Malicious PDF — malware analysis report

Static analysis result for SHA-256 fb5c0f2eb6c002f8…

MALICIOUS

PDF

68.5 KB Created: 2021-09-26 14:08:14 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-11-25
MD5: 261758eddb90e2beb9a9d4c5a6edf1ec SHA-1: 90e3213e03f04d2d8e2790fd10d299a3d4d778ff SHA-256: fb5c0f2eb6c002f8748dc1a9c2cf7c78751cd82ca306e209d9803ed5cd0e2dcd
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 numerous URLs pointing to compromised websites and disposable hosting, indicating a link farm designed to redirect users to malicious content. The document body is heavily obfuscated and appears to be generated by wkhtmltopdf, suggesting it's not intended for direct user reading but rather as a container for malicious links.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9982

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://garglob.ru/uplcv?utm_term=pros+and+cons+of+android+tv PDF link annotation
    • http://partner-support.net/user_data/userfiles/files/refogexufudugox.pdfIn PDF document text
    • http://carrozzeriardue.it/userfiles/files/18573240365.pdfIn PDF document text
    • http://diagnosticaedilizia.com/userfiles/files/34797522828.pdfIn PDF document text
    • http://www.myhhsi.com/wp-content/plugins/super-forms/uploads/php/files/43b73266793b5f7170b92dc23d0e4abe/fajubusitiwewigabure.pdfIn PDF document text
    • http://robedecreateur.com/img/files/darizolupuboxopivuj.pdfIn PDF document text
    • http://aadcnfgl.netsociality.com/upload/files/84993996391.pdfIn PDF document text
    • https://truckforceone.eu/upload/editor/file/jipejidaxeni.pdfIn PDF document text
    • https://www.infratechgroep.nl/wp-content/plugins/super-forms/uploads/php/files/5feda52302b020f5c32f69a5dbfe7db4/52381546491.pdfIn PDF document text
    • http://mertcelikkapi.com/userfiles/file/74062628869.pdfIn PDF document text
    • http://gwynnoak.abwingsmd.com/uploads/files/63175822378.pdfIn PDF document text
    • http://secureyun.cn/uploadfile/file///2021092217460066.pdfIn PDF document text
    • https://callmarkinvestments.fortunekenya.com/callmark/files/55970264172.pdfIn PDF document text
    • http://a-xian-coat.com/uploads/files/202109011359595139.pdfIn PDF document text
    • https://manajrgvaaradhi.com/cms-uploads/files/90731082286.pdfIn PDF document text
    • http://tecnoservizi.com/userfiles/files/zifakokelidejizodumi.pdfIn PDF document text
    • https://halkapsikoloji.com/userfiles/file/ninotemego.pdfIn PDF document text
    • http://bolt-go77.com/fckeditor/userfiles/file/moforadipatowiradudop.pdfIn PDF document text
    • https://rmp-traueranzeigen.de/cms/files/nagekizikezasezufuwa.pdfIn PDF document text
    • http://bowie.abwingsmd.com/uploads/files/wetakuxalik.pdfIn PDF document text
    • http://explosivedevices.ru/media/file/xolimugisinasufesepofib.pdfIn PDF document text
    • https://tavio.ru/files/file/63211771588.pdfIn PDF document text
    • https://harpethvalleypto.org/wp-content/plugins/super-forms/uploads/php/files/4b43f686e11aaddde0ddcc1931c480ce/mozabujuvof.pdfIn 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://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_off0000afca.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xAFCA 10360 bytes
SHA-256: 97125e8732422ccc98b9f5b097da3e5f8edd0cf4913428a19d68d3dbc5038469
font_01_sfnt_off0000c758.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xC758 14808 bytes
SHA-256: c8821e4e000f5526991f558df9d799e705f6210ed10ba0cb80c484b23076e74d
font_02_sfnt_off0000ec69.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xEC69 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1