Malicious PDF — malware analysis report

Static analysis result for SHA-256 73613b5ff9113eae…

MALICIOUS

PDF

77.1 KB Created: 2021-06-13 16:18:12 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 4.8.7) First seen: 2021-08-20
MD5: 744ce207e542a14dd1dd920cfe0803c9 SHA-1: c97821973ca3c62d13f3b04646f4c9ce601a1bad SHA-256: 73613b5ff9113eaec07c5d777942b28166c0ac2f81856e435e8300c2bb1be3fc
164 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment T1059.007 JavaScript T1203 Exploitation for Client Execution

The PDF contains embedded JavaScript and numerous URLs pointing to compromised websites, suggesting it's designed to exploit vulnerabilities or redirect users to malicious content. The heuristic firings indicate a link farm strategy, likely to host or distribute further malicious payloads, and ClamAV detection confirms its malicious nature. The document body, though heavily obfuscated, hints at a 'resume sheet' lure.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9998

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.
  • 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 https://huntic.ru/uplcv?utm_term=resume+sheet+pdf PDF link annotation
    • http://webdulich.com/js/ckfinder/userfiles/files/88982998401.pdfIn PDF document text
    • https://advance-pack.com/editor_upload/file/90131545715.pdfIn PDF document text
    • http://www.uvhk.com/wp-content/plugins/formcraft/file-upload/server/content/files/1609776d3f3f7a---diwetumeteta.pdfIn PDF document text
    • http://xn--90ad5ackt1d.xn--p1ai/wp-content/plugins/super-forms/uploads/php/files/6f869960a5dd3472ee87995391782f9d/6352570783.pdfIn PDF document text
    • http://ccswcd.com/userfiles/file/76630578321.pdfIn PDF document text
    • http://jjmcp.jp/userfiles/Image/file/45873342756.pdfIn PDF document text
    • http://www.1000ena.com/wp-content/plugins/formcraft/file-upload/server/content/files/160bf2e2d4ef4e---8030760222.pdfIn PDF document text
    • http://brilspa.ro/userfiles/file/%5C/delirokef.pdfIn PDF document text
    • https://gk-termopanel.ru/wp-content/plugins/super-forms/uploads/php/files/354864a1d64812904f595a9f3892bbf7/wenofefadovefoxotawen.pdfIn PDF document text
    • https://morethancleaningservices.com/wp-content/plugins/super-forms/uploads/php/files/7c7284e412457166f3722399473b0eae/70355993938.pdfIn PDF document text
    • http://chocolatycakes.com/wp-content/plugins/formcraft/file-upload/server/content/files/16077c98937e9d---48965306849.pdfIn PDF document text
    • http://www.kevinbrooks.ca/wp-content/plugins/formcraft/file-upload/server/content/files/160a7ad8eed70f---24543651645.pdfIn PDF document text
    • https://penal-garazh.ru/files/67237283259.pdfIn PDF document text
    • http://asesorialuishervas.com/wp-content/plugins/formcraft/file-upload/server/content/files/160c3e113f3602---pavazejimukaruribogemax.pdfIn PDF document text
    • http://dribblebar.pl/userfiles/file/45069098669.pdfIn PDF document text
    • https://bentzendesign.se/wp-content/plugins/formcraft/file-upload/server/content/files/1607bad77702cf---61712502366.pdfIn PDF document text
    • http://www.ascendercorp.com/In PDF document text
    • http://www.ascendercorp.com/typedesigners.htmlIn PDF document text
    • http://www.daltonmaag.com/In PDF document text
    • http://www.w3.org/1999/02/22-rdf-syntax-ns#In PDF document text
    • http://purl.org/dc/elements/1.1/In PDF document text
    • http://ns.adobe.com/pdf/1.3/In PDF document text
    • http://ns.adobe.com/xap/1.0/In PDF document text
    • http://ns.adobe.com/xap/1.0/mm/In PDF document text
    • http://ns.adobe.com/xap/1.0/rights/In PDF document text
    • http://scripts.sil.org/OFLIn PDF document text

Extracted artifacts 3

Files carved from inside the sample during analysis.

FilenameKindSourceSize
font_00_sfnt_off0000e3ef.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xE3EF 4568 bytes
SHA-256: ea9f496de7e9180cb854f6dbb8d2c942d3e244d44962801dc6d11faf66ec96da
font_01_sfnt_off0000f37e.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xF37E 11336 bytes
SHA-256: 5a627a1102a2db0f18cab2c94ec09fceab8608c0852783f2246abe4f473c8e25
font_02_sfnt_off0001197a.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x1197A 4324 bytes
SHA-256: b50a2106bf82917db0cd3cf88f63c5e8cc3298b343ace5cffc591b35df33d24c