Malicious PDF — malware analysis report

Static analysis result for SHA-256 1ca71d0907faa637…

MALICIOUS

PDF

81.1 KB Created: 2021-09-08 01:56:53 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-10-05
MD5: ec57fecd8455e69fbc829dd0f51d2149 SHA-1: eee1dd8fb3b85f013207680dd1cb00e043b4aa0e SHA-256: 1ca71d0907faa6375deb8ec01f5470f55e0a9737a78f826924a53711c4f98105
164 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment

The PDF contains embedded JavaScript, a common technique for executing malicious code. It also features a link farm pointing to multiple distinct hosts, many of which appear to be compromised WordPress sites, suggesting an attempt to obscure the final malicious destination. The ClamAV detection and ML classifier strongly indicate malicious intent, likely for phishing or malware delivery.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9949

Heuristics 7

  • 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.
  • Embedded JS stream low PDF_JS
    PDF references a /JS stream. Generic JavaScript is common in benign forms; specific dangerous APIs are scored by separate rules.
  • 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://cbolean.com/wp-content/plugins/super-forms/uploads/php/files/2522388ec4ca22ddfe043b9785b098b8/90088288196.pdf In PDF document text
    • https://t2sc.me/userfiles/bulipigadonuguvozupizuj.pdfIn PDF document text
    • https://www.marthatrotts.ca/wp-content/plugins/formcraft/file-upload/server/content/files/1606c95c548bed---9483492769.pdfIn PDF document text
    • http://www.fsnn.se/wp-content/plugins/formcraft/file-upload/server/content/files/1607d6b6883f2c---buvotozuwizorife.pdfIn PDF document text
    • https://www.helpfulhunks.com.au/wp-content/plugins/formcraft/file-upload/server/content/files/160c8d523372f5---30828517607.pdfIn PDF document text
    • http://kindervakantieweekdeurne.nl/wp-content/plugins/formcraft/file-upload/server/content/files/1607502de13460---85542233502.pdfIn PDF document text
    • http://aardbeienfeesten.nl/uploadimages/files/tupazumozeniradat.pdfIn PDF document text
    • http://barrarioservicos.com.br/wp-content/plugins/formcraft/file-upload/server/content/files/160865135535a2---dapedupugurifebed.pdfIn PDF document text
    • http://tanabuauto.com/js/upload/files/58670816744.pdfIn PDF document text
    • https://costumeworld.com/wp-content/plugins/formcraft/file-upload/server/content/files/1606f68ccbfc53---tatibumaxipez.pdfIn PDF document text
    • http://nnhs1964.com/clients/a/a2/a2d7b74ded15306de89ee4bbe2f7ed3f/File/penuxavuzev.pdfIn PDF document text
    • http://wbbray.com/wp-content/plugins/formcraft/file-upload/server/content/files/1606c883c459f1---45878939996.pdfIn PDF document text
    • http://solee.cn/ckfinder/userfiles/files/mawuzisubuvuxesarusipup.pdfIn PDF document text
    • http://www.investing-in-women.com/wp-content/plugins/formcraft/file-upload/server/content/files/160840806caad9---94783748875.pdfIn PDF document text
    • http://steclotildehorton.ca/wp-content/plugins/formcraft/file-upload/server/content/files/16087cc31964ab---rizepujobewefaredevusate.pdfIn PDF document text
    • http://www.acefence.com/wp-content/plugins/formcraft/file-upload/server/content/files/160c72b3e23708---12733374530.pdfIn PDF document text
    • https://thietbivesinhanhhuy.com/asset/files/vixarufuxilapep.pdfIn PDF document text
    • https://stpetejazz.com/wp-content/plugins/super-forms/uploads/php/files/9ldhibu0hlplm8r6ci1sgnf54a/42919022598.pdfIn PDF document text
    • http://rudolphalexander.com/uploads/files/89110305813.pdfIn PDF document text
    • http://willtorock.com/wp-content/plugins/formcraft/file-upload/server/content/files/1606c90eabab52---kanitinixipexubeb.pdfIn PDF document text
    • http://djpress.pl/Image/files/67635751764.pdfIn PDF document text
    • http://secretinvitation.net/images/files/30599474486.pdfIn PDF document text
    • http://tsrmmessina.it/userfiles/files/530282521.pdfIn PDF document text
    • https://rmdschoolandcollege.com/wp-content/plugins/super-forms/uploads/php/files/dd32eb8eea45586757cd62a228819856/58460983211.pdfIn PDF document text
    • http://www.iycadana.org/wp-content/plugins/super-forms/uploads/php/files/p06cnu7q7ecughpd82bj7110v4/kuxodebiduvova.pdfIn PDF document text
    • https://feedproxy.google.com/~r/Uplcv/~3/3CAf4wW3hvY/uplcv?utm_term=pink+panther+piano+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_off0000d800.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xD800 18208 bytes
SHA-256: fd3190b726ffb5e650eb8eb47e81e9ebbda44d5e282a3a521601b9b1d1defc6b
font_01_sfnt_off00010835.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x10835 10472 bytes
SHA-256: 9fef8c90dcc7ddbe8646391e77382b6431fd31a67a236b6ac60bec456dfd04f7
font_02_sfnt_off00011fe9.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x11FE9 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1