Malicious PDF — malware analysis report

Static analysis result for SHA-256 5df7f7db6c9e8f97…

MALICIOUS

PDF

81.7 KB Created: 2021-09-04 21:18:18 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-10-16
MD5: 12cd3dec046e9a10e40b9ef8bfd02ab1 SHA-1: 14c40975eefd3a5a8160c826eca706b3530786f3 SHA-256: 5df7f7db6c9e8f97fc02e9c469c80e9dc5c759c6891d0c36418141b9c13b6626
156 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment T1204.002 Malicious Link

The PDF file was flagged by ML classifiers and ClamAV as malicious, specifically as a phishing trojan. It contains numerous external URIs and link farms pointing to compromised CMS uploads and disposable hosting, indicating an attempt to redirect users to malicious sites. The document body is heavily obfuscated and unreadable, suggesting it is designed to conceal its malicious intent.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9985

Heuristics 6

  • 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.
  • 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://crysiq.ru/uplcv?utm_term=hamiltonian+systems+and+their+integrability+pdf PDF link annotation
    • http://abnicum.ru/files/file/22955113965.pdfIn PDF document text
    • https://china-glass-mosaic.com/userfiles/files/20210731_230306.pdfIn PDF document text
    • https://ontime-taxi.kg/wp-content/plugins/super-forms/uploads/php/files/c63596332bdbcc58291c318809c76361/5453046493.pdfIn PDF document text
    • http://ottotech.center/userfiles/file/2435822948.pdfIn PDF document text
    • https://profix.fr/ckfinder/userfiles/files/62905718318.pdfIn PDF document text
    • http://www.consorcio.edu.pe/wp-content/plugins/formcraft/file-upload/server/content/files/161239c863a3a0---9498062046.pdfIn PDF document text
    • https://csom.cz/wp-content/plugins/super-forms/uploads/php/files/a0ea30c8690c1c907eec69b33f1efb64/50033477608.pdfIn PDF document text
    • http://chayka-svg.ru/files/xajuxodafuvirumebaburor.pdfIn PDF document text
    • http://absolutelyneon.com/userfiles/file/24566470253.pdfIn PDF document text
    • http://comicpapyrus.com/wp-content/plugins/super-forms/uploads/php/files/c04328fe88e03fce555075013b5ce1c4/71846325746.pdfIn PDF document text
    • http://www.veronicaneal.com/wp-content/plugins/formcraft/file-upload/server/content/files/1/160ac8175e9b6d---zonexewiwo.pdfIn PDF document text
    • http://netmode.net/app/webroot/uploads/files/mexusa.pdfIn PDF document text
    • https://tamphuctriland.vn/upload/files/latonivifuzun.pdfIn PDF document text
    • http://www.klpreschool.com/wp-content/plugins/formcraft/file-upload/server/content/files/1607252d4822f9---89053852570.pdfIn PDF document text
    • http://bfr-bialapodlaska.pl/userfiles/file/zagikojepukoximadurupuki.pdfIn PDF document text
    • https://rsun.pro/admin/ckfinder/userfiles/files/vifor.pdfIn PDF document text
    • https://velvetskin.pl/wp-content/plugins/super-forms/uploads/php/files/f84c35885a1b5205ddfb31b6874a0a0d/zasivaxolirojumiva.pdfIn PDF document text
    • https://mosoptagro.ru/wp-content/plugins/super-forms/uploads/php/files/3b5254f0739d1805b377c10c53f3c83f/latadilebu.pdfIn PDF document text
    • http://tourister.kr/userfiles/file/zabafazobigotad.pdfIn PDF document text
    • https://cls-toronto.com/wp-content/plugins/super-forms/uploads/php/files/af73620c4f262a5045641ad1f6d02e9a/50858492047.pdfIn PDF document text
    • http://duonglaohanoi.com/userfiles/file/61578530982.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_off0000d2ee.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xD2EE 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
font_01_sfnt_off0000eb05.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xEB05 11192 bytes
SHA-256: 1f933c81ba6e9964f2b81ebd4fae2dde57d54af5265d820f417dcc701e2390f0
font_02_sfnt_off00010482.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x10482 19688 bytes
SHA-256: 28a7606d59b1a242b266dc8627c7d9ff37b371efa013ad60091172bd06f603ab