Malicious PDF — malware analysis report

Static analysis result for SHA-256 efea9b5bc40ff704…

MALICIOUS

PDF

85.5 KB Created: 2021-04-03 15:45:30 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 4.8.7) First seen: 2021-07-10
MD5: 289ae8387889a00ad19075c921b6f18f SHA-1: 0b4b4a8b9bd04bdf96e8fc26eeba29dd4a11b9fc SHA-256: efea9b5bc40ff7047acebdc95776a32a13ccd7c224dd927f7d0071edad158af5
186 Risk Score

Malware Insights

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

This PDF file was detected as malicious by ML classifiers and ClamAV, indicating a high likelihood of malicious intent. The file functions as a link farm, containing numerous external URLs, many of which are hosted on disposable domains or are part of an SEO manipulation scheme. The primary URL, 'https://nipisod.ru/strik?utm_term=bookshelf+speakers+for+home+theatre', suggests a potential lure for users interested in home theatre equipment, which is then redirected. No scripts were extracted, but the PDF structure itself is designed to facilitate redirection to external sites.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9998

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
  • 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://nipisod.ru/strik?utm_term=bookshelf+speakers+for+home+theatre PDF link annotation
    • http://pagexanomala.22web.org/new_album_song_2019_malayalam.pdfIn PDF document text
    • https://static.s123-cdn-static.com/uploads/4414173/normal_5ffa06a10f5d3.pdfIn PDF document text
    • https://cdn-cms.f-static.net/uploads/4379610/normal_5fe99be53d9f2.pdfIn PDF document text
    • https://cdn-cms.f-static.net/uploads/4444882/normal_60503be76ee35.pdfIn PDF document text
    • http://dogusiwimukames.iblogger.org/nafinegenawu.pdfIn PDF document text
    • https://cdn-cms.f-static.net/uploads/4367290/normal_605ef48c1be76.pdfIn PDF document text
    • https://cdn-cms.f-static.net/uploads/4369508/normal_5fe6342bb533e.pdfIn PDF document text
    • https://static.s123-cdn-static.com/uploads/4383928/normal_5feec92eb0702.pdfIn PDF document text
    • http://zuvinesewuwiz.iblogger.org/rozegaxop.pdfIn PDF document text
    • https://cdn-cms.f-static.net/uploads/4403429/normal_601c03afb46a7.pdfIn PDF document text
    • https://static.s123-cdn-static.com/uploads/4403960/normal_60093de37e3d4.pdfIn PDF document text
    • http://www.ascendercorp.com/In PDF document text
    • http://www.ascendercorp.com/typedesigners.htmlIn PDF document text
    • https://uploads.strikinglycdn.com/files/bba29f10-676c-4e1c-8c52-3d2b5f62214c/does_china_have_religion_freedom.pdfIn PDF document text
    • https://3cd6846c-369c-4875-9c63-132df726a2dd.filesusr.com/ugd/7ab50f_c2e058efc2c94cdb89de433982d892a0.pdf?index=trueIn PDF document text
    • https://5c2df1de-05ea-4e17-9aa3-38adc7ce3153.filesusr.com/ugd/ddd609_6cf3ff344e9a4c7d9a3176399c7ad368.pdf?index=trueIn PDF document text
    • https://uploads.strikinglycdn.com/files/e18f4eeb-2c0c-450b-8cb2-7f08a87fd5c8/what_are_examples_of_phones_in_phonetics.pdfIn PDF document text
    • http://jimatisejur.rf.gd/mixivi.pdfIn PDF document text
    • https://uploads.strikinglycdn.com/files/b3754f01-2a4f-4494-99fb-b396a3716c42/mafia_2_crack_download_free.pdfIn PDF document text
    • https://22e365c6-0853-42e1-82f8-83473bf9c0bf.filesusr.com/ugd/217d68_57a43766a77647d6b38633db83732222.pdf?index=trueIn PDF document text
    • https://6acf0ca1-aa41-4771-8b91-54baff69ee7f.filesusr.com/ugd/7d1dc9_8bd2dcee132c454cb99f5b5515bad9c0.pdf?index=trueIn PDF document text
    • https://1c514d3f-4aca-4c14-a2cc-94ef866bc6c7.filesusr.com/ugd/860217_cdfdba09f49849fe88f266387ac790ef.pdf?index=trueIn 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_off00010fce.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x10FCE 5252 bytes
SHA-256: 1c282e9cf2350577f483060a25cba05a722bf40b2d8dee5ab1f2de50dfc08921
font_01_sfnt_off00012185.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x12185 11552 bytes
SHA-256: a6837416b80216b30cbf46364c5c617c0834da959830b59f6a96b6d8a9babcb0