Malicious PDF — malware analysis report

Static analysis result for SHA-256 9a67a8a748a3be8b…

MALICIOUS

PDF

73.3 KB Created: 2021-09-18 16:53:24 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-10-27
MD5: 937827174fdd89bc22576480238472fc SHA-1: 125ae79d10552ef15ed5a48169634a5aac56950a SHA-256: 9a67a8a748a3be8b97f32a417e53e779c69f4480689e11b661f737a533985d1b
126 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment

The sample was identified as malicious by ML classifiers and ClamAV, indicating a high likelihood of malicious intent. The PDF contains numerous embedded URLs, with one heuristic specifically flagging it as a link farm on disposable hosting, suggesting a phishing or malware distribution scheme. While no scripts were directly extracted, the PDF structure and embedded links are indicative of an attempt to redirect users to malicious sites.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9973

Heuristics 5

  • 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.
  • 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://pergamine.com/ckfinder/userfiles/files/jilukiluvudurinakupiza.pdf In PDF document text
    • https://emenu.hu/editor_up/penexapibivumij.pdfIn PDF document text
    • http://www.vnv.nu/admin/library/ckfinder/userfiles/files/49218090096.pdfIn PDF document text
    • https://777mto.com/contents/files/labosegufujakonofobizixif.pdfIn PDF document text
    • http://brmxn.com/userfiles/file/20210901114531_swuw4l.pdfIn PDF document text
    • http://tw-echen.com/uploads/files/202109070649458936.pdfIn PDF document text
    • https://sanagustin.cl/files/23652138831.pdfIn PDF document text
    • https://latework.cz/soubory/87256677362.pdfIn PDF document text
    • https://hardlineconstruct.ro/app/webroot/files/userfiles/files/vezemixakavofupiwotadiku.pdfIn PDF document text
    • http://kaies.cn/upfiles/file/lugesojuxakitarepakikozev.pdfIn PDF document text
    • http://mis.nrru.ac.th/gradjournal/ckfinder/userfiles/files/keluxidupovufox.pdfIn PDF document text
    • https://theipbuzz.com/images/file/ruzajibijawipesevo.pdfIn PDF document text
    • http://dietetyka-24.pl/images/files/wamazisubovekikajetofoxu.pdfIn PDF document text
    • https://tapetcenter.ro/app/webroot/files/userfiles/files/91013165422.pdfIn PDF document text
    • http://imdmotors.com/uploadfile/file/2021090721062179.pdfIn PDF document text
    • http://hcvitamin.com/webroot/img/files/55071767901.pdfIn PDF document text
    • http://locke-3c.tw/uploads/files/202109121347037160.pdfIn PDF document text
    • http://okna-kursk.ru/page_edit/_samples/userfiles/files/pefuzobepubivagux.pdfIn PDF document text
    • https://pfgmm.com.au/wp-content/plugins/formcraft/file-upload/server/content/files/16137c37090306---vigowidototolowusad.pdfIn PDF document text
    • https://fertilizerproductionprocess.com/d/files/xisisubuxilobukixaxinala.pdfIn PDF document text
    • https://greenfuturevietnam.com/Upload/files/54018611482.pdfIn PDF document text
    • http://jsjxh.org/filespath/files/20210901223041.pdfIn PDF document text
    • https://marblobathware.ph/app/webroot/img/files/1811587114.pdfIn PDF document text
    • http://premiumcsp.com/uploads/files/fuvad.pdfIn PDF document text
    • https://www.domosystem.gr/ckfinder/userfiles/files/xoboxexekidoweva.pdfIn PDF document text
    • https://feedproxy.google.com/~r/Uplcv/~3/DOqCt-cVA4I/uplcv?utm_term=remove+password+on+phonePDF 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_off0000bd69.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xBD69 16324 bytes
SHA-256: f775601d3c19a7a6d41860fa3c6f37c3ae10d74bd12e0e18b5136431c2f4ea2c
font_01_sfnt_off0000e747.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xE747 10616 bytes
SHA-256: cc633e30821eb6850600507b071736e0262404897e725dbd93fd94d5aa0e8acb
font_02_sfnt_off0000ff64.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xFF64 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1