Malicious PDF — malware analysis report

Static analysis result for SHA-256 83092ce72bb14d98…

MALICIOUS

PDF

75.0 KB Created: 2021-05-23 14:47:56 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 4.8.7) First seen: 2021-09-27
MD5: 7e12aa77f28bc6a569fedcd810890f31 SHA-1: cd1d99209fdd0c34a57ce421a3a3e7c8a0cb6763 SHA-256: 83092ce72bb14d9814e5b8f9f8b77183af1b745d958dfecec39f9766ff1b5efc
186 Risk Score

Malware Insights

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

This PDF file is identified as malicious by ML classifiers and ClamAV, indicating a phishing or trojan threat. It contains a link farm with numerous external PDF links, including a primary lure at 'https://baarspo.ru/strik?utm_term=examen+diagnostico+de+ingles+secundaria+primer+grado'. The document body, though heavily obfuscated, suggests a deceptive lure related to an academic exam. No scripts were extracted, but the presence of multiple external links points to a phishing or malware distribution attempt.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9991

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://baarspo.ru/strik?utm_term=examen+diagnostico+de+ingles+secundaria+primer+grado PDF link annotation
    • https://cdn-cms.f-static.net/uploads/4377908/normal_605d6f63bc6b3.pdfIn PDF document text
    • https://jetapixivokob.weebly.com/uploads/1/3/4/7/134726526/kivadokexo_gopasenabob_takuzusiwa.pdfIn PDF document text
    • https://cdn-cms.f-static.net/uploads/4467005/normal_605f651900142.pdfIn PDF document text
    • https://static.s123-cdn-static.com/uploads/4414494/normal_5fc9291030fac.pdfIn PDF document text
    • https://bewanabexujafo.weebly.com/uploads/1/3/6/0/136050633/5951353.pdfIn PDF document text
    • https://cdn-cms.f-static.net/uploads/4417662/normal_6036ceab84403.pdfIn PDF document text
    • https://sekagerufelijet.weebly.com/uploads/1/3/5/9/135965199/b05ab3.pdfIn PDF document text
    • https://ramakizuwag.weebly.com/uploads/1/3/4/3/134321509/062c8565.pdfIn PDF document text
    • https://cdn-cms.f-static.net/uploads/4393898/normal_6053b69804a67.pdfIn PDF document text
    • https://sesuzefodapu.weebly.com/uploads/1/3/2/8/132815176/9567229.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/4959701a-bc82-4ad2-beb0-a18dd1bbd712/dmgr4_monster_mythology.pdfIn PDF document text
    • https://s3.amazonaws.com/baxunaf/video_er_app_for_computer.pdfIn PDF document text
    • https://uploads.strikinglycdn.com/files/864c5a71-9a2d-42a3-9367-27ab49e075b6/xefuzewuwepanazitipereked.pdfIn PDF document text
    • https://uploads.strikinglycdn.com/files/c1b15c04-b97d-4ba5-b6f3-9ddb53cf34c1/58923375355.pdfIn PDF document text
    • https://uploads.strikinglycdn.com/files/94484501-35c4-4c9e-85d1-554c38997dc5/the_birchbark_house_chapter_12.pdfIn PDF document text
    • https://uploads.strikinglycdn.com/files/8c7f1dfa-f8d2-4041-8de9-c8329e71bdf6/lanebasupibof.pdfIn PDF document text
    • https://s3.amazonaws.com/rekawexuretowo/php_change_date_format_month_name.pdfIn PDF document text
    • https://s3.amazonaws.com/xotomisen/bhagavad_gita_in_sanskrit_with_meaning_in_hindi.pdfIn PDF document text
    • https://uploads.strikinglycdn.com/files/144c5938-2ec6-4d09-98f8-1e45fbaed5c3/feduwalinofux.pdfIn PDF document text
    • https://uploads.strikinglycdn.com/files/4b04ad79-a0a7-4aba-bc1e-eca54f6145be/nutusixazukawixiz.pdfIn PDF document text
    • https://uploads.strikinglycdn.com/files/8267fd0b-e35f-44d2-9d1d-1a64b71d5578/ferusukigakup.pdfIn PDF document text
    • https://s3.amazonaws.com/bulikowexunepov/32965878003.pdfIn PDF document text
    • https://s3.amazonaws.com/daselex/adjectif_franais_arabe.pdfIn PDF document text
    • https://uploads.strikinglycdn.com/files/096e4424-16ee-4ba3-994d-eec6a66de3f3/how_to_clean_drain_pump_in_bosch_washing_machine.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_off0000e2ab.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xE2AB 5420 bytes
SHA-256: 85663158b7e9a97c9d15c574a27f771402005c14b0875cd1959eb82698ac4dc7
font_01_sfnt_off0000f509.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xF509 11988 bytes
SHA-256: 03045c6e89d69f05b9f1505fbb5e9512ce346a54d161f7770a791ec807ae1c90