Malicious PDF — malware analysis report

Static analysis result for SHA-256 4d1c8f835a82a9e3…

MALICIOUS

PDF

89.6 KB Created: 2021-03-27 16:18:11 +02:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 4.8.7) First seen: 2021-09-25
MD5: 70b4b2fa183336fc696519e2dadec73c SHA-1: 5779bbcd5e1253aeee5dcfeb174b49388aae044c SHA-256: 4d1c8f835a82a9e3b61395ea9986dbc98cfd26de021419ad1cfb6811173dec10
186 Risk Score

Malware Insights

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

This PDF document was flagged as malicious by ClamAV and an ML classifier. The file embeds a large number of external links characteristic of an SEO link farm. Specific URLs and indicators for this sample are listed in the indicators section.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9995

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://gimoguvi.ru/award?keyword=bibliography+meaning+pdf PDF link annotation
    • https://static.s123-cdn-static.com/uploads/4462345/normal_5ff184aa5ed6b.pdfIn PDF document text
    • https://cdn-cms.f-static.net/uploads/4401697/normal_5fdb9012ce30d.pdfIn PDF document text
    • http://pugumatinudozid.iblogger.org/22251948419.pdfIn PDF document text
    • https://cdn-cms.f-static.net/uploads/4427105/normal_604cdedb43b86.pdfIn PDF document text
    • https://cdn-cms.f-static.net/uploads/4448096/normal_603b78f048666.pdfIn PDF document text
    • http://jijufik.22web.org/mr_bechara_full_movie_free.pdfIn PDF document text
    • http://www.ascendercorp.com/In PDF document text
    • http://www.ascendercorp.com/typedesigners.htmlIn PDF document text
    • https://8d2868a3-57b7-484c-81f6-493c1c4f5daa.filesusr.com/ugd/a8ca0f_79f1ceb8a4c046c3b9232771199efb16.pdf?index=trueIn PDF document text
    • https://uploads.strikinglycdn.com/files/7057a718-d345-411a-8833-8f48131079e0/how_to_measure_fume_hood_face_velocity.pdfIn PDF document text
    • https://s3.amazonaws.com/kaxukok/nezenuvafivuvusowanaseg.pdfIn PDF document text
    • https://7c9e9c40-2b96-4f88-8065-b5ff5e495659.filesusr.com/ugd/3bfcae_999c9c8225074bdba2d6bc8a8ce5febf.pdf?index=trueIn PDF document text
    • https://uploads.strikinglycdn.com/files/2483a921-2fff-4b24-8fcc-0182db13c16f/24858755244.pdfIn PDF document text
    • https://288c7b4b-0494-48f6-8ee2-9dd519b96b0a.filesusr.com/ugd/a107db_00b4c131138448468b49fdcea4763015.pdf?index=trueIn PDF document text
    • https://s3.amazonaws.com/toliwudalamem/75537873930.pdfIn PDF document text
    • http://biwipekimati.rf.gd/jevoz.pdfIn PDF document text
    • https://ee67c5b3-b4d3-4257-b425-af55881d3a68.filesusr.com/ugd/c60da7_944fbe0a790d45e8a5118bd597f0d2ee.pdf?index=trueIn PDF document text
    • https://6e229dea-1f83-4be8-8cd3-388eabd4f5e3.filesusr.com/ugd/1cfe37_12a2ec2534fb4b37a919fec54d022a5c.pdf?index=trueIn PDF document text
    • http://nisutenapiri.epizy.com/java_8_64_bit_windows.pdfIn PDF document text
    • https://c06d174a-caca-4ab2-b5a0-4525cd3135d4.filesusr.com/ugd/856cea_048a86fb91154a4384f79fca26435ea1.pdf?index=trueIn PDF document text
    • https://s3.amazonaws.com/dufekifaral/defomunenenalus.pdfIn PDF document text
    • https://b7953657-6b45-4ea9-9d9d-f701e3f26526.filesusr.com/ugd/45996c_2da05a3cc32f459ca155fd7e8fe52ce5.pdf?index=trueIn PDF document text
    • https://f3e0ee59-b309-4736-aefa-1db4f942b0be.filesusr.com/ugd/e87662_b2c1569384b748e5bdae102174bf4a1d.pdf?index=trueIn PDF document text
    • https://2e8e3215-33bf-4fe1-bc67-b38dac560527.filesusr.com/ugd/269bb8_101433ae11684aae9060f6c6ef4378ad.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_off00011947.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x11947 5568 bytes
SHA-256: e18458136d27b27ca6d5d2e3e99042ec373806e6d049e5596e036272a7d83827
font_01_sfnt_off00012c16.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x12C16 12744 bytes
SHA-256: 454ace3142c1a24189a37c3650c047505ff46eafdb9c2069ff1edbfb58a28835