Malicious PDF — malware analysis report

Static analysis result for SHA-256 cb1a2254a7922355…

MALICIOUS

PDF

76.1 KB Created: 2021-04-06 15:54:47 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 4.8.7) First seen: 2021-09-24
MD5: 886701a52cce78ef8f251c4235a59dc9 SHA-1: 50f559d94be196063a6a879843014d0362731383 SHA-256: cb1a2254a7922355211b933fde76bd7209c82cff99eade3c3d3e18be6f54c87f
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 0.9990

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://vilenefex.ru/award?keyword=libro+adrian+paenza+pdf PDF link annotation
    • https://cdn-cms.f-static.net/uploads/4392659/normal_600cf3dcd780d.pdfIn PDF document text
    • https://bagirarivevi.weebly.com/uploads/1/3/1/3/131384609/112501.pdfIn PDF document text
    • https://cdn-cms.f-static.net/uploads/4366348/normal_604069e16842e.pdfIn PDF document text
    • https://jabiratunibi.weebly.com/uploads/1/3/2/6/132683422/efad7a8.pdfIn PDF document text
    • https://static.s123-cdn-static.com/uploads/4379723/normal_5fe25729d8e01.pdfIn PDF document text
    • https://cdn-cms.f-static.net/uploads/4376379/normal_60146795f148e.pdfIn PDF document text
    • https://static.s123-cdn-static.com/uploads/4383679/normal_5ffa29a2d9313.pdfIn PDF document text
    • https://cdn-cms.f-static.net/uploads/4426823/normal_6033bb71bcfe3.pdfIn PDF document text
    • https://cdn-cms.f-static.net/uploads/4369651/normal_5fe96588a4d1b.pdfIn PDF document text
    • https://cdn-cms.f-static.net/uploads/4422161/normal_5fd6484d58966.pdfIn PDF document text
    • https://boxorefo.weebly.com/uploads/1/3/0/9/130969922/3b9a64460824f.pdfIn PDF document text
    • https://cdn-cms.f-static.net/uploads/4417670/normal_601ae1acabda7.pdfIn PDF document text
    • https://cdn-cms.f-static.net/uploads/4459787/normal_602790798a527.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/7ddb8826-a32f-4060-8fed-8774804bb76e/figijezekiroko.pdfIn PDF document text
    • https://184d393c-d2ff-49e5-bbcb-48626b1dbf88.filesusr.com/ugd/49be48_4a5abf806de94bccb2a27bd5acf386db.pdf?index=trueIn PDF document text
    • https://uploads.strikinglycdn.com/files/eb060e29-7399-48cf-aab9-08126c3b9d14/jojufafobevumilowexugi.pdfIn PDF document text
    • https://994180ce-385f-4272-9833-4a204a825e0f.filesusr.com/ugd/ec0c41_814ea5286ef647b3b3c66a2c0a8cabac.pdf?index=trueIn PDF document text
    • https://uploads.strikinglycdn.com/files/ca59df31-20ac-4c85-9102-1e6412bfca59/vabanusidaw.pdfIn PDF document text
    • https://uploads.strikinglycdn.com/files/63b94bca-e714-44a5-beda-cb638a7c2cbc/family_feud_questions_funniest.pdfIn PDF document text
    • https://5de9ed01-d610-4143-94db-6f998645a8ce.filesusr.com/ugd/1d8bf6_47b63af507614686b5aebeb1fd612616.pdf?index=trueIn PDF document text
    • https://b4140449-9b96-4148-8619-c9b3eed7b48c.filesusr.com/ugd/c33cdb_a66e6bc985e64835880d66fb8a58f2b8.pdf?index=trueIn PDF document text
    • https://uploads.strikinglycdn.com/files/4f2615b8-ab0b-4419-b2f2-3a565e01a0b4/lets_explore_diabetes_with_owls_chapters.pdfIn PDF document text
    • https://cad90261-f038-4e8a-b384-2e0e37e6cb8c.filesusr.com/ugd/4c4e45_6e1b1f7351dd4b43920a0f5e489a3514.pdf?index=trueIn PDF document text
    • https://6bc61794-ec17-45f1-96eb-8bed4cd57308.filesusr.com/ugd/217b8a_8af1d13ddb9647bb819b22e3ef339afa.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_off0000e7ec.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xE7EC 4956 bytes
SHA-256: 387f3602226e4389dba9afac7e10082264feb3dd7719a3e4b1a71ce4e89bbea7
font_01_sfnt_off0000f8e1.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xF8E1 12476 bytes
SHA-256: cc3bd6c5ee8c9553ef47781ba3c7fbf45e26d4b9823be8a88394359e629f6055