Malicious PDF — malware analysis report

Static analysis result for SHA-256 9321bdefb89147e6…

MALICIOUS

PDF

92.4 KB Created: 2021-09-13 17:22:31 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3)
MD5: 98a3572813ecf6b196e20fd37e771928 SHA-1: 5c835bdbe2349a735e1cc7f5b36a569c4ebbc83e SHA-256: 9321bdefb89147e64302991ab56f54de1f8b6da0d9e7c3f934b2199212b5bb30
196 Risk Score

Malware Insights

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

This PDF document was flagged by multiple heuristics and a machine learning classifier as malicious, specifically as a phishing lure. The document's content, though heavily obfuscated, suggests a social engineering tactic to trick users into installing a browser extension or update. Several external URLs were extracted, many pointing to compromised WordPress sites, indicating a potential distribution network for malicious content.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9977

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
  • Browser extension / update installation lure high SE_BROWSER_INSTALL_LURE
    Document tells the user to install a browser extension, plugin, viewer, or browser update to view content — a common social-engineering path for credential theft and malware installation
  • 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://coretry.ru/uplcv?utm_term=packet+capture+apk
    • https://www.gs-gleichmann.de/wp-content/plugins/formcraft/file-upload/server/content/files/16137cac25137b---67251031886.pdf
    • http://hydrem.ru/images/file/72522247676.pdf
    • https://t4g.nasscomfoundation.org/wp-content/plugins/super-forms/uploads/php/files/ifjq23kt2e7l1p5il6r15hlbo0/ruvagenoladakoji.pdf
    • https://jagamimpi.net/contents/files/mijeribiladen.pdf
    • http://aarogyamedico.com/userfiles/file/pazorulilaropavuwatut.pdf
    • https://kstraders.com/userfiles/file/gopojit.pdf
    • http://elandtour.com/FileData/ckfinder/files/20210910_11FA4EF1C2418562.pdf
    • http://costanzolegal.com/customer/3/d/9/3d947ad6ce2568d98b832ccf5548371bFile/71004930682.pdf
    • http://azizavacanze.com/userfiles/files/79434680544.pdf
    • http://windcampus.com/wp-content/plugins/formcraft/file-upload/server/content/files/1613b0b5f462e8---jadegi.pdf
    • https://www.bmo-agencement.fr/ckfinder/userfiles/files/57886874133.pdf
    • https://cristalparkhotel.com/ckfinder/userfiles/files/mudoxodem.pdf
    • https://mimpishio2bet.com/contents/files/78709126001.pdf
    • https://noursportevents.com/wheelmarine/userfiles/file/gulugavepumefowus.pdf
    • https://jahanchart.ir/data/files/file/16544559027.pdf
    • http://candientushinko.com/images/file/51497220192.pdf
    • https://otoform.com/upload/ckfinder/files/77846160954.pdf
    • http://www.loockuniformes.com.br/home/wp-content/plugins/formcraft/file-upload/server/content/files/1613b629a0f4c9---riwawupibog.pdf
    • http://www.studiolegalefusimorelli.com/wp-content/plugins/formcraft/file-upload/server/content/files/161348feb83739---27471813921.pdf
    • http://cungcapbaoduongcuanhatban.com/upload/files/75207447728.pdf
    • https://mobspace.xyz/web/img/podborky/files/52819889400.pdf
    • http://xn--80aguejfegacgj0ad.xn--p1ai/pict/file/zegegiwobulovewaboxeluja.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_off0001049b.bin
70930c06345fe36bcf79950de71789c9a4bdc5020cb7276a06ae93b3ff33d98c
pdf-font-stream PDF embedded font (sfnt) at offset 0x1049B 18756 bytes
font_01_sfnt_off0001359a.bin
b90c00826e42dd6dd43e27accfa6b5b2c292c97716b695b8959f03ff611501c1
pdf-font-stream PDF embedded font (sfnt) at offset 0x1359A 10028 bytes
font_02_sfnt_off00014c16.bin
9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
pdf-font-stream PDF embedded font (sfnt) at offset 0x14C16 16792 bytes