Malicious PDF — malware analysis report

Static analysis result for SHA-256 cb51fd7566edc15d…

MALICIOUS

PDF

73.6 KB Created: 2021-09-17 18:21:43 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-10-24
MD5: d1ddb01cf0dc8600b9511fb46a450e20 SHA-1: 1f6c0cfd6ac28cb6e05ca562a0c1c070765219ac SHA-256: cb51fd7566edc15d3f49988b73a4fd68e9cae2355aafec7b324377781274adf8
164 Risk Score

Malware Insights

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

The file is identified as malicious by ML classifiers and ClamAV, indicating a high likelihood of malicious intent. Numerous URLs are present, many pointing to potentially compromised or disposable hosting, suggesting a link farm designed to redirect users to malicious content. The presence of a 'download button' heuristic further supports the lure-based attack pattern.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9991

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.
  • Visual download / call-to-action button lure low SE_DOWNLOAD_BUTTON
    Document contains a call-to-action phrase ('Click here to download', 'Download Now', etc.) — low-signal unless other findings point to a malicious workflow
  • 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://huntic.ru/uplcv?utm_term=windows+10+pro+64+bit+iso PDF link annotation
    • http://digitalqwerty.com/ckfinder/userfiles/files/81649287770.pdfIn PDF document text
    • http://emeraldcovepartners.com/_data/images/file/64582453655.pdfIn PDF document text
    • https://kltccompany.com/ckfinder/userfiles/files/poxesotaliwajujovufevowax.pdfIn PDF document text
    • http://j-club.eu/userfiles/file/70490051573.pdfIn PDF document text
    • http://brodart01.com/wp-content/plugins/super-forms/uploads/php/files/3r5kmg9hpf24hbka5fdedtf54k/kizakeluvewupokukesapim.pdfIn PDF document text
    • https://siriusdynamics.com/assets/uploads/files/boximu.pdfIn PDF document text
    • https://ewt.cz/res/file/41643859682.pdfIn PDF document text
    • http://agcslohian.com/userfiles/file/xasufesegemukadabi.pdfIn PDF document text
    • https://imapcb.org/wp-content/plugins/super-forms/uploads/php/files/7ce8a9400ed513513853e3a4011c01a8/jetipasarajafewiguxelo.pdfIn PDF document text
    • http://bernardthevenet.fr/ckfinder/userfiles/files/dexabutugavipan.pdfIn PDF document text
    • https://burstallconrad.com/editor_files/file/zafegemoxulotunugit.pdfIn PDF document text
    • https://glbtrader.com/userfiles/file/51585683774.pdfIn PDF document text
    • http://rsport.eu/yonexshop/static/file/zofufivapebuzomidur.pdfIn PDF document text
    • http://www.ebsjosepirosamaria.com/wp-content/plugins/formcraft/file-upload/server/content/files/1613cee436dc85---93713994654.pdfIn PDF document text
    • http://rhondachem.com/d/files/28599010652.pdfIn PDF document text
    • https://globalathena.com/ckfinder/userfiles/files/72241643667.pdfIn PDF document text
    • http://zh-huaxun.com/uploadfiles/files/sovonubotafimivav.pdfIn PDF document text
    • http://sinostandards.net/upload/files/81549550795.pdfIn PDF document text
    • http://uniondeautoescuelas.com/wp-content/plugins/formcraft/file-upload/server/content/files/1613e01d7d524f---jijaxil.pdfIn PDF document text
    • http://pushgroup.lv/userfiles/files/83218723377.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_off0000bd9b.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xBD9B 16632 bytes
SHA-256: 3ce156b9f2b6cdcab1a7aa10e7b0befb542b353bfe147dfdc79703b120326d84
font_01_sfnt_off0000e8aa.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xE8AA 10684 bytes
SHA-256: 9fdd2e276ba53f6aa7cdb0e224304e8db1c5de2ea23b00d3cefb806464049d3a
font_02_sfnt_off00010123.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x10123 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1