Malicious PDF — malware analysis report

Static analysis result for SHA-256 a4733f5ef8f00001…

MALICIOUS

PDF

83.7 KB Created: 2021-04-05 21:02:08 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 4.8.7) First seen: 2021-11-25
MD5: 39a25ef0ed5decf0f82c0aa2f160d991 SHA-1: 3e686ccc19e4a9824e1d45b6f92499f50a9dcb81 SHA-256: a4733f5ef8f000014a877a891d3037ad2aaacb713b623c6306d67cf89a402e41
206 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment T1059.007 JavaScript

This PDF file was flagged by multiple heuristics as malicious, including ClamAV and an ML classifier. It contains a large number of external links, indicative of a link farm or SEO manipulation, and one heuristic specifically identified it as a 'callback phishing phone lure'. While no scripts were extracted, the presence of numerous external URLs suggests a potential for hosting malicious content or phishing pages.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9996

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
  • 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.
  • Callback phishing phone lure medium SE_CALLBACK_LURE
    Document asks the user to call a phone number in billing, refund, subscription, fraud, or security context — consistent with callback phishing or tech-support scam patterns. Suppressed for legitimate-issuer (IRS/gov/official-form) documents that carry no urgency or charge/dispute escalation.
  • 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://druttle.ru/award?keyword=toefl+exam+details+pdf PDF link annotation
    • https://cdn.sqhk.co/rasufizo/jiibeie/shark_eating_fish.pdfIn PDF document text
    • https://cdn.sqhk.co/befozaxulot/jhhjhhG/98777387261.pdfIn PDF document text
    • http://cetapp.xyz/factoring_polynomials_practice_problemsi8rzs.pdfIn PDF document text
    • https://cdn.sqhk.co/vazoguzo/iuGhhif/21787984726.pdfIn PDF document text
    • https://cdn.sqhk.co/wofikubid/hiPgfPM/play_store_apk_downloader.pdfIn PDF document text
    • https://cdn.sqhk.co/mewovegid/RSeIljj/goalrilla_soccer_goal_net.pdfIn PDF document text
    • https://cdn-cms.f-static.net/uploads/4406793/normal_6037903395d3a.pdfIn PDF document text
    • https://botuwuroxawezu.weebly.com/uploads/1/3/4/7/134713501/jaraduj.pdfIn PDF document text
    • https://cdn-cms.f-static.net/uploads/4490539/normal_602460c58ff02.pdfIn PDF document text
    • https://cdn-cms.f-static.net/uploads/4375521/normal_5fd5fdf75698e.pdfIn PDF document text
    • https://bopamoverera.weebly.com/uploads/1/3/1/4/131408256/pafebexek_tagebivuxadusud.pdfIn PDF document text
    • https://cdn.sqhk.co/pobijejok/Jrifgfj/call_of_duty_warzone_bunker_code.pdfIn PDF document text
    • http://affilateapp.online/61905858899u5wmo.pdfIn PDF document text
    • https://static.s123-cdn-static.com/uploads/4414687/normal_5fc872b899bdf.pdfIn PDF document text
    • https://cdn.sqhk.co/kojogitu/0ihggjj/vuvudanapolunokutinidebim.pdfIn PDF document text
    • https://static.s123-cdn-static.com/uploads/4477387/normal_5fdde0b02226c.pdfIn PDF document text
    • https://cdn.sqhk.co/tajiwikiter/amihXxY/hockey_goalie_equipment_drying_rack.pdfIn PDF document text
    • https://busedulaxuxelo.weebly.com/uploads/1/3/1/3/131379622/beganupojozasoliwefa.pdfIn PDF document text
    • https://cdn.sqhk.co/pupumukisev/gdsAhgj/miniclip_games_zombie_defense_agency.pdfIn PDF document text
    • http://www.ascendercorp.com/In PDF document text
    • http://www.ascendercorp.com/typedesigners.htmlIn PDF document text
    • http://buzezasafez.epizy.com/55767950943.pdfIn PDF document text
    • http://mutidulofof.epizy.com/bluetooth_5_android.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_off000105ca.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x105CA 5108 bytes
SHA-256: 9d642d64473b521341a1b97f9fbe5d211677ce87c2530845c285be2d42834357
font_01_sfnt_off00011725.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x11725 12040 bytes
SHA-256: b2e7d85a63ca674b00a4fd380f1f52190a2fc30e36ec4662f202c8de226d359d