Malicious PDF — malware analysis report

Static analysis result for SHA-256 248249973d32b0a5…

MALICIOUS

PDF

81.7 KB Created: 2021-03-17 07:08:26 +02:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 4.8.7) First seen: 2021-08-20
MD5: 2d8fbe331289f5d0dd87810f1e54ae36 SHA-1: c5ad9eb98a99e1572ce3728868d5b8125a38d94e SHA-256: 248249973d32b0a5f9578434890d52f84e1d0dd5a7978fe5a720398846bf3a99
186 Risk Score

Malware Insights

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

The PDF file contains a large number of external links, many hosted on disposable domains, indicative of a link farm or SEO spamming operation. The ClamAV detection and ML classifier strongly suggest malicious intent, likely related to phishing or malware distribution. While no scripts were explicitly extracted, the PDF structure and embedded URIs point towards an attempt to redirect users to potentially harmful content.

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://kuzutuzo.ru/award?keyword=the+creators+boorstin+pdf PDF link annotation
    • https://cdn.sqhk.co/difigobon/dhfieQu/puzobopamepuzukirif.pdfIn PDF document text
    • https://cdn.sqhk.co/kuwafuwawen/jbaygdI/vudekoloweradanosi.pdfIn PDF document text
    • https://zesaxigupube.weebly.com/uploads/1/3/4/0/134016892/d8d31.pdfIn PDF document text
    • https://cdn.sqhk.co/moturalogupe/jeghJxD/nitutakiwikunaxadofukasad.pdfIn PDF document text
    • https://nikizatul.weebly.com/uploads/1/3/5/3/135309179/donujepibem_runuzixegi_nuzexuxetano.pdfIn PDF document text
    • https://bedizegoresupa.weebly.com/uploads/1/3/1/3/131379398/9937339.pdfIn PDF document text
    • https://penopamez.weebly.com/uploads/1/3/4/4/134496097/6aa528a4611e2ea.pdfIn PDF document text
    • https://deluwibenarut.weebly.com/uploads/1/3/1/3/131382693/zotudafufi.pdfIn PDF document text
    • https://fuwurobo.weebly.com/uploads/1/3/0/8/130814642/92560881b42a7.pdfIn PDF document text
    • https://bagukewedofitaf.weebly.com/uploads/1/3/4/5/134507185/kusalixuzi.pdfIn PDF document text
    • http://www.ascendercorp.com/In PDF document text
    • http://www.ascendercorp.com/typedesigners.htmlIn PDF document text
    • https://2a497570-3881-454f-aefc-229a18bbdf22.filesusr.com/ugd/83e24f_79b97a2622494f5bbbe9ea02aeba44f4.pdf?index=trueIn PDF document text
    • https://33edd578-4186-4695-89f3-f56a5a23fc53.filesusr.com/ugd/f17c08_d86c17831dde4ab392869faf66cf7b92.pdf?index=trueIn PDF document text
    • https://cc4f1b1a-08c7-467e-bb5a-e3073ad8caf1.filesusr.com/ugd/ffc175_b9e9108417b14ddf932d0697ee5f0865.pdf?index=trueIn PDF document text
    • https://a1d1c4ac-cf1d-4c58-861c-45d1188f4b60.filesusr.com/ugd/052f3a_9dd75d8435474ffbb3f1e3067e420ea6.pdf?index=trueIn PDF document text
    • https://0491f86b-060d-4f4a-be23-b0d01488777f.filesusr.com/ugd/faa7ef_cf804b1c897446928fbffc4753868b2f.pdf?index=trueIn PDF document text
    • https://fa202315-5cd5-4006-9a99-7c5d4406650e.filesusr.com/ugd/61804c_46a0ff9ec9be4cbf8a5043d2baf4f13d.pdf?index=trueIn PDF document text
    • https://ca7c05ed-d233-4774-9cf9-08ff86aa6c73.filesusr.com/ugd/b42fd6_a1ac7ef464e34de7840235323c9b7d37.pdf?index=trueIn PDF document text
    • https://b6f97e74-198a-461d-a312-d71b9712332b.filesusr.com/ugd/a2d007_7c94e1a8031f4c75a16ded9b8556ae57.pdf?index=trueIn PDF document text
    • https://05282879-aed3-4f16-ac14-d534add4d4bd.filesusr.com/ugd/0f8b7c_70d3f994c3304008bbf2332109f5d5fc.pdf?index=trueIn PDF document text
    • https://edefa294-c65c-46c5-840b-8a4669b9fdfe.filesusr.com/ugd/e4a001_1e61697cbc1042b0ab704cc5f42839bb.pdf?index=trueIn PDF document text
    • https://0cc2a7d0-6f33-4335-9ec9-554d9418487e.filesusr.com/ugd/cb4a18_c61afb280eb6407d803049462ada1bc1.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_off00010304.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x10304 5300 bytes
SHA-256: 4c358fcb946773e1f7f6fdcdffdc156408a995c8bffb32e2ee092fef9e354b14
font_01_sfnt_off000114fa.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x114FA 10752 bytes
SHA-256: 5d363cbaefe08e235003254bcc4a1ae5a93e24a6539b278b8d08c80f1e54bc12