Malicious PDF — malware analysis report

Static analysis result for SHA-256 99b444a99ee9284a…

MALICIOUS

PDF

140.7 KB Created: 2021-09-15 14:59:39 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-10-16
MD5: 6bf023ff0107366fa32933470bfba516 SHA-1: 9c0b95e6d718033d45116d2a9a6ba83d3d32e81c SHA-256: 99b444a99ee9284a33490d57150bd016bba6ca5f0545b52ce4591296f83a6127
164 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment

The PDF contains embedded JavaScript, which is a common technique for executing malicious code within documents. The presence of numerous external URIs, including links to compromised CMS uploads and disposable hosting, strongly suggests a phishing or malware distribution attempt. The ML classifier and ClamAV detection further corroborate the malicious nature of this file.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9922

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://baxsporthorses.nl/userfiles/file/rafogo.pdf In PDF document text
    • http://www.palmettoexpresslanes.com/system/js/back/ckfinder/userfiles/files/jewalosojet.pdfIn PDF document text
    • https://pcetravel.com/files/file/29959164731.pdfIn PDF document text
    • http://agedwedfjtj.pretty-match.com/upload/files/gugix.pdfIn PDF document text
    • http://csc0532.com/userfiles/file/20210904072921_12tklt.pdfIn PDF document text
    • http://pk-rowery.pl/user_pict/file/rutawebul.pdfIn PDF document text
    • http://gaudi.tw/upload/files/pabifurikipebexaguzoge.pdfIn PDF document text
    • https://srilangkapools.com/contents/files/lipuvitujepoku.pdfIn PDF document text
    • https://tapetcenter.ro/app/webroot/files/userfiles/files/lagizasilajoto.pdfIn PDF document text
    • https://lyna-garage.com/htdocs/cljr/data/files/26512900424.pdfIn PDF document text
    • https://perfecthospitals.com/ckfinder/userfiles/files/wusadutakozidu.pdfIn PDF document text
    • https://defrokatilai.lt/images/files/78263253289.pdfIn PDF document text
    • https://altaamir.ipixpms.com/Rapport/public/assets/ckfinder/userfiles/files/45221807099.pdfIn PDF document text
    • https://xn-----6kcabagcgfjsxjciriy6alkh6a7aqk.xn--p1ai/wp-content/plugins/super-forms/uploads/php/files/ccfa1986ecf6f5a2696fd4247739e444/34716999615.pdfIn PDF document text
    • http://shsuorui.com/uploadfiles/fckeditor/20210910/file/16312331518178.pdfIn PDF document text
    • https://www.emmabowman.com/wp-content/plugins/super-forms/uploads/php/files/d3ee78f1bc5890db43ba41f82d133508/50608203271.pdfIn PDF document text
    • http://rowadhr.com/app/webroot/upload/files/xofujatakijibifoxu.pdfIn PDF document text
    • http://pravkniga.ru/files/userfiles/files/98288270371.pdfIn PDF document text
    • http://cjmfgxfollow.morefriendship.com/upload/files/52009330907.pdfIn PDF document text
    • https://stcc-sa.com/motakamel/Ups/files/76870771231.pdfIn PDF document text
    • https://giaphutelecom.com/tctt/sites/aaa/file/gonawotitagojeliwezo.pdfIn PDF document text
    • http://ipvoicenj.com/wp-content/plugins/formcraft/file-upload/server/content/files/161393d90d2ad8---63057223937.pdfIn PDF document text
    • http://centroolosprato.it/userfiles/files/fomeneta.pdfIn PDF document text
    • https://feedproxy.google.com/~r/1eyvgo/aqOO/~3/zMnd8XtcwSM/uplcv?utm_term=professional+english+for+commerce+and+management+guide+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_off0001b8d3.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x1B8D3 22012 bytes
SHA-256: bdce3aac314efb51b4d348f7042753928b8ec0fb25376c120cee0dfbc01da8ea
font_01_sfnt_off0001f271.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x1F271 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
font_02_sfnt_off00020a88.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x20A88 11168 bytes
SHA-256: 722a7b2ded5d53e593cf14b2f6b628c93bc2cca7fcd42b0a72df56708a9b5bce