Malicious PDF — malware analysis report

Static analysis result for SHA-256 c8bab8f5ec2f7aff…

MALICIOUS

PDF

82.0 KB Created: 2021-03-28 04:00:36 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 4.8.7) First seen: 2021-08-20
MD5: 5453e666698fdf33a4d9fd54d97484d6 SHA-1: cb9583f1330a10077ed6cb582e04f5ea0d861719 SHA-256: c8bab8f5ec2f7affdce78e8f155c74732ee08a8c488c49ea6c5cfbf1faf9ae91
186 Risk Score

Malware Insights

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

This PDF file, identified as malicious by ClamAV and an ML classifier, contains a large number of external links, many of which point to disposable hosting. The document body, though heavily corrupted, suggests a lure related to book templates. The presence of numerous external links indicates an attempt to redirect users to potentially malicious sites, likely for phishing or malware distribution.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9996

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://zajinet.ru/123?utm_term=write+a+book+template+microsoft+word PDF link annotation
    • https://cdn-cms.f-static.net/uploads/4392237/normal_6024549c89b9b.pdfIn PDF document text
    • https://cdn-cms.f-static.net/uploads/4491686/normal_6023ebb952ffa.pdfIn PDF document text
    • https://cdn-cms.f-static.net/uploads/4467043/normal_6013b1658ce07.pdfIn PDF document text
    • https://cdn-cms.f-static.net/uploads/4370987/normal_603726b9ad13c.pdfIn PDF document text
    • https://cdn-cms.f-static.net/uploads/4417824/normal_6029c2d1cc785.pdfIn PDF document text
    • https://cdn-cms.f-static.net/uploads/4489994/normal_6057bbdb72a4c.pdfIn PDF document text
    • https://cdn-cms.f-static.net/uploads/4495550/normal_5fda8d69a38f6.pdfIn PDF document text
    • https://cdn-cms.f-static.net/uploads/4482023/normal_602af48662c15.pdfIn PDF document text
    • https://cdn-cms.f-static.net/uploads/4457302/normal_60556c24ab663.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/d44ecb51-3585-4285-b855-d1b64c39fa30/how_to_calculate_initial_velocity_from_absorbance_and_time.pdfIn PDF document text
    • https://uploads.strikinglycdn.com/files/4c79c9f4-bdad-4cdd-90d6-ff6e9ef43530/how_to_clean_burnt_stove_burners.pdfIn PDF document text
    • https://8f20b4bd-83f7-4a55-8c6f-e9501e2e061c.filesusr.com/ugd/c1c462_0d5c2d7d6dba47c8a8b429729b33d2bc.pdf?index=trueIn PDF document text
    • https://0dea665b-aaaa-42f3-a52c-f86f0fd1efa2.filesusr.com/ugd/8b9728_bef4e94ef3f64d8681da23ad885128dd.pdf?index=trueIn PDF document text
    • https://uploads.strikinglycdn.com/files/94bd55f8-d649-42e7-b9d5-73ebb7c4b5ca/97900731381.pdfIn PDF document text
    • https://de2a8dfc-dc8d-4d62-be3b-f97abdd17bf6.filesusr.com/ugd/c722c2_683a209c015740b1b3f01986552e8215.pdf?index=trueIn PDF document text
    • https://uploads.strikinglycdn.com/files/e0cea596-fdd2-467f-861a-ca858191ff69/what_foods_are_good_for_inflammation_in_the_body.pdfIn PDF document text
    • http://vepitejususas.atwebpages.com/watchmen_hollywood_movie_hindi_dubbed_download.pdfIn PDF document text
    • https://e5baaea7-7007-41de-9367-4ebf3ed55875.filesusr.com/ugd/8e1900_ebdbca117b6540c9addf4c8c6a37c30c.pdf?index=trueIn PDF document text
    • http://mujebik.atwebpages.com/medical_test_report.pdfIn PDF document text
    • https://0d555108-1732-4721-8d72-76d747b2053a.filesusr.com/ugd/1b0481_2119e484ac954ea3b1af134976860f15.pdf?index=trueIn PDF document text
    • http://pusapovewazigu.onlinewebshop.net/zomopewagejikog.pdfIn PDF document text
    • https://uploads.strikinglycdn.com/files/12f25350-c224-4642-bdd0-5f261ecee824/855086092.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_off00010433.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x10433 5612 bytes
SHA-256: 25c350e710ef88c49261e27ee58ff45f8aeef62abfca9f2f16bf7340896a43ed
font_01_sfnt_off00011755.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x11755 10308 bytes
SHA-256: d02481589feb645553b8ac8b0023ddb4a36a57d01df0cc1fc83537b05c8dba2f