Malicious PDF — malware analysis report

Static analysis result for SHA-256 5019883871881b7e…

MALICIOUS

PDF

67.8 KB Created: 2021-04-28 07:44:26 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 4.8.7) First seen: 2021-06-17
MD5: b5c76a7db44a98df15bce89724d108db SHA-1: 471166ae2a9adfd9a65d6add96b932dde25a7574 SHA-256: 5019883871881b7ec04de6ce23c99764896c3e1cce4e625dfdf7cc31b4383adc
156 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment T1204.002 User Execution: Malicious File

The PDF file was detected as malicious by ML classifiers and ClamAV, specifically identified as a phishing trojan. It contains a link farm pointing to numerous compromised WordPress sites, suggesting an attempt to distribute malicious content or conduct phishing. The document body is heavily obfuscated and appears to be a lure, with the primary malicious activity being the redirection to external, compromised URLs.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9998

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://ziepniekkalns.lv/wp-content/plugins/formcraft/file-upload/server/content/files/16082a98bc8e5e---wenumo.pdf In PDF document text
    • http://drvision.org/wp-content/plugins/formcraft/file-upload/server/content/files/160730b5fea18d---66914080434.pdfIn PDF document text
    • http://dangkyidol.com/wp-content/plugins/super-forms/uploads/php/files/rurfub2cs32j4d9nchqba74a2j/13509989420.pdfIn PDF document text
    • http://www.majorisinvestimentos.com.br/wp-content/plugins/formcraft/file-upload/server/content/files/1608441f37b422---feragekirexuse.pdfIn PDF document text
    • https://maxim-catering.de/wp-content/plugins/super-forms/uploads/php/files/287dka0a18odugks2elbem7eqg/siwazesagiratolexuseputad.pdfIn PDF document text
    • https://akapacha.com/userfiles/file/kexukavatubulelesixo.pdfIn PDF document text
    • http://admio.ru/wp-content/plugins/formcraft/file-upload/server/content/files/160762dddc309d---34686117231.pdfIn PDF document text
    • http://hellnocancershow.com/wp-content/plugins/formcraft/file-upload/server/content/files/16081881496c72---82139666023.pdfIn PDF document text
    • https://drmiamiconnect.com/wp-content/plugins/super-forms/uploads/php/files/ae9fc7934b5113a7d4136b37ff3a7620/421486412.pdfIn PDF document text
    • https://atolab.it/wp-content/plugins/super-forms/uploads/php/files/ec40cba472fa7fbc9f0a0fcd65587b7c/9403587533.pdfIn PDF document text
    • https://ailani.org/wp-content/plugins/super-forms/uploads/php/files/301444b2b1de978886d2e79d1a9f9cdc/gobejufexozizem.pdfIn PDF document text
    • https://shining4u.com/wp-content/plugins/super-forms/uploads/php/files/0b1da172060d1607cbeed6fa9a61bc0b/84203251890.pdfIn PDF document text
    • http://ganan10.co.il/wp-content/plugins/formcraft/file-upload/server/content/files/160719328e3d01---90231062810.pdfIn PDF document text
    • http://steclotildehorton.ca/wp-content/plugins/formcraft/file-upload/server/content/files/1607924453a85f---36577911188.pdfIn PDF document text
    • https://wholisticvibrations.com/wp-content/plugins/super-forms/uploads/php/files/333b0b72718b0e8ea80118cac47ec7e6/sigowekakajagosurolu.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/1eyvgo/aqOO/~3/6naE_Nh8_CY/uplcv?utm_term=snake+food+size+guidePDF 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

Extracted artifacts 2

Files carved from inside the sample during analysis.

FilenameKindSourceSize
font_00_sfnt_off0000ce6c.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xCE6C 5164 bytes
SHA-256: b896dc910f41af05d6d690677539edf018a16012714d9c8a96dafe5309b64223
font_01_sfnt_off0000e023.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xE023 10100 bytes
SHA-256: 5dd3e7176de0178c6f561030bed53506dc0b0af93060c1a5200699c6ca49064f