Malicious PDF — malware analysis report

Static analysis result for SHA-256 a8cce1b8c61aaeac…

MALICIOUS

PDF

106.9 KB Created: 2021-09-06 05:51:01 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3)
MD5: 6631d33e2775eecb78d46dbc65194ab3 SHA-1: 8abde44a930980af0589858569cd241d928045ce SHA-256: a8cce1b8c61aaeac283a2d0ae98dbe957ff7afb9fbb70b7b093ee7e58d4bde83
244 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment T1204.002 User Execution: Malicious File

The PDF contains embedded JavaScript and numerous external links, many pointing to compromised WordPress sites or disposable hosting, suggesting a phishing or malware distribution attempt. The heuristics indicate a lure to install browser extensions/updates and a password-protected archive, likely to bypass security controls and trick the user into executing a malicious payload. The ML classifier and ClamAV detection strongly support its malicious nature.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9958

Heuristics 9

  • ClamAV: Pdf.Phishing.Trojan-d2568dad23a94d95-d2568dad23a94d95-10044375-0 critical CLAMAV_DETECTION
    ClamAV detected this file as malware: Pdf.Phishing.Trojan-d2568dad23a94d95-d2568dad23a94d95-10044375-0
  • Password-protected archive handoff high SE_PASSWORD_ARCHIVE_LURE
    Document gives password instructions for an archive or attachment — often used to keep payloads encrypted until after gateway scanning
  • 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.
  • Embedded JS stream low PDF_JS
    PDF references a /JS stream. Generic JavaScript is common in benign forms; specific dangerous APIs are scored by separate rules.
  • 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 http://geologocarmignani.com/userfiles/files/boxesabaludo.pdf
    • https://outsourcedbackoffice.co.uk/wp-content/plugins/super-forms/uploads/php/files/e263067098c526db50212adfd506e552/50533624622.pdf
    • https://licorne-hotel-restaurant.com/userfiles/file/vijoleroreporajurixara.pdf
    • http://chrislahoda.ca/userfiles/file/98776573623.pdf
    • http://www.aqsclimited.com/EditorImages/file/sizuvawegam.pdf
    • http://www.realisthotel.com/wp-content/plugins/formcraft/file-upload/server/content/files/160a3145f2c439---tuwuvaropoxadenatul.pdf
    • https://afayl.com/userfiles/file/78284828241.pdf
    • http://hoangle.vn/uploads/userfiles/file/87364708236.pdf
    • http://namlongprojects.com/images/uploads/files/vorexofuvu.pdf
    • https://ap-qatar.com/userfiles/files/pumajatoxerolisixim.pdf
    • http://nipissing-lodge.com/clients/b/be/be32fa5c9d1e5a871f1efa0d35b29fe7/File/55358105707.pdf
    • http://agnieszkapawlik.com/userfiles/file/35384169977.pdf
    • http://ipvoicenj.com/wp-content/plugins/formcraft/file-upload/server/content/files/160caddf2605d9---zamalarivi.pdf
    • http://irinaburmistrova.ru/files/7710602700.pdf
    • https://www.alarisusallc.com/wp-content/plugins/super-forms/uploads/php/files/9740cadc24eca0aba4659479110bc03b/64983851775.pdf
    • https://g-ortho.com.br/wp-content/plugins/formcraft/file-upload/server/content/files/160a55de6c020f---69483337514.pdf
    • https://masterjobintl.com/ckfinder/userfiles/files/rexoxiwap.pdf
    • https://uetty.xyz/js/ckfinder/userfiles/files/lefutelekawotikewutaxiri.pdf
    • http://www.loockuniformes.com.br/home/wp-content/plugins/formcraft/file-upload/server/content/files/16102952ac4de6---bevalatiw.pdf
    • https://www.luthier-auxerre.fr/ckfinder/userfiles/files/mepisatotipubavunuxave.pdf
    • https://paloaltospeakerseries.com/wp-content/plugins/super-forms/uploads/php/files/836da197588df2cf10779e86ba5fded7/13753540720.pdf
    • http://mimarkamilozkartal.com/userfiles/files/23754940309.pdf
    • http://cnkls.com/userfiles/file/1624713895.pdf
    • https://feedproxy.google.com/~r/skout/mBVl/~3/3vuEKuznOb8/uplcv?utm_term=linksys+wrt54g+v1+manual
    • 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_off000138ec.bin
9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
pdf-font-stream PDF embedded font (sfnt) at offset 0x138EC 16792 bytes
font_01_sfnt_off00015103.bin
961dafdc34becb3ec75d5eac7d28b208679d8eed07d8847d16bc4cd4a25e86fb
pdf-font-stream PDF embedded font (sfnt) at offset 0x15103 10880 bytes
font_02_sfnt_off00016a42.bin
4d7289707f620436b4928ea347d88673ebc376081dc91b338f797d2f49094d28
pdf-font-stream PDF embedded font (sfnt) at offset 0x16A42 19668 bytes