plugins/super-forms/uploads/php/files/fbcf28341e935041cb61c2013728feaa/duwoduxeki.pdfIn PDF document text
    • https://globalcareerclub.com/FCKeditor/userfiles/file/69099397130.pdfIn PDF document text
    • https://cissud.com/uploads/ck_editor/files/24552131894.pdfIn PDF document text
    • https://readandenjoy.ae/userfiles/files/kosegepor.pdfIn PDF document text
    • https://stradatextiles.com/upload/ckfinder/files/68280398211.pdfIn PDF document text
    • https://feedproxy.google.com/~r/Uplcv/~3/cv9VXjIrmdE/uplcv?utm_term=prensa+manual+para+hacer+tortillasPDF 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_off0000b9e6.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xB9E6 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
font_01_sfnt_off0000d1f8.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xD1F8 16936 bytes
SHA-256: 6965c526b57b02cf89288bdc055cb1a08361fa7d3388cc047561d2d0946f0f90
font_02_sfnt_off0000fd2a.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xFD2A 10740 bytes
SHA-256: be0a1def1a333443d03b6985b4c096dcddc1dbb7857db548a6f7b58404c64e9b