Malicious PDF — malware analysis report

Static analysis result for SHA-256 f21abbf79c490066…

MALICIOUS

PDF

76.6 KB Created: 2021-06-05 20:50:18 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 4.8.7) First seen: 2021-11-24
MD5: 102053225347ffa4849e2c39611bb6fd SHA-1: 5df411ef942c9af386a016eefce5977255eb8011 SHA-256: f21abbf79c490066e830986768cd1b9d83fca4b42e7dcfc612feabad940e7065
186 Risk Score

Malware Insights

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

This PDF file was flagged as malicious by a ML classifier and ClamAV, indicating a high likelihood of malicious intent. It contains a large number of external links, many of which are hosted on disposable domains, suggesting a link farm or phishing operation. The embedded document body text, though corrupted, mentions 'Free video chat app android', which is likely a lure to direct users to malicious sites.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9997

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://philabc.ru/pbw?utm_term=free+video+chat+app+android PDF link annotation
    • https://pitisugokusibim.weebly.com/uploads/1/3/4/4/134445344/1475346.pdfIn PDF document text
    • https://xojutezakiveze.weebly.com/uploads/1/3/5/3/135318362/7169530.pdfIn PDF document text
    • https://ragibifurox.weebly.com/uploads/1/3/1/3/131379945/tiguve.pdfIn PDF document text
    • https://feposogasutam.weebly.com/uploads/1/3/1/3/131384530/xavazaxaxozubaw.pdfIn PDF document text
    • https://dopapebo.weebly.com/uploads/1/3/4/8/134870178/lerujanumopon.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/6b0f1f9e-ad94-4039-ac05-8615ddfec4a1/13135748098.pdfIn PDF document text
    • http://jesababa.pbworks.com/w/file/fetch/144413961/do_graphic_designers_make_album_covers.pdfIn PDF document text
    • http://xugilip.pbworks.com/w/file/fetch/144558720/70371899023.pdfIn PDF document text
    • https://uploads.strikinglycdn.com/files/feb84321-070a-49f0-bb4a-30dc92b97a98/lojuwukalumonalebakesi.pdfIn PDF document text
    • http://kuzimotum.pbworks.com/f/rozebifoxojo.pdfIn PDF document text
    • http://redejok.pbworks.com/w/file/fetch/144518949/what_is_the_difference_between_acrylic_sheet_and_plexiglass.pdfIn PDF document text
    • http://mulasamesi.pbworks.com/f/how_to_withdraw_nedbank_mobile_money.pdfIn PDF document text
    • https://uploads.strikinglycdn.com/files/9900991c-4261-4bf8-92b9-0d5934bf908c/gijigazawujit.pdfIn PDF document text
    • https://uploads.strikinglycdn.com/files/3e039b01-1f21-4faa-a481-ea8fb64c811d/vocabulary_workshop_level_c_unit_10_synonyms_and_antonyms_quizlet.pdfIn PDF document text
    • https://uploads.strikinglycdn.com/files/370316d3-3dd7-4160-8689-9dbd1e9aecb1/how_to_know_if_a_diode_is_faulty.pdfIn PDF document text
    • https://uploads.strikinglycdn.com/files/97ca186f-45b9-4540-a2d3-e2cb7c9e13a9/how_to_reset_wd_my_cloud_mirror.pdfIn PDF document text
    • https://uploads.strikinglycdn.com/files/159bfe5c-8138-4955-9ce3-35525b4058c7/what_is_polymorphism_in_python.pdfIn PDF document text
    • https://uploads.strikinglycdn.com/files/bfa73c29-0837-40a3-b1bc-a6e3953e88b4/what_are_the_original_game_of_thrones_books.pdfIn PDF document text
    • http://wikoborumun.pbworks.com/f/que_beneficios_tiene_el_magnesio_para_la_salud.pdfIn PDF document text
    • http://mazibudikor.pbworks.com/f/fibaliponamaxugutilazulup.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_off0000f149.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xF149 4964 bytes
SHA-256: bc15f8eeb0f5a1f020da8eb3d6340702e79e6378b40f02482b1c7e2f891b526d
font_01_sfnt_off00010231.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x10231 10336 bytes
SHA-256: 22e9f9759b958bfa75fed1e3f2247995c9bf72e42c575f2b67e1345e527eb784