Malicious PDF — malware analysis report

Static analysis result for SHA-256 ff2bdca8b660e46b…

MALICIOUS

PDF

82.6 KB Created: 2021-04-24 19:26:49 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 4.8.7) First seen: 2021-09-24
MD5: 4a261c8eb4c7bb64af25b26572c2ed1a SHA-1: 50d90bafa84cc82c039d9343bee8dacc12c2ba25 SHA-256: ff2bdca8b660e46b0af8b28460a88053b2d7f61c65ba549db39f8e5c9ef1b399
186 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment T1059.007 JavaScript T1203 Exploitation for Client Execution

The PDF file contains heuristics indicating it is part of a credential phishing campaign, specifically impersonating Gmail. It leverages a link farm to redirect users to a malicious URL, which is likely intended to host a further payload or phishing page. The ML classifier strongly supports the malicious nature of this PDF.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9996

Heuristics 6

  • 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.
  • Brand-impersonation credential phishing lure critical SE_BRAND_CREDENTIAL_PHISH
    Document impersonates a well-known consumer brand and uses account-security / verification language ('unusual activity', 'account on hold', 'verify your account') to steer the reader to a credential-harvesting link. Corroborated by: action link to abused redirector https://tekofudarazot.weebly.com/uploads/1/3/1/3/131381521/fumowu_ludelog_kenaso_davaje.pdf.
  • 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://jumiwimov.ru/strik?utm_term=introduction+to+computer+graphics+and+animation+pdf PDF link annotation
    • https://static.s123-cdn-static.com/uploads/4378846/normal_5ffeb4030f26e.pdfIn PDF document text
    • https://cdn-cms.f-static.net/uploads/4390382/normal_60353ddf506e2.pdfIn PDF document text
    • https://cdn.sqhk.co/pufowuvikij/rhisWkQ/18290505947.pdfIn PDF document text
    • https://static.s123-cdn-static.com/uploads/4408598/normal_5ffca50536f88.pdfIn PDF document text
    • https://cdn-cms.f-static.net/uploads/4486778/normal_604ee629ccdf7.pdfIn PDF document text
    • https://cdn-cms.f-static.net/uploads/4446151/normal_6050319551ddb.pdfIn PDF document text
    • https://cdn.sqhk.co/xibetevoxaj/dIAiaGm/1521489255.pdfIn PDF document text
    • https://tekofudarazot.weebly.com/uploads/1/3/1/3/131381521/fumowu_ludelog_kenaso_davaje.pdfIn PDF document text
    • https://cdn-cms.f-static.net/uploads/4485301/normal_603fe4d6d7a9f.pdfIn PDF document text
    • https://cdn-cms.f-static.net/uploads/4414502/normal_6046f825a2697.pdfIn PDF document text
    • https://koruguliduni.weebly.com/uploads/1/3/4/8/134896859/joleraper-fujewajudir-pikerepasu.pdfIn PDF document text
    • https://rabofabi.weebly.com/uploads/1/3/0/8/130813834/27da3.pdfIn PDF document text
    • https://cdn-cms.f-static.net/uploads/4408001/normal_6012a382746b3.pdfIn PDF document text
    • https://cdn-cms.f-static.net/uploads/4459176/normal_603f3e2f5a107.pdfIn PDF document text
    • https://cdn.sqhk.co/pajerelo/FpEhfn0/lerumoluwexomijuzojewisa.pdfIn PDF document text
    • https://cdn-cms.f-static.net/uploads/4501962/normal_6035091202e5c.pdfIn PDF document text
    • https://cdn-cms.f-static.net/uploads/4501028/normal_60610e944ee39.pdfIn PDF document text
    • https://lipopujowojirew.weebly.com/uploads/1/3/1/4/131408954/jiporemoxef-palovesiga-vajovoxigivo.pdfIn PDF document text
    • https://cdn-cms.f-static.net/uploads/4483591/normal_600a658ac0fec.pdfIn PDF document text
    • http://www.ascendercorp.com/In PDF document text
    • http://www.ascendercorp.com/typedesigners.htmlIn PDF document text
    • http://www.daltonmaag.com/In PDF document text
    • https://uploads.strikinglycdn.com/files/b3682c7a-72a9-4cba-8090-0f86335a0838/32093470633.pdfIn PDF document text
    • https://uploads.strikinglycdn.com/files/f775b9d9-48cc-4772-b929-689ce7690e5f/setefamaxakokekela.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 3

Files carved from inside the sample during analysis.

FilenameKindSourceSize
font_00_sfnt_off0000f5dd.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xF5DD 5356 bytes
SHA-256: 8547062d18cfa5fd574e6519eb62e01c18734a70528c3525568ca46664f43c8b
font_01_sfnt_off000107e0.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x107E0 11364 bytes
SHA-256: f42edf5cf638318eff0f18959c2b3804ae97c67f8268cea863a44d72c5eacd94
font_02_sfnt_off00012ea3.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x12EA3 4324 bytes
SHA-256: d1f4a20f0e35a0564be54678b929bb8c711862c507f070c2b9a6abea8daf4378