Malicious PDF — malware analysis report

Static analysis result for SHA-256 280269b1973955de…

MALICIOUS

PDF

78.6 KB Created: 2021-06-03 17:06:05 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 4.8.7) First seen: 2021-11-25
MD5: 671f7b7cdd34978c6f7f71526cb8774b SHA-1: 08d52ba87b7a5b5be171a51b71d0b3a95ee6ba97 SHA-256: 280269b1973955de1155e4cf114d695bfa27003a164c79f942584440f968d1ac
186 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment

The PDF contains a large number of external links, many pointing to disposable hosting services, indicating a link farm or SEO spam operation. The ClamAV detection and ML classifier strongly suggest malicious intent, likely phishing or malware distribution. The document body, though partially corrupted, contains keywords related to 'Java debugging programs' and the authoring application 'wkhtmltopdf', suggesting a lure to trick users into visiting malicious sites.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9996

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://queure.ru/pbw?utm_term=java+debugging+programs+questions+with+answers+pdf PDF link annotation
    • https://lanekuloriko.weebly.com/uploads/1/3/0/8/130874063/3627138.pdfIn PDF document text
    • https://perelixaji.weebly.com/uploads/1/3/4/8/134881923/80ad80.pdfIn PDF document text
    • https://kesesitevon.weebly.com/uploads/1/3/5/3/135317357/lebarevimenati.pdfIn PDF document text
    • https://mojipolizu.weebly.com/uploads/1/3/4/3/134318612/jefaso.pdfIn PDF document text
    • https://sozakipebi.weebly.com/uploads/1/3/0/8/130814717/7831230.pdfIn PDF document text
    • https://cdn-cms.f-static.net/uploads/4445534/normal_604d2475b4583.pdfIn PDF document text
    • https://jozeturibunoza.weebly.com/uploads/1/3/4/4/134491641/6438941.pdfIn PDF document text
    • https://nusomosuguxapo.weebly.com/uploads/1/3/4/6/134693055/miniwubipozuju.pdfIn PDF document text
    • https://cdn-cms.f-static.net/uploads/4413007/normal_605a100e0f580.pdfIn PDF document text
    • https://static.s123-cdn-static.com/uploads/4457320/normal_600694d5bb4af.pdfIn PDF document text
    • https://sigozebuxofiko.weebly.com/uploads/1/3/4/3/134372047/metopipedegoz.pdfIn PDF document text
    • http://www.ascendercorp.com/In PDF document text
    • http://www.ascendercorp.com/typedesigners.htmlIn PDF document text
    • http://www.daltonmaag.com/In PDF document text
    • https://uploads.strikinglycdn.com/files/80fd56ae-f572-4348-8e84-eec4af8d2dcb/jawobubanuzavapomelikepel.pdfIn PDF document text
    • https://uploads.strikinglycdn.com/files/ebdcbec0-cb96-40bb-910a-133056867f69/a_list_of_transition_words_for_paragraphs.pdfIn PDF document text
    • http://luwapoveduvi.pbworks.com/f/896051576.pdfIn PDF document text
    • http://fepewuwakow.pbworks.com/f/mitazalotepixunikunakemaf.pdfIn PDF document text
    • http://mapaduzipi.pbworks.com/f/how_do_i_connect_my_zebra_printer_to_wifi.pdfIn PDF document text
    • https://uploads.strikinglycdn.com/files/7c49b488-426c-4f2b-8511-99c583e89fdc/how_to_find_income_statement_centrelink.pdfIn PDF document text
    • https://uploads.strikinglycdn.com/files/8092efab-e430-4e55-a2b9-342979b62931/maleeka_madison_character_traits.pdfIn PDF document text
    • https://uploads.strikinglycdn.com/files/384a786e-4f15-494c-b6b2-21a65c7680a2/tool_forge_tinkers.pdfIn PDF document text
    • http://pusavivo.pbworks.com/w/file/fetch/144455568/vagediwoso.pdfIn PDF document text
    • https://uploads.strikinglycdn.com/files/d096e74a-52d1-4b52-8e2a-2ead3b2a20ad/how_many_hurdles_are_in_the_110m_hurdles.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 3

Files carved from inside the sample during analysis.

FilenameKindSourceSize
font_00_sfnt_off0000e7bc.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xE7BC 5712 bytes
SHA-256: c72a12da5aba709341179ea327a0c7f712f2a262b0d86a14e0d2e4bdceffa18c
font_01_sfnt_off0000faf8.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xFAF8 10388 bytes
SHA-256: 3cf18f7d9acb6d6c268bdd75bb84f6eb09a61474db6d89c165b5d6e0ceb25093
font_02_sfnt_off00011e82.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x11E82 4324 bytes
SHA-256: 1158d95dac44631f497756703988ba3645251422e7ff0015d3fca430225e7c3e