Malicious PDF — malware analysis report

Static analysis result for SHA-256 f951aa4af1f5d6b2…

MALICIOUS

PDF

69.2 KB Created: 2021-09-27 07:17:12 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-11-02
MD5: fd8f4e4fe59f3b205a3a10a7ccdf55e2 SHA-1: 3d07d63f5c0a8792d6d51cf5b1a792c79eff7f51 SHA-256: f951aa4af1f5d6b2ce18558342d8184072a92e8b87a0b848297a048c21210978
126 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment T1203 Exploitation for Client Execution

The PDF file was flagged by ML classifiers and ClamAV as malicious, specifically as a phishing trojan. Heuristics indicate it functions as a link farm, containing numerous embedded URLs pointing to potentially malicious or deceptive content. The document body is heavily obfuscated and unreadable, suggesting an attempt to hide its true purpose.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9951

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://highlander-inn.com/assets/userfiles/files/44766217804.pdf In PDF document text
    • http://xaydungphongphu.com/uploads/files/52633230364.pdfIn PDF document text
    • http://syntra.pl/userfiles/file/18949652055.pdfIn PDF document text
    • https://cbdc.co/uploads/ckfinder/userfiles/files/36363556718.pdfIn PDF document text
    • http://www.aceitunasdelguadalhorce.es/ckfinder/userfiles/files/37275064431.pdfIn PDF document text
    • https://lasanisports.com/files/venodoxumara.pdfIn PDF document text
    • http://naoshima-tours.com/images/blog/file/mokarizil.pdfIn PDF document text
    • http://posekatzahradu.cz/files/file/84944097724.pdfIn PDF document text
    • http://aire-limpio.com/img/editor/file/78253751669.pdfIn PDF document text
    • http://inarchengineering.it/userfiles/files/kinusosiwase.pdfIn PDF document text
    • https://vegan-eshop.cz/data/file/womiwiwefanusopuwuveniv.pdfIn PDF document text
    • http://abnicum.com/files/file/jokatut.pdfIn PDF document text
    • http://sinosteelcode.com/filespath/files/20210927115559.pdfIn PDF document text
    • http://brenna-ski.pl/userfiles/file/17395648427.pdfIn PDF document text
    • https://danfort.lv/userfiles/file/84907972667.pdfIn PDF document text
    • https://hv2barrier.com/application/third_party/ckfinder/userfiles/files/73675244161.pdfIn PDF document text
    • http://baoveantam.org/upload/files/tazexixa.pdfIn PDF document text
    • http://jyjwqj.com/uploadfile/file///2021091917114318.pdfIn PDF document text
    • https://rasathantrananotech.com/ckfinder/userfiles/files/19866421112.pdfIn PDF document text
    • https://ercrs.org/wp-content/plugins/super-forms/uploads/php/files/tj2ivgi29fuq0kp8kbt4shj64a/jepajemope.pdfIn PDF document text
    • http://mengnuanua.com/app/webroot/files/files/tegozirovo.pdfIn PDF document text
    • http://bookblog.kr/data/file/files/35708934808.pdfIn PDF document text
    • https://pemaboutiquehotel.com/assets/userfiles/files/61072440888.pdfIn PDF document text
    • http://www.rannatennis.ee/data/upfiles/files/vukajawiw.pdfIn PDF document text
    • https://feedproxy.google.com/~r/Uplcv/~3/3vuEKuznOb8/uplcv?utm_term=how+to+use+android+on+windows+10PDF 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_off0000aff1.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xAFF1 15644 bytes
SHA-256: fee195d0efaaf1da51fd20e6acc59868edba231b724f66d38fac8e27e15188fb
font_01_sfnt_off0000d755.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xD755 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
font_02_sfnt_off0000ef6c.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xEF6C 10548 bytes
SHA-256: 35a139587dc56eead0d926d84279d71f068700635cbce8342fed0cf2eb01e761