Malicious PDF — malware analysis report

Static analysis result for SHA-256 e1c0e6e626489b3a…

MALICIOUS

PDF

81.3 KB Created: 2021-09-19 12:47:29 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3)
MD5: 79f94728e8aabd9c6d84d1b8fa5c3b47 SHA-1: 99a17988fecc07ebab4b15b669aa037d73a57b1e SHA-256: e1c0e6e626489b3a3c0de5eab94a20699408f91f7b7f9d69958ed0887fde6762
204 Risk Score

Malware Insights

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

The sample is a PDF document flagged by ML classifiers and ClamAV as malicious. It contains embedded JavaScript and numerous external URLs, many hosted on compromised or disposable domains, suggesting a phishing or malware distribution attempt. The 'SE_BROWSER_INSTALL_LURE' heuristic indicates the document's content likely prompts the user to install a fake browser update or extension, a common social engineering tactic.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9975

Heuristics 8

  • ClamAV: Pdf.Phishing.Trojan-d2528dad23a95d95-d2528dad23a95d95-10044376-0 critical CLAMAV_DETECTION
    ClamAV detected this file as malware: Pdf.Phishing.Trojan-d2528dad23a95d95-d2528dad23a95d95-10044376-0
  • 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.
  • 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://123dvere.sk/files/file/51264320876.pdf
    • http://strahyi.ru/images/file/lejebivomaxegixogufoxozex.pdf
    • https://senegal4d.com/contents/files/sobetunet.pdf
    • http://sjzhtchem.com/upload/files/tibelamobuv.pdf
    • http://emannsltd.com/userfiles/rudewenumalaw.pdf
    • http://bergfin.se/wp-content/plugins/formcraft/file-upload/server/content/files/16136f4791e719---mijipovapusajufejumok.pdf
    • http://www.nisbd.com/wp-content/plugins/formcraft/file-upload/server/content/files/161362ebd1de34---98325763919.pdf
    • http://balmybnb.com/t/tutorfirm/uploads/ck/files/22387555271.pdf
    • https://mysilo.com/upload/ckfinder/files/tekadoja.pdf
    • https://www.solucionaesp.com/ckfinder/userfiles/files/47509266205.pdf
    • http://pansophers.com/wp-content/plugins/formcraft/file-upload/server/content/files/161431d9db922f---25146101099.pdf
    • http://matsusushionline.com/uploads/files/91071506818.pdf
    • https://www.tifdip.com/wp-content/plugins/formcraft/file-upload/server/content/files/1613818fa8befb---fibijinigejakesabumupaxek.pdf
    • https://perfecthospital.org/ckfinder/userfiles/files/dekexowemiseligu.pdf
    • https://kurtoglumob.com/upload/file/89531771644.pdf
    • http://rubella2.integra-sh.com/userfiles/file/fitowuzidaduludulinapipe.pdf
    • https://navoloki.mebel18.com/uploads/files/55501653494.pdf
    • http://ladyqueen.it/userfiles/files/2762674314.pdf
    • http://ip-golubev.ru/ckfinder/userfiles/files/wisigivofo.pdf
    • https://etest.vn/app/webroot/uploads/files/jawigunukig.pdf
    • https://lashmakerpro.it/wp-content/plugins/super-forms/uploads/php/files/ulfthnc24o8lrueo3a3is60l23/837420644.pdf
    • https://beautifullifeuk.com/wp-content/plugins/super-forms/uploads/php/files/737b2318cc2d2596026c3fcc8185b739/11822855672.pdf
    • http://steclotildehorton.ca/wp-content/plugins/formcraft/file-upload/server/content/files/161406570ed0c1---tenulatofozagebitu.pdf
    • https://tndvn.com/js/ckfinder/userfiles/files/27821509081.pdf
    • http://familiehollander.nl/images/uploadedimages/file/37626184794.pdf
    • https://feedproxy.google.com/~r/1eyvgo/aqOO/~3/cv9VXjIrmdE/uplcv?utm_term=excel+to+pdf+online2
    • 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_off0000dbac.bin
9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
pdf-font-stream PDF embedded font (sfnt) at offset 0xDBAC 16792 bytes
font_01_sfnt_off0000f3c3.bin
86f7550c4908073b379ed368bf4c26041ad1a6cdc1e7744af04479b998c9a2bd
pdf-font-stream PDF embedded font (sfnt) at offset 0xF3C3 10388 bytes
font_02_sfnt_off00010b68.bin
d320b6e1cc08c19dad7fc55091751aae18bb98cb9b744c166a00a4f0ee44de71
pdf-font-stream PDF embedded font (sfnt) at offset 0x10B68 17188 bytes