Malicious PDF — malware analysis report

Static analysis result for SHA-256 efa00c8a6bbae0d9…

MALICIOUS

PDF

84.8 KB Created: 2021-09-18 22:59:32 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-11-20
MD5: 049ddddf555fd42e982f4b25019abfea SHA-1: 0bc37f34f2d66a72339baa89a9742abad3e57b70 SHA-256: efa00c8a6bbae0d9911d4699a09e3a1da018039d025666c7f79489a174e0be7f
154 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment

The PDF contains embedded JavaScript and numerous external URLs, many of which are hosted on disposable domains, indicating a link farm designed to redirect users. The heuristic 'PDF_SEO_DISPOSABLE_LINK_FARM' and the ClamAV detection 'Pdf.Phishing.Trojan-d2528dad23a95d95-d2528dad23a95d95-10044376-0' strongly suggest malicious intent. The embedded JavaScript likely facilitates the redirection or further payload delivery.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9912

Heuristics 7

  • ClamAV: Pdf.Phishing.Trojan-d2528dad23a95d95-d2528dad23a95d95-10044376-0 critical CLAMAV_DETECTION
    ClamAV detected this file as malware: Pdf.Phishing.Trojan-d2528dad23a95d95-d2528dad23a95d95-10044376-0
  • 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.
  • Callback phishing phone lure medium SE_CALLBACK_LURE
    Document asks the user to call a phone number in billing, refund, subscription, fraud, or security context — consistent with callback phishing or tech-support scam patterns. Suppressed for legitimate-issuer (IRS/gov/official-form) documents that carry no urgency or charge/dispute escalation.
  • 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://synerhu.ru/uplcv?utm_term=game+prototype+android PDF link annotation
    • https://www.ventisilva.com.br/ckfinder/userfiles/files/togokepokiriwud.pdfIn PDF document text
    • https://sainaudit.mn/File/26238038082.pdfIn PDF document text
    • https://textolinguisticsolutions.com/upload/editor/file/kofevepewifike.pdfIn PDF document text
    • https://viktorina.ledoritulys.lt/files/29947810439.pdfIn PDF document text
    • http://dmkert.hu/files/file/98218108194.pdfIn PDF document text
    • http://bezagsecurity.cz/userfiles/jowikuvelidopuxuvuvoj.pdfIn PDF document text
    • http://all-premium.com/user_file/files/14154318008.pdfIn PDF document text
    • http://euroambulans.pl/userfiles/file/14233569493.pdfIn PDF document text
    • http://hig-hegmann.de/userfiles/file/karud.pdfIn PDF document text
    • https://teplitsyoptom.ru/wp-content/plugins/super-forms/uploads/php/files/5019e7cceab422e16f31db519cf4904d/lawebakamefusediz.pdfIn PDF document text
    • http://benetworkingpro.com/ckfinder/userfiles/files/93602438808.pdfIn PDF document text
    • https://mk-sito.it/uploads/file/zijuxetupezawosizi.pdfIn PDF document text
    • http://www.vnos.vn/app/webroot/uploads/files/razovunutikirabuxonisi.pdfIn PDF document text
    • http://kpghomerepairs.com/uploads/image/files/zonijijijemetafafiw.pdfIn PDF document text
    • https://phukienbep.net/media/files/samurujolot.pdfIn PDF document text
    • https://korovin.org/site/img_ufiles/17673530800.pdfIn PDF document text
    • https://www.unicodesystems.com/wp-content/plugins/super-forms/uploads/php/files/ns7lf66lff6lgandqqendpu2q0/felowusuvivejetapagemuli.pdfIn PDF document text
    • https://gornjastubica.hr/files/tiputazomuliruwupesavopu.pdfIn PDF document text
    • http://girlstown.org/files/js/ckfinder/userfiles/files/doxuvaxarot.pdfIn PDF document text
    • http://mindentudor.hu/userfiles/file/44095660458.pdfIn PDF document text
    • http://www.sudeshnamaulik.com/fckimages/file/vapalu.pdfIn PDF document text
    • https://art4you.sk/editor_uploads/system/files/33902712434.pdfIn PDF document text
    • http://bonezi.morefriendship.com/upload/files/fafadipadom.pdfIn PDF document text
    • https://coherence.cz/userfiles/file/98236110664.pdfIn PDF document text
    • http://15441707.com/data/board/file/20210919013530.pdfIn PDF document text
    • http://mamnonsaokhue.vn/app/webroot/files/ckfinder/files/19109249525.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_off0000e443.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xE443 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
font_01_sfnt_off0000fc5a.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xFC5A 10492 bytes
SHA-256: cf36939b22f1d1e9311d30f6d5944093dc53b5452fe9da6d3f50e7ff51b40b91
font_02_sfnt_off00011429.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x11429 18628 bytes
SHA-256: 072f56ab1c09f10abfcb6c3801a2cdf4540e3d1217a569017b455950c047008d