Malicious PDF — malware analysis report

Static analysis result for SHA-256 5625ca21ac46aab0…

MALICIOUS

PDF

73.8 KB Created: 2021-03-18 02:50:47 +02:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 4.8.7) First seen: 2021-08-25
MD5: 0e4aa3326517ea6c53d3df722d047212 SHA-1: d5ccb8f21488f1fd0448a6e5e8d0c0ceef67d102 SHA-256: 5625ca21ac46aab0ba610529300c53c6cb517cba06e01a155e16a43e1e45719c
244 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment T1204.002 Malicious Link

The PDF file was detected as malicious by ClamAV and an ML classifier, and contains a critical heuristic firing for linking to known malicious redirector infrastructure. It also exhibits characteristics of a PDF link farm, with numerous embedded URLs pointing to various domains, including one identified as a redirector. The document body, though heavily obfuscated, appears to be a lure related to 'Buzz rack bike carrier instructions'.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9997

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
  • PDF links to known malicious redirector infrastructure critical PDF_MALICIOUS_REDIRECTOR_LINK
    PDF contains a clickable URI to redirector infrastructure used by a known malicious PDF SEO/adware delivery campaign. These documents typically rely on user interaction and redirect chains rather than a PDF parser vulnerability.
  • 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.
  • 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://crophysi.ru/strik?utm_term=buzz+rack+bike+carrier+instructions In PDF document text
    • https://fuketuxe.weebly.com/uploads/1/3/4/4/134495293/4114521.pdfIn PDF document text
    • https://cdn.sqhk.co/raxoxawupej/ajgAV1G/pocket_option_broker.pdfIn PDF document text
    • https://cdn.sqhk.co/ribuwikoli/yXNAPja/mirede.pdfIn PDF document text
    • https://cdn.sqhk.co/vekuperik/jdgp8hf/11463211321.pdfIn PDF document text
    • https://bakofusu.weebly.com/uploads/1/3/2/3/132303024/b9b0d.pdfIn PDF document text
    • http://jibakerutev.mypressonline.com/noxujosonozuzenexub.pdfIn PDF document text
    • https://zekogogebiw.weebly.com/uploads/1/3/1/4/131453397/cef19373de06e.pdfIn PDF document text
    • https://webegerux.weebly.com/uploads/1/3/4/7/134759049/vukitabaxusu.pdfIn PDF document text
    • http://www.ascendercorp.com/In PDF document text
    • http://www.ascendercorp.com/typedesigners.htmlIn PDF document text
    • https://71b34470-2e60-4936-811b-9f14cb47e32b.filesusr.com/ugd/1dbbf0_bf8787c6f0044defab02a29ee06c535e.pdf?index=trueIn PDF document text
    • https://93dbb2ad-f1e8-4c6c-adfd-2ef134399473.filesusr.com/ugd/df4650_149bca32d70f4d4e9eebbb04c24256b9.pdf?index=trueIn PDF document text
    • https://uploads.strikinglycdn.com/files/b531c1b1-92c7-4625-b9e8-b17435392e18/will_cyberpunk_be_better_on_ps5_or_xbox_series_x.pdfIn PDF document text
    • https://1c896d37-30d1-4b4d-9537-98f963aae812.filesusr.com/ugd/865d50_6f1a179fc27143338baf9ca40deaceec.pdf?index=trueIn PDF document text
    • http://baxewape.myartsonline.com/meaning_of_promissory_note.pdfIn PDF document text
    • https://356bbf58-84af-4bff-99a9-d03346e46411.filesusr.com/ugd/b5472a_1e1db8779e6442d696758afd3ad67b53.pdf?index=trueIn PDF document text
    • https://uploads.strikinglycdn.com/files/9e66d122-ba8d-4487-b23a-1ccf1c0ef4e9/xoxulaxuxo.pdfIn PDF document text
    • https://uploads.strikinglycdn.com/files/cf621e44-bff3-491d-a785-6c888a68f2e6/7363241381.pdfIn PDF document text
    • https://s3.amazonaws.com/jiwotarotavuz/animal_crossing_wild_world_guide_book.pdfIn PDF document text
    • https://uploads.strikinglycdn.com/files/db9e2a96-0a06-452a-a119-0e8aa12b93bc/yoga_poses_for_weight_loss_in_a_week.pdfIn PDF document text
    • http://nisetekotixob.myartsonline.com/58156549425.pdfIn PDF document text
    • https://uploads.strikinglycdn.com/files/9c70e8ed-d227-426d-85d7-2c733e93cdb2/personajes_de_luces_de_bohemia_por_escenas.pdfIn PDF document text
    • https://s3.amazonaws.com/kabisebax/xobuperokuwoxipowewa.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_off0000e5a9.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xE5A9 5064 bytes
SHA-256: 6b11ce2856199c9b51f8d2945956669e05466e76aeda6fcb6d999916f02fe83c
font_01_sfnt_off0000f6f6.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xF6F6 10248 bytes
SHA-256: 020b3eda34cb4eac4132033a846695c0a552529bdef557dfd3d60426fa632fad