Malicious PDF — malware analysis report

Static analysis result for SHA-256 1beec84a79d98cef…

MALICIOUS

PDF

79.8 KB Created: 2021-09-19 13:21:25 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3)
MD5: 4da3cae8a2b083940164bf0c3fb9f10e SHA-1: 8a21ba97d3b6ccce43a4ba616dca39eba6484abf SHA-256: 1beec84a79d98cefc1d3e98ed3a9f6f95bba710b16a0e03eb16bc2d5705d77fa
164 Risk Score

Malware Insights

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

The sample is a PDF file flagged by ClamAV as a phishing trojan and a machine learning classifier. It contains numerous links to external websites, many of which are hosted on compromised or disposable domains, suggesting a link farm designed to redirect users to malicious content. The presence of a 'download button' heuristic further supports the phishing lure attack pattern.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9975

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://synerhu.ru/uplcv?utm_term=browser+unblock+apk
    • http://zsdbiopharm.com/upload/files/netedifenekuli.pdf
    • https://simon-daulte.com/ckfinder/userfiles/files/31237791627.pdf
    • http://kanchanaspa.com/ckfinder/userfiles/files/15760953391.pdf
    • http://sorokolaw.com/customer/3/d/9/3d947ad6ce2568d98b832ccf5548371bFile/43637154316.pdf
    • http://ty6600.com/userfiles/file/fajujizelupoduxu.pdf
    • http://trunglam.vn/uploads/userfiles/file/5978635182.pdf
    • http://forumcutuca.com/ckfinder/userfiles/files/tudizov.pdf
    • https://www.hotelamoha.it/wp-content/plugins/formcraft/file-upload/server/content/files/161348639b669e---josarexasegibiwanosu.pdf
    • https://reclamesticker.nl/images/uploads/file/
    • http://www.sunaryem.com.tr/wp-content/plugins/super-forms/uploads/php/files/t3e7edqp6en94lqsa5f1apl284/lepexagoba.pdf
    • http://textstricker.de/benutzerdateien/62554258043.pdf
    • http://pyhunlian.com/uploadfile/file/24567594589.pdf
    • https://ferado.vn/userfiles/file/kadarenamasupokukupew.pdf
    • http://www.radeton-cz.vasestranky.cz/ckfinder/userfiles/files/36194379975.pdf
    • https://bwhe.in/ckfinder/userfiles/files/mapikaxogemeje.pdf
    • https://vr-spagna-20.effievirtual.com/galeria/files/89450523993.pdf
    • http://ahzgbh.news-read.com/upload/files/kuxax.pdf
    • http://3mfa.com/images/editor/files/rudiwamekokur.pdf
    • http://turinhotelcompany.com/userfiles/files/70960124176.pdf
    • https://thietbivesinhsonhoa.com/webroot/img/files/40041889434.pdf
    • https://office-agglo-larochelle.fr/userfiles/file/13437605352.pdf
    • https://web-sila.ru/wp-content/plugins/super-forms/uploads/php/files/0cd5a08f476ecee66bbfb9faffa1fe6b/91763007564.pdf
    • https://milosislandrooms.gr/userfiles/file/24478437161.pdf
    • https://printsolutions.printsolutions.bg/uploads/wysiwyg/files/54697897798.pdf
    • http://www.w3.org/1999/02/22-rdf-syntax-ns#
    • http://purl.org/dc/elements/1.1/
    • http://ns.adobe.com/pdf/1.3/
    • http://ns.adobe.com/xap/1.0/
    • http://ns.adobe.com/xap/1.0/mm/
    • http://ns.adobe.com/xap/1.0/rights/
    • http://dejavu.sourceforge.net
    • http://dejavu.sourceforge.net/wiki/index.php/License

Extracted artifacts 3

Files carved from inside the sample during analysis.

FilenameKindSourceSize
font_00_sfnt_off0000d1d6.bin
209f025516cf94b385fcfeec5c08b5212e158bf9d2778b53e877f9c4c109c87b
pdf-font-stream PDF embedded font (sfnt) at offset 0xD1D6 18296 bytes
font_01_sfnt_off0001013b.bin
9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
pdf-font-stream PDF embedded font (sfnt) at offset 0x1013B 16792 bytes
font_02_sfnt_off00011952.bin
4b2448cc1b9639ef48ddfab44c2808c00b9faf73dd34bcb07be82f8ad9cb6092
pdf-font-stream PDF embedded font (sfnt) at offset 0x11952 10648 bytes