Malicious PDF — malware analysis report

Static analysis result for SHA-256 5efd7973f3d44da1…

MALICIOUS

PDF

92.1 KB Created: 2021-07-30 19:06:13 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-10-23
MD5: e951ab07b162802ac34fce92c9e42304 SHA-1: 0ad90c77c5efe1be08227941f365bdacffbd2c6f SHA-256: 5efd7973f3d44da1efa71cb5212867919a1cf2fe7a7301bccedcff058eaa95a5
164 Risk Score

Malware Insights

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

The sample is a PDF document containing embedded JavaScript, which is a common technique for delivering malicious content. It also features a link farm pointing to multiple compromised WordPress sites and disposable hosting, suggesting an attempt to distribute further malware or conduct phishing. The ML classifier and ClamAV detection strongly indicate malicious intent.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9992

Heuristics 7

  • 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.
  • 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://gift-edu.ru/wp-content/plugins/super-forms/uploads/php/files/20905a6afe90e3ac3531a70ce432d9d3/93950980904.pdf In PDF document text
    • http://www.mondzorgvesa-voorschoten.nl/wp-content/plugins/formcraft/file-upload/server/content/files/160a3717cb02be---21297322014.pdfIn PDF document text
    • https://dolaodong.com/userfiles/file/galiv.pdfIn PDF document text
    • http://www.serenissimaservizi.com//files/65097096308.pdfIn PDF document text
    • https://velvetskin.pl/wp-content/plugins/super-forms/uploads/php/files/8d502c8326257999b6d0344401c6e9ff/42871501802.pdfIn PDF document text
    • https://www.paparazzirestaurant.com.au/wp-content/plugins/super-forms/uploads/php/files/3813173021f2d9f77e7ba248d94ffa31/tikigi.pdfIn PDF document text
    • https://kakvkusno26.ru/wp-content/plugins/super-forms/uploads/php/files/be9791b2515ed53ccb3590c5eb94889b/66167264411.pdfIn PDF document text
    • http://vdgairconditioning.nl/wp-content/plugins/formcraft/file-upload/server/content/files/1608b0555719ed---pitimogovagekewetokizoz.pdfIn PDF document text
    • https://stcatherine.ac.ug/wp-content/plugins/formcraft/file-upload/server/content/files/160a7db4f01f92---xijap.pdfIn PDF document text
    • https://www.fmworks.com.tr/wp-content/plugins/super-forms/uploads/php/files/4voosf2mmbdmb9j8t9psbbgpr4/83491607501.pdfIn PDF document text
    • https://www.budgetskemaet.dk/wp-content/plugins/formcraft/file-upload/server/content/files/1608e7f0a163a8---52418449668.pdfIn PDF document text
    • https://40parables.com/wp-content/plugins/super-forms/uploads/php/files/621f0a053db7b7383a95f1c1982ad68d/konigobigojego.pdfIn PDF document text
    • http://rusiuojigalvoji.lt/wp-content/plugins/formcraft/file-upload/server/content/files/160c1f6146164e---kulobirenuw.pdfIn PDF document text
    • https://hondamienbac.vn/userfiles/file/69336277724.pdfIn PDF document text
    • http://www.asslar.de/downloads/20841579361.pdfIn PDF document text
    • https://silatur.com/js/ckfinder/userfiles/files/92936444217.pdfIn PDF document text
    • https://aguiapromocional.com.br/wp-content/plugins/formcraft/file-upload/server/content/files/160aa4107ccf7c---94134974135.pdfIn PDF document text
    • https://alnahamgroup.com/userfiles/file/41978273326.pdfIn PDF document text
    • https://aftaplan.com/works/peepsparty/html/upload_files/file/42697748559.pdfIn PDF document text
    • https://amiablediamonds.com/wp-content/plugins/super-forms/uploads/php/files/6646f39092eafbd3621b852ff6c2d542/44087202842.pdfIn PDF document text
    • https://frennphotography.com/wp-content/plugins/formcraft/file-upload/server/content/files/160f57e12229d7---32046480723.pdfIn PDF document text
    • http://engineersclasses4competition.com/files/others/mifadiwi.pdfIn PDF document text
    • https://feedproxy.google.com/~r/Uplcv/~3/GLLx1DTH0VQ/uplcv?utm_term=how+many+quarts+of+oil+does+a+2017+traverse+takePDF 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_off0000fe29.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xFE29 17672 bytes
SHA-256: 7919ad3d286c7d93211d53b12067ea6c517589cd989ccca805e3990830bf9fd1
font_01_sfnt_off00012cb7.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x12CB7 11452 bytes
SHA-256: f9b87b4f07e9f69fb40a2f15502861ec493da5e33ea25056a58a61658f1419cc
font_02_sfnt_off000147bc.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x147BC 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1