Malicious PDF — malware analysis report

Static analysis result for SHA-256 f3e16767ac94da61…

MALICIOUS

PDF

68.1 KB Created: 2021-09-20 14:50:42 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-10-14
MD5: 31cee668b249cf6ddb798090bef73db9 SHA-1: 99812389ac6f0ad4b09f0bed62f9fea4ae45cb2e SHA-256: f3e16767ac94da61b82e39cc21e6910dfb40eb56b0c4ad20a2a7e5899c9466a2
156 Risk Score

Malware Insights

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

The PDF contains a large number of embedded URLs, many of which point to disposable or compromised hosting domains, indicating a link farm designed to redirect users. The ML classifier and ClamAV detection strongly suggest malicious intent, likely phishing or malware distribution. No scripts were extracted, but the structure and URL patterns are consistent with a malicious PDF dropper.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9966

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://jokerprod.net/userfiles/file/muxipasiroxudaxaboteko.pdf In PDF document text
    • http://vinczeandlaszlo.com/upload/533251841.pdfIn PDF document text
    • http://www.alfapilates.pl/upload/file/24184152268.pdfIn PDF document text
    • https://braviengenharia.com.br/wp-content/plugins/super-forms/uploads/php/files/4g3g82e280m0j0ukauoqsk522o/36778602200.pdfIn PDF document text
    • http://anthonyvienna.com/sites/default/files/file/xenokaluxifaguboturaderep.pdfIn PDF document text
    • https://grupa-energia.pl/attachments/file/wepegibopenuxugiruw.pdfIn PDF document text
    • https://pottoka.info/files/galeria/files/jetokosixevinoxi.pdfIn PDF document text
    • http://es-manzokudou.com/yamituki-n/uploads/files/24667263943.pdfIn PDF document text
    • http://fatfailogistics.com/fckeditor/files/file/13110506638.pdfIn PDF document text
    • http://studiopignotti.it/userfiles/files/85070366737.pdfIn PDF document text
    • http://amirafouad.com/uploaded_files/file/xafuzesa.pdfIn PDF document text
    • http://jamoncup.es/wp-content/plugins/formcraft/file-upload/server/content/files/161404a627579a---bufuzax.pdfIn PDF document text
    • https://fainitelecommunication.com/public/editorfiles/file/99652462158.pdfIn PDF document text
    • http://sm.ac.th/ckfinder/userfiles/files/21248009702.pdfIn PDF document text
    • http://suurelepa.ee/data/file/48977862185.pdfIn PDF document text
    • http://xn--ob0bjxt9h99icicrvkksa421cwwp7hiv4d6a.net/ckfinder/userfiles/files/mavujezorozuronoba.pdfIn PDF document text
    • https://www.auto-ecole-acm.com/ckfinder/userfiles/files/fagisiwopinazozejezorur.pdfIn PDF document text
    • http://ilturismoinitalia.it/userfiles/files/famuxazu.pdfIn PDF document text
    • http://haiqi-machine.com/d/files/52225152191.pdfIn PDF document text
    • http://lubrifianti-auto.ro/files/file/39057261707.pdfIn PDF document text
    • https://velvetskin.pl/wp-content/plugins/super-forms/uploads/php/files/456a4f24331e815b522fd94629a55236/xetunuzegotam.pdfIn PDF document text
    • http://kiiga.ru/userfiles/file/kikitutigi.pdfIn PDF document text
    • https://feedproxy.google.com/~r/Uplcv/~3/S30rS-6n6vg/uplcv?utm_term=other+files+in+internal+storagePDF 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_off0000af12.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xAF12 10516 bytes
SHA-256: 91fa80ccac6d358db65961dca3011b7988b16965f418e60994ba697c414651ce
font_01_sfnt_off0000c6fb.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xC6FB 14484 bytes
SHA-256: 8d6474cad55a5d7d702a8c777eda56c6ec413b3739e172835ad75443776a07a9
font_02_sfnt_off0000eb24.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xEB24 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1