Malicious PDF — malware analysis report

Static analysis result for SHA-256 a8cdc4d13976a838…

MALICIOUS

PDF

116.5 KB Created: 2021-05-13 08:07:24 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 4.8.7) First seen: 2021-10-24
MD5: d194ee6b2a5db79ed0c77cbdfe6a1f1c SHA-1: 85513903d348ceb11cd14f7ef602d3fee63d100b SHA-256: a8cdc4d13976a838f5e5c941476b0c9dc852fd7a108ec72c4cd86bb4580dce1c
156 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment T1059.007 JavaScript

The file is identified as malicious by ML classifiers and ClamAV, specifically as a phishing trojan. It contains numerous links to compromised WordPress sites, suggesting a link farm designed to redirect users to malicious content. The document body, though heavily obfuscated, appears to be a lure related to 'Ap calculus derivatives practice worksheet', indicating a social engineering attempt. No scripts were extracted, but the presence of multiple external links points to a phishing or malware distribution vector.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9996

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.mnspineandsport.com/wp-content/plugins/super-forms/uploads/php/files/e0802009d7a3d5b0cf8b5996a99d9c63/wufetetusikidoz.pdf In PDF document text
    • https://realestateconnect.biz/wp-content/plugins/super-forms/uploads/php/files/nltcbj934k0bubv5mpdm43hs25/neduxibididusizobane.pdfIn PDF document text
    • http://for-rent-leuven.com/wp-content/plugins/formcraft/file-upload/server/content/files/1606f1038f2150---77053810352.pdfIn PDF document text
    • http://www.davidwoodpersonnel.com/wp-content/plugins/formcraft/file-upload/server/content/files/16084159c0c58d---zelir.pdfIn PDF document text
    • http://lilit-realty.com/wp-content/plugins/super-forms/uploads/php/files/c2pk5qh1u081c707uhlstrcc51/dudazelul.pdfIn PDF document text
    • https://fermuar.com/wp-content/plugins/formcraft/file-upload/server/content/files/16084b62575bcd---79380825017.pdfIn PDF document text
    • http://bclgrouptt.com/userfiles/file/bedipagorexubesaki.pdfIn PDF document text
    • https://kalatranslation.co.uk/wp-content/plugins/super-forms/uploads/php/files/027ta3c12m26s0lqa1dli7fvv3/garujajabibizis.pdfIn PDF document text
    • http://www.platformliften.info/wp-content/plugins/formcraft/file-upload/server/content/files/16073b22dbebff---68097815715.pdfIn PDF document text
    • https://seataclightingalaska.com/wp-content/plugins/super-forms/uploads/php/files/1fa87972b40d327d3d443679866eca55/94986541741.pdfIn PDF document text
    • https://www.tangelo.no/wp-content/plugins/formcraft/file-upload/server/content/files/16075626a96c91---lasanupejanigatinel.pdfIn PDF document text
    • https://advancedcheckcashadvance.com/wp-content/plugins/formcraft/file-upload/server/content/files/160814ad8a6adf---sinurewusow.pdfIn PDF document text
    • http://xn--80ackbssfuieecff0e8c.xn--p1ai/wp-content/plugins/super-forms/uploads/php/files/3a5j1baq9n737035si1je1qlr1/16578251619.pdfIn PDF document text
    • https://www.analfissur.com/wp-content/plugins/formcraft/file-upload/server/content/files/16081cf140507d---97196683502.pdfIn PDF document text
    • https://laihouston.com/wp-content/plugins/super-forms/uploads/php/files/cec3ab411e1fc57326cad58fff8d5f2b/28822295680.pdfIn PDF document text
    • https://ladychief.com/wp-content/plugins/super-forms/uploads/php/files/1bbda37f231381d0af37b44839ddc3e2/dojepukedemuxexutozipexub.pdfIn PDF document text
    • https://chicagoportablexray.com/wp-content/plugins/formcraft/file-upload/server/content/files/1608fe905afc6e---tubatoti.pdfIn PDF document text
    • http://www.ascendercorp.com/In PDF document text
    • http://www.ascendercorp.com/typedesigners.htmlIn PDF document text
    • https://feedproxy.google.com/~r/Uplcv/~3/3vuEKuznOb8/uplcv?utm_term=ap+calculus+derivatives+practice+worksheetPDF 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://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 4

Files carved from inside the sample during analysis.

FilenameKindSourceSize
font_00_sfnt_off00015d5b.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x15D5B 3396 bytes
SHA-256: f3d257f94f7f0d99f568e074b133e4534c10b750647f5143c284501d102ba2b8
font_01_sfnt_off000169a9.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x169A9 5364 bytes
SHA-256: ac343b96d70f2698c1ee45396694e3c0fc165e8c6a7bf43d72ea8d4ac1acdfae
font_02_sfnt_off00017bf5.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x17BF5 15468 bytes
SHA-256: 0895b5afa2b2ac9ef95c4fa3a52cc65341dd1ed74f586b78873dccfbebf37484
font_03_sfnt_off0001aed2.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x1AED2 16136 bytes
SHA-256: 7a480da6098dba5ec41d0e0b259bc1c599d8fad8527bffd51ebc419496f13d0b

Open this report in the interactive analyzer, or submit your own file for analysis.