Malicious PDF — malware analysis report

Static analysis result for SHA-256 9955f6c8f5f5f863…

MALICIOUS

PDF

81.5 KB Created: 2021-07-21 22:26:14 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3)
MD5: 6f00c7c9bff6a7a17239ac6b8a0f54ad SHA-1: 781f070df0c2fc8572bf096950672ad29c38ff2d SHA-256: 9955f6c8f5f5f8631c521fabed4ae3442ab0f1ee8f0893cca7027fbfecacb1c7
156 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment

The file was detected as malicious by ClamAV and an ML classifier, indicating a high likelihood of malicious intent. It contains numerous links pointing to compromised WordPress upload storage and other domains, suggesting a link farm designed to redirect users to malicious content. The presence of external URIs and link farms strongly suggests a phishing or malware distribution attempt.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9974

Heuristics 6

  • ClamAV: Pdf.Phishing.Trojan-d2528dad23a95d95-d2528dad23a95d95-10044376-0 critical CLAMAV_DETECTION
    ClamAV detected this file as malware: Pdf.Phishing.Trojan-d2528dad23a95d95-d2528dad23a95d95-10044376-0
  • 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://esteticarcare.com/wp-content/plugins/super-forms/uploads/php/files/43cf231d35b710936eba37f13d0261a6/43998345496.pdf
    • http://zbraneklapka.cz/ckfinder/userfiles/files/12361038451.pdf
    • http://sarahscupcakery.com/wp-content/plugins/formcraft/file-upload/server/content/files/16078bd6253831---70615344663.pdf
    • https://canvasations.com/wp-content/plugins/super-forms/uploads/php/files/7bdqqkb1k72jjbl50qsk78qb85/nusekogega.pdf
    • https://pankalconstructora.com/wp-content/plugins/formcraft/file-upload/server/content/files/1608d7425a9b1b---lidebuzepaliwed.pdf
    • http://springswellness.net/wp-content/plugins/formcraft/file-upload/server/content/files/1609014a7a63ae---793390934.pdf
    • http://www.gainerwindows.ca/wp-content/plugins/super-forms/uploads/php/files/76junf85iic0kh2j2bn2qamst3/gilikezamulolemikomadap.pdf
    • http://chupanhnoithat.vn/upload/files/zabusuvulid.pdf
    • http://sungsam.net/userData/board/file/vaweborugumozasikewani.pdf
    • https://isabellepieman.com/userfiles/file/pekuvetifojadavuwaxo.pdf
    • https://7gking.tw/upload/files/pasuz.pdf
    • http://royalgroup.at/tmp/tijutuvuxiwijavuzi.pdf
    • https://nutricount.cz/UserFiles/File/85045257936.pdf
    • http://sieckultury.pl/wp-content/plugins/super-forms/uploads/php/files/cdbcda0007e1d927565bb4a87bfc2d54/50702028103.pdf
    • https://www.sacproblemleri.com/wp-content/plugins/formcraft/file-upload/server/content/files/1608c927486a34---63168120700.pdf
    • http://cjatkinson.com/userimages/bizikujapeze.pdf
    • https://alignerco.com/wp-content/plugins/super-forms/uploads/php/files/cef4e0be7fceb51adddb39c8664db609/41991479684.pdf
    • https://sinarwaja.com/account/files/65732588211.pdf
    • http://dolphinegypt.net/userfiles/file/vubimegepivamumenawejin.pdf
    • https://provisionsinternational.com/wp-content/plugins/formcraft/file-upload/server/content/files/1608248ff5a681---navegujabuxijezojulavuvo.pdf
    • https://inclinedigital.com/wp-content/plugins/formcraft/file-upload/server/content/files/160c0b455521a8---kivikiwotanaw.pdf
    • http://bhs-class1957.com/clients/35434/File/57309268833.pdf
    • http://market-oborudovanie.ru/upload/file/89034983339.pdf
    • https://regalcabs.co.uk/wp-content/plugins/formcraft/file-upload/server/content/files/160e93fc27218c---lulimugug.pdf
    • https://feedproxy.google.com/~r/skout/mBVl/~3/ngfLrbzwjls/uplcv?utm_term=moore+middle+school+lawrenceville+ga
    • 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_off0000d9d8.bin
9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
pdf-font-stream PDF embedded font (sfnt) at offset 0xD9D8 16792 bytes
font_01_sfnt_off0000f1ef.bin
581679b4d9f54b408c934c062ac1648cd9b29eba1d92ecd9a6f8ef7ddb027cb8
pdf-font-stream PDF embedded font (sfnt) at offset 0xF1EF 10864 bytes
font_02_sfnt_off00010aad.bin
57c0aa8f4f4700d05458f62bc9e4b531a6928b3cee2810a1ff37cfb1935ff243
pdf-font-stream PDF embedded font (sfnt) at offset 0x10AAD 16728 bytes