Malicious PDF — malware analysis report

Static analysis result for SHA-256 f92b26ee7cb77085…

MALICIOUS

PDF

85.0 KB Created: 2021-06-30 12:24:26 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3)
MD5: 5f5bb7b8a16514671c9fe60504689037 SHA-1: 5b282c8ded0e306e0126c8c4163c29ff65028075 SHA-256: f92b26ee7cb7708554648319307a558b1e9ee9a1530c9ee4f5c892eeccc9c746
156 Risk Score

Malware Insights

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

The PDF was flagged by ML classifiers and ClamAV as malicious, specifically as a phishing trojan. It contains a link farm pointing to numerous URLs, many hosted on compromised WordPress sites, suggesting an attempt to lure users to malicious content. The document body is heavily obfuscated and appears to be generated by wkhtmltopdf, indicating it's not intended for direct user reading but rather as a container for these links.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9964

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://tangiahoang.com/skinkorea/Images_upload/files/pawumodesuzumadumisare.pdf
    • https://amrapalispot.com/userfiles/file/71070713071.pdf
    • https://aihr-iadh.org/uploads/FCK_files/file/fuweti.pdf
    • http://paynechapelduquesne.org/clients/9/9b/9b910c66cef3ae2d1bb1fd5804160a19/File/lisoxuxagatiwuzuvilomebe.pdf
    • https://anzmrrn.org/wp-content/plugins/formcraft/file-upload/server/content/files/1607d4f4065da0---61429053525.pdf
    • https://www.okcfarmersmarket.com/wp-content/plugins/super-forms/uploads/php/files/4f1047f3c5624e0e08c08fcf5b35c60b/vunijazivafow.pdf
    • https://eduinfinite.com/wp-content/plugins/super-forms/uploads/php/files/7bb9ef6be7516fad92524fc3cbbc4711/zininojulavekabofi.pdf
    • https://www.reflectionuk.com/wp-content/plugins/super-forms/uploads/php/files/cn2b66mqo2qt2tsto70bbjk98k/24694051190.pdf
    • https://soltendance.com/stockages/files/94405801809.pdf
    • http://www.rebranded.tv/wp-content/plugins/formcraft/file-upload/server/content/files/160a87dad13f05---45096162375.pdf
    • http://www.sunarsurdurulebilir.com/wp-content/plugins/super-forms/uploads/php/files/90tb5l985vjicd5udo79jr5lc3/43098142037.pdf
    • https://alarrabnews.com/images/content/content/file/80418748881.pdf
    • http://constructionone.com.br/wp-content/plugins/formcraft/file-upload/server/content/files/160b35d0ade06a---mubafoz.pdf
    • http://albino-pitti.com/pub_img/file/bujomojewe.pdf
    • https://carpanea.it/wp-content/plugins/super-forms/uploads/php/files/8a8a2a2fbe9e704787077c9486980b6a/towakamidazepazikodukifo.pdf
    • http://phaptangpgvn.net/app/webroot/upload/files/latolo.pdf
    • http://hephatha100.com/clients/4/45/452f9a9cd3514f90eb92b3b4734a1f1d/File/lujajezuditebusa.pdf
    • https://shriayurvednagpur.org/public/ckfinder/userfiles/files/kerativilaj.pdf
    • http://augsburger-dartliga.de/uploads/file/38048702763.pdf
    • http://lowndes85.com/clients/d/d3/d39312ffd46aa2fbcc4e4de04d96a17f/File/91421370444.pdf
    • https://www.psalighting.com/wp-content/plugins/super-forms/uploads/php/files/29af06bdcdc37ad67cecb55179766792/39827148972.pdf
    • https://emmaushuis.org/pages/wanotugetonuduzes.pdf
    • https://feedproxy.google.com/~r/skout/mBVl/~3/3vuEKuznOb8/uplcv?utm_term=definition+of+perfect+continuous+tense
    • http://www.w3.org/1999/02/22-rdf-syntax-ns#
    • http://purl.org/dc/elements/1.1/
    • http://ns.adobe.com/pdf/1.3/
    • http://ns.adobe.com/xap/1.0/
    • http://ns.adobe.com/xap/1.0/mm/
    • http://ns.adobe.com/xap/1.0/rights/
    • http://dejavu.sourceforge.net
    • http://dejavu.sourceforge.net/wiki/index.php/License

Extracted artifacts 3

Files carved from inside the sample during analysis.

FilenameKindSourceSize
font_00_sfnt_off0000e910.bin
a634eb9b1a7bed3cfa4053a819f11bb81914d4f80eeb26cef1eadb73d954e3ff
pdf-font-stream PDF embedded font (sfnt) at offset 0xE910 10368 bytes
font_01_sfnt_off000100a9.bin
9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
pdf-font-stream PDF embedded font (sfnt) at offset 0x100A9 16792 bytes
font_02_sfnt_off000118bb.bin
c4733f002fab45738db760615252ff6d0c6d54abc615460c96fe79059b633d96
pdf-font-stream PDF embedded font (sfnt) at offset 0x118BB 17800 bytes