Malicious PDF — malware analysis report

Static analysis result for SHA-256 90c3c5d69df94675…

MALICIOUS

PDF

97.6 KB Created: 2021-06-07 16:19:02 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 4.8.7) First seen: 2021-11-24
MD5: 8f4b7f82ffc33167b6f3ea66a60a586e SHA-1: a8a35ca7f5b1f0ca078ea7f4f3255a76d60dfa56 SHA-256: 90c3c5d69df94675a3a05fa3d16bc45a7fc8960f1e8566fa13b9dfa75f2ee67d
186 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment T1204.002 Malicious Link

The PDF contains a large number of external links, many hosted on disposable domains, characteristic of SEO spam or phishing lures. The ClamAV detection and ML classifier strongly indicate malicious intent, specifically identified as Pdf.Phishing.Trojan. The document body, though obfuscated, suggests a lure related to 'quantitative analysis for management answer key', aiming to trick users into visiting malicious links.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9995

Heuristics 6

  • ClamAV: Pdf.Phishing.Trojan-d2568dad23a94d95-d2568dad23a94d95-10044375-0 critical CLAMAV_DETECTION
    ClamAV detected this file as malware: Pdf.Phishing.Trojan-d2568dad23a94d95-d2568dad23a94d95-10044375-0
  • Small PDF contains mass external PDF link farm critical PDF_SEO_LINK_FARM
    Small PDF contains many clickable external PDF links, mostly clustered on one host. This matches generated SEO/link-farm PDF carriers used to route users into malicious or unwanted-software delivery chains, rather than a normal document citation pattern.
  • 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://huntic.ru/pbw?utm_term=quantitative+analysis+for+management+answer+key PDF link annotation
    • https://teparapilaw.weebly.com/uploads/1/3/4/4/134477765/mimifupupa-nivimem.pdfIn PDF document text
    • https://lutividagij.weebly.com/uploads/1/3/4/8/134896544/misosadabogixaf.pdfIn PDF document text
    • https://zolumidesejutis.weebly.com/uploads/1/3/5/3/135327041/nimigosukuluko.pdfIn PDF document text
    • https://rufogeror.weebly.com/uploads/1/3/4/6/134664275/faxejoziwa.pdfIn PDF document text
    • https://bafixexewav.weebly.com/uploads/1/3/4/3/134352321/86e8eecc6ffc49.pdfIn PDF document text
    • https://gujejitemisadud.weebly.com/uploads/1/3/4/3/134354005/e17243e401.pdfIn PDF document text
    • https://dojibabebane.weebly.com/uploads/1/3/2/6/132682208/471769449.pdfIn PDF document text
    • https://bisubobotikimix.weebly.com/uploads/1/3/1/4/131438323/5211607.pdfIn PDF document text
    • http://www.ascendercorp.com/In PDF document text
    • http://www.ascendercorp.com/typedesigners.htmlIn PDF document text
    • http://midevodimu.pbworks.com/f/gebenomarivix.pdfIn PDF document text
    • http://mugobug.pbworks.com/w/file/fetch/144751569/17078372072.pdfIn PDF document text
    • http://vugufosenene.pbworks.com/f/97817450678.pdfIn PDF document text
    • http://bekivuxuga.pbworks.com/f/how_can_i_find_a_name_to_a_phone_number_for_free.pdfIn PDF document text
    • http://barumena.pbworks.com/w/file/fetch/144777423/zokerapavumofubowup.pdfIn PDF document text
    • https://uploads.strikinglycdn.com/files/58bd8040-0abd-4cc5-a33d-4d99a63e27c6/97864199111.pdfIn PDF document text
    • https://uploads.strikinglycdn.com/files/90139519-423e-4878-a597-a9e58a8e21d4/blogging_all-in-one_for_dummies_free_download.pdfIn PDF document text
    • http://sikovifif.pbworks.com/f/devejojazo.pdfIn PDF document text
    • http://gatasulupu.pbworks.com/w/file/fetch/144758196/vuxaji.pdfIn PDF document text
    • http://kafunujazuwo.pbworks.com/f/12343895559.pdfIn PDF document text
    • https://uploads.strikinglycdn.com/files/167b8523-addc-4e52-b761-04a3420b1ad5/can_you_fix_diastasis_recti_years_later.pdfIn PDF document text
    • http://kibumezi.pbworks.com/f/ezgo_powerwise_qe_charger_fault_codes.pdfIn PDF document text
    • http://tusoxefum.pbworks.com/f/skyrim_se_female_walking_animation_mod.pdfIn PDF document text
    • http://sijomirurefi.pbworks.com/f/space_shooter_fury_raiden_mod_apk_unlimited_gems.pdfIn PDF document text
    • https://uploads.strikinglycdn.com/files/09c87a4b-73eb-4958-866c-0c0c3217553c/80636435424.pdfIn 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 2

Files carved from inside the sample during analysis.

FilenameKindSourceSize
font_00_sfnt_off00013d8b.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x13D8B 5464 bytes
SHA-256: 96a3e290d194807f542b9b73895925fee65b90cb46df6d9f2b7339607ba9217e
font_01_sfnt_off00015035.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x15035 12092 bytes
SHA-256: 8300c1d2367f64c945e9d2fd9ded694ba79cdb9935bf20e397d8a396943b0b05